ALLEGHENY COMMONS

East Common Pilot Project EVALUATION REPORT

Prepared for:

Allegheny Commons Initiative

A project of the Northside Leadership Conference

June 2008

ACKNOWLEDGEMENTS Contributions of the following groups and individuals were vital to the success of the East Common Pilot Project Evaluation. They are commended for their interest in the project, their perseverance, and the input they provided throughout the project process. NORTHSIDE LEADERSHIP CONFERENCE (NSLC) COMMUNITY DESIGN CENTER OF PITTSBURGH (CDCP) ALLEGHENY COMMONS COMMITTEE Marilyn Detwiler - Central Northside Neighborhood Council (CNNC) John Canning - CNNC Tom Barbush - Allegheny West Civic Council (AWCC) Martha Helmreich - AWCC John Francona - Mexican War Streets Society (MWSS) Jeff King - MWSS Lynn Glorieux - East Allegheny Community Council Chris Seifert - Children's Museum of Pittsburgh Derris Jeffcoat - Allegheny General Hospital Dravid Grinnell - Allegheny City Society Pat Rooney - Northside Resident at-large Pat Mangus - Aviary EVALUATION PROJECT SUBCOMMITTEE Andrea Lavin - Design Fund Program Manager, CDCP Alida Baker - Allegheny Commons Initiative, a project of the NSLC Katie Molnar - Historic Review Commission of Pittsburgh David Jahn - City Forester, City of Pittsburgh Mike Gable - Deputy Director of Public Works, City of Pittsburgh Marilyn Detwiler - Central Northside Neighborhood Council John Francona - Mexican War Streets Society Lynn Glorieux - East Allegheny Community Council Christina Schmidlapp - Allegheny Commons Initiative, a project of the NSLC Chris Seifert - Children's Museum of Pittsburgh Jeff King – Mexican War Streets Society This project was funded by a grant from the Community Design Center of Pittsburgh.

TABLE OF CONTENTS INTRODUCTION....................................................................................................................1 ANALYSIS ...............................................................................................................................1 Summary of Data Collection Methods ............................................................................................................1 RECOMMENDATIONS.........................................................................................................2 Historical Accuracy vs. Practicality ................................................................................................................2 Recommendation Format ................................................................................................................................3

Central Walkway ......................................................................................................................................3 Stone Dust Areas ......................................................................................................................................6 Sidewalks Along Streets............................................................................................................................8 Pipe Rail Barrier ....................................................................................................................................10 Benches ..................................................................................................................................................12 Trash Receptacles ..................................................................................................................................14 Light Fixtures .........................................................................................................................................15 Drinking Fountains ................................................................................................................................16 Trees .......................................................................................................................................................17 Flower / Shrub Plantings / Fence / Monument Lighting .......................................................................19 Turf Areas...............................................................................................................................................20 Signs .......................................................................................................................................................21 Street Crossing .......................................................................................................................................22 Stormwater Drainage .............................................................................................................................23 Bidding ...................................................................................................................................................24 Maintenance ...........................................................................................................................................24 Design and Construction Process ..........................................................................................................25

APPENDICES Appendix A: Key Person Interviews Appendix B: Project Meeting Notes Appendix C: City of Pittsburgh Tree Planting Standards Appendix D: Soil Test Results

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INTRODUCTION In 2002, the Allegheny Commons Initiative (AIC), a project of the Northside Leadership Conference, (NSLC) retained Pressley Associates, Inc. to prepare a Master Plan for Allegheny Commons Park. This report studied the historic elements within the park and made recommendations to restore historical accuracy in the park through future improvements. The first project that included such improvements was the East Common Pilot Project. Pashek Associates was retained to develop design and construction drawings for this project. The pilot project was completed in phases, with the bulk of the work built in 2005. Benches and perimeter railing were added in 2007. The idea behind the Pilot Project was to demonstrate design ideas in a small area of the park (between the Hampton Battery Memorial and East Ohio Street) before using them on a much larger scale throughout the park property. In 2007, the AIC applied for and received a grant from the Community Design Center of Pittsburgh to complete an evaluation of the design elements and project process for the Pilot Project. The AIC subsequently retained Pashek Associates to evaluate the Pilot Project and, based on that evaluation, make general recommendations for future improvement projects in all parts of Allegheny Commons. ANALYSIS Summary of Data Collection Methods To thoroughly analyze the various aspects of the Pilot Project, several methods of data collection were used. These methods are described briefly below:

Key Person Interviews First, Pashek Associates interviewed key stakeholders about the park. The project subcommittee compiled a preliminary list of interviewees. This list was augmented by email interviews performed by Allegheny Commons Initiative (ACI) during the Evaluation. A list of key person interviewees is shown below. Eric Van - Parks & Recreation Supervisor, City of Pittsburgh (C.O.P.) Dept. of Public Works (organizes weekly seasonal farmers market in Northeast Common) Mike Gable - Deputy Director, C.O.P. Dept. of Public Works John Samosky - Park Foreman, C.O.P. Dept of Public Works (worked on Pilot Project, involved in Maintenance of the park) David Jahn - City Forester, C.O.P. Dept. of Public Works George Pegher - Consulting Arborist (consulted during Pilot Project) Tony Pampena - President, Tony Pampena Construction (general contractor for Pilot Project) Marion Pressley - President, Pressley Associates, Inc. (Landscape Architecture firm that completed the 2002 Allegheny Commons Master Plan) Christina Schmidlapp - Project Manager, Allegheny Commons Initiative Lisa Ceoffe - Arborist

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Matthew Erb - Arborist, Friends of the Pittsburgh Urban Forest Joe Santangelo - President, Santangelo & Lindsay (Electrical Engineering Firm that worked on the Pilot Project)

Committee Meetings

A planning committee was formed to work with the consultant and be a liaison to the full board of the Allegheny Commons Initiative. They met four times to identify key issues, possible solutions, and review recommendations. Concurrently, Alida Baker met with all of the neighborhood organizations surrounding the park to further identify important issues. Pashek Associates reviewed comments from the public meetings.

Direct Observation

In addition to speaking with stakeholders and others about the results of the Pilot Project, Pashek Associates visited the Pilot Project site several times to see first-hand some of the issues discussed in other forms of input. Pashek Associates Professional assessment of the design elements and process used during the pilot project are included in the recommendations for each element.

Master Plan Review In addition to the methods noted above, Pashek Associates reviewed the Allegheny Commons Master Plan as needed. Master Plan recommendations provided another opinion on some of the issues discussed via other methods.

RECOMMENDATIONS The following recommendations represent the professional opinions of Pashek Associates. These opinions have been informed through a collection of data and opinions from various groups and individuals interested in the Pilot Project. Pashek Associates realizes that forming a consensus on all issues is challenging. The goal of the recommendations outlined in this report is to give the committees insight and recommendations for future projects on the Commons. Historical Accuracy vs. Practicality During the analysis of the Pilot Project, a very distinct pattern emerged among the various responses. Many opinions either took the side of historical accuracy or of practicality. In some cases, design elements in the Pilot Project were both historically accurate and very practical from a maintenance standpoint. However, in most instances, a practical design element (i.e. mulch rings around a tree, the pipe rail barrier paint finish, etc.) brings with it a more modern aesthetic. Further, historically-accurate design often poses maintenance or other problems (i.e. mowers hitting trees without mulch rings, disease wiping out a single-species tree allee). Although historic accuracy was always the goal, at times, a compromise between historic accuracy and modern practicalities was required. It is essential to blend a degree of historical accuracy with modern knowledge that may slightly alter appearance but prevent new-found problems that may not have been present historically (i.e. tree / plant diseases, planning for ease of mowing with a riding mower, etc.)

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Recommendation Format The recommendations set forth in this section of the report address issues that were repeatedly mentioned during discussions of the park. Recommendations are organized according to specific design element (like the “central walkway”). Within the topic areas is the following outline.

Professional Assessment - Pashek Associates gives its opinion on the condition of each design element involved with the Pilot Project as that design elements exists today. If a problem exists, it is identified in this component.

Possible Options - This component contains one or more alternative materials, design ideas, or installation methods that could be used to remedy issues explained in the professional assessment.

Recommendations – Strategies that will lead to meeting the goals of the project mentioned in the first two components are explained here. (i.e. suggestions for future installations or testing).

Cost Analysis - Unit costs, when applicable, are given for each possible solution to an issue with a specific design element (i.e. estimated asphalt paving unit cost: $35 / square yard, concrete $80/ square yard). Each unit costs includes both labor and materials costs, and assume that 1) Pennsylvania prevailing wage rates used, and that 2) all costs will be paid directly (using no in-kind service, etc.)

CENTRAL WALKWAY

Professional Assessment: The desired "exposed aggregate" bituminous paving appearance for the central pathway was not achieved in the Pilot Project. The materials rolled into the asphalt contained too many fines (small particles of dust / sand). These fines prevented the limestone chips from being sufficiently pressed into the hot rolled asphalt. In addition, the asphalt setting bed must be kept at a consistent temperature in order to achieve optimum conditions for setting the limestone. Keeping such a consistent temperature

is a difficult task. These installation challenges resulted in a less than satisfactory surface. There was much discussion about the path width. We believe the width of the central path (15 feet) is close to historically correct, and suits the amount of use it receives. Another issue with the central path is its distance from adjacent mature trees. The central pathway in the Pilot Project area was installed very close to one large ginkgo tree. Several large roots were severed in order to place the path near the tree, which endangered the health of the tree.

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Possible Options: Alternative surface materials include the following: Asphalt with pea gravel included in the asphalt mix (rather than limestone). This method was used in some of the paths in the West Common and with age it achieved the desired rough appearance (see photo at upper right). Plain asphalt would provide a visual contrast between the path and limestone dust, making the path and limestone seem narrower. Porous asphalt could also be explored, but freeze / thaw processes common in our climate may expedite deterioration in porous asphalt. Decorative Bricks / Unit Pavers are aesthetically pleasing, but were never found in the park in the past and are cost prohibitive considering the length of the central path (example photo at middle right) Exposed-aggregate Concrete is ideal aesthetically and appears to have existed in the park historically, but is also far more expensive than most asphalt materials (example photo at lower right). Using other decorative stone rolled into asphalt as seen in Boston and other areas was also mentioned as an alternative. We believe acquiring this stone will be much more expensive than local limestone and sandstone (pea gravel) and rolling the stone into asphalt will be unfamiliar to local contractors, unnecessarily repeating a mistake made on the Pilot Project.

Recommendations:

Our recommendation is that the central path in future phases of the park be constructed using asphalt containing pea gravel. This will be an inexpensive way to achieve the "weathered" look desired for the central path. In addition, the materials are readily available and the installation method will be familiar to many local contractors. A heavy-duty asphalt path is recommended to

Construct central path using asphalt surfaced with pea gravel. Maintain a bituminous paved aisle of 15 feet wide.

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withstand the occasional maintenance vehicle traffic or vehicular use for the weekly farmer's market. It is also important that any material being used for the central walkway be tested first at an off-site location (i.e. a City of Pittsburgh public works materials storage yard, or possibly on a contractor's property) to ensure proper appearance and contractor familiarity with materials and installation method. Corners between the central path and side paths should be rounded per Master Plan recommendations, not sharp, as are the existing pathway corners shown in the following photo. Where the edge of the proposed central walkway passes within 6 feet of an existing mature tree, the path should narrow to allow for a 6' unpaved space around the tree trunk. No roots within this unpaved space should be disturbed. Corners created by this narrowing of the central path should be rounded to create a smooth flowing edge (see diagram below).

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Cost Analysis:

Asphalt mix with pea gravel ...................................................$42 / square yard (sy) Plain Asphalt.................................................................................................$35 / sy Porous Asphalt ..............................................................................................$40 / sy Decorative Bricks / Unit Pavers (requiring underlying concrete base to support vehicles) .........................................................$180 / sy Exposed Aggregate Concrete (4" thick) .....................................................$100 / sy

STONE DUST AREAS

Professional Assessment: In general, we feel that the stone dust areas themselves are a success. In addition, they are recommended at a width of 10 to 15 feet wide, depending on the location of existing trees along the path (as installed) in the 2002 Allegheny Commons Master Plan (p.84). The stone dust areas significantly reduce the need for maintenance when compared to lawn, which grew poorly / sparsely beneath the trees in the central allee. The stone dust is aesthetically pleasing, and its "migration" during rainstorms will only be an issue on the pilot project site, which contains the most slope of any area in the park. Routine maintenance such as raking, sweeping, and spraying weed-killer will resolve minor issues such as stone dust being washed onto the paved central path or being kicked out from under benches.

The edge between the stone dust areas and lawn is a concern, from both aesthetic and maintenance standpoints. The 2002 Master Plan recommends that an edge treatment be used, but no specific solutions are specified. The increased soil alkalinity caused by installation of the stone dust has not had any significant visible effects on the central allee trees to date. Soil tests completed during the Evaluation Project revealed:

Every several years, additional comparative soil tests should be conducted.

Stone Dust Lawn Soil pH 7.1 7.3

Phosphorus 72 ppm 42 ppm Potassium 244 ppm 137 ppm

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Possible Options: Larger Stone - In terms of material, one solution may be to use a slightly larger limestone aggregate - 1/2" to 3/4" in diameter (AASHTO size 1A). Because limestone is an angular, larger pieces may not wash away during rainstorms. Using river gravel is another option. It may provide a different color to the park, but would not be as stable as limestone. Using other decorative stone dust would significantly increase construction costs. Polymer Stabilizer - Another possibility is to add a polymer stabilizer to the existing stone dust. This application will create the feel of a more stable pavement while keeping the appearance of the stone dust. Stone dust particles will still wear away from the surface, but with a much lesser frequency than loose aggregate (such as the existing stone dust).

One polymer stabilizer for aggregate is manufactured by Natural Sand Company in Slippery Rock, PA (see www.naturalsand.com). Their product, simply named Stabilizer, is a natural binder that locks aggregate screenings together, forming a firm, yet porous, natural-looking surface that withstands all types of weather. The photo at left is offered on the Natural Sand Company website. It shows a stabilized aggregate pathway in Coraopolis, PA. Edger - Aluminum and stone edgers were discussed as possible solutions, but any type of small edger between the stone dust and lawn would be a maintenance problem. Mowers may not be able to cut close to the edgers, and the edgers would heave each winter.

These conclusions are supported by comments made during a discussion with Ms. Marion Pressley of Pressley Associates. In that discussion, the idea of Belgian block edging was mentioned, but dismissed due to expense, maintenance issues, historical inaccuracy, and heaving during frosts.

Similarly, Ms. Pressley dismissed timber or steel edging. It would prevent grass from spreading into the stone dust areas, but would also heave during frost, causing a tripping hazard, and be a considerable expense to install. The best option for this edge is to treat it as a plant bed edge. This type of edge (see diagram at left) is constructed by cutting a shallow "trench" with a spade shovel or edging machine. Once created, this trench would prevent stone dust from washing into the lawn areas and would prevent grass from advancing into the stone dust areas.

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Originally Specified Stone Dust – This is, in our opinion, the most cost effective solution. The width will be determined by the location of existing trees along the central walkway. Our goal is straight edge between dust and lawn, while incorporating the tree trunk entirely within the dust band.

Recommendations:

It is important that the color of the stone dust contrast with the asphalt paving surface. We suggest in future phases that test panels be required of the successful contractor. Volunteer labor would be most helpful to complete and maintain the stone dust / lawn edge, sweep stone dust off the paved central path, and rake stone dust back into depressions created in front of benches. These are easy yet time-consuming tasks that, when done by volunteers from the surrounding neighborhood, would help to create a community sense of ownership in the park.

Cost Analysis: Existing stone dust ................................................................$40 / square yard (s.y.) Larger Limestone chips roughly 1/2" to 3/4" in diameter (size 2A)..............................................................................$40 / s.y. River Gravel................................................................................................$47 / s.y. Decorative stone (granite, etc.) ...................................................................$47 / s.y. Shovel-cut Edge ....................................................................$0.25 / linear foot (l.f.) Belgian Block Edgers ..................................................................................$40 / l.f. Aluminum Edger............................................................................................$8 / l.f. Aggregate with All-Natural Polymer..........................................................$50 / s.y.

SIDEWALKS ALONG STREETS

Professional Assessment: The newly-installed concrete sidewalk along East Ohio Street replaced an unnecessarily-wide and deteriorated concrete sidewalk in that location. The new sidewalk is of sufficient width for the pedestrian traffic that walks along this street. Two poles are located in the center of the new sidewalk, forcing pedestrians to walk

around them. This does not seem to cause any problems or hinder pedestrian movement.

Use the originally specified stone dust surface.

Provide “shovel-out edge between lawn areas and stone dust surfacing.

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The wider section of newly-installed sidewalk adjacent to the central path emphasizes points of entrance into the park.

Possible Options: (Cedar Avenue Sidewalk) The sidewalk along Cedar Avenue is too narrow for more than one person to pass where parking meters exist. The solution would be to widen the sidewalk.

However, widening the sidewalks along Cedar Avenue may necessitate removal of soil in some portions of the park, large roots and subsequently compromise the health of adjacent shade trees. The other option would be to leave the sidewalk at its current width. (Northern side of East Ohio Street Sidewalk) One option would be to leave the sidewalk as is. The other option would be to widen the sidewalk to mirror the newly-installed sidewalk on the opposite side of the street.

Recommendations:

Given the addition of the central pathway parallel to the Cedar Avenue sidewalk and the potential tree damage with widening the sidewalk, we recommend not enlarging the width of the Cedar Avenue sidewalk. The poles on the northern side of East Ohio Street adjacent to the park are very near the curb and will not pose any obstacle to pedestrian traffic. The proposed sidewalk there should mirror the newly-installed sidewalk on the south side of the street.

Cost Analysis: Concrete Sidewalk .............................................................$ 65 / square yard (s.y.)

Cedar Avenue sidewalk: Retain existing sidewalk width. Northern side of East Ohio Street sidewalk: Mirror the width of the sidewalk on the opposing side in the Pilot Project.

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PIPE RAIL BARRIER

Professional Assessment: The pipe rail barrier serves its purpose in directing most pedestrian traffic to the park's pathways, creating a semi-formal feel to the lawn areas of the park. The height of the barrier is excellent, providing a sufficient psychological barrier to the lawn at non-entrance areas to the park (see photo at left). The pipe rail barrier also provides an informal seat when the bus shelter on East Ohio Street is full. The glossy finish (shown on next page) on the pipe rail barrier is not historically accurate but is aesthetically pleasing.

The mulch installed beneath the railing is a cost-efficient way to eliminate maintenance. Replacing the mulch several times will still be less expensive than installing any type of paving material. In some cases, a maintenance problem is caused by shade trees whose trunks are within 6 or 7 feet of the pipe rail barrier. Riding lawnmowers used by C.O.P. maintenance crews cannot fit between such trees and the barrier.

Possible Options:

(Rail) There are three possible options: 1) no rail; 2) rail at access points into the park only to reduce cost; or, 3) continuous rail. (Surface below rail) One option would be to place paving material below the railing. A much more cost effective option would be to place mulch below the railing. The last option would be to have grass below the railing which would cause increased maintenance. (Surface between rail and nearby trees) Currently, turf areas between the trees and rail are too narrow to be mowed. There are two options; 1) leave the grass areas between the trees and rail, or 2) fill in those areas with mulch to alleviate the problem of moving between them.

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Recommendations To lessen costs for improvements to future sections of the park and to limit the restrictive feel of the barrier, sections of the barrier should be installed near main entrances only. A section of barrier 150-200 feet in length on each side of each main entrance (where the central walkway crosses a street, and at corners of the park abutting an intersection) would channel pedestrian traffic toward formal entrances. In addition, the strong linear visual created by the barrier would still be effective. If the barrier is desired around the entire perimeter of the park in the future, the "gaps" between previously installed sections could be filled in.

The use of mulch beneath the barrier is a design element that should be repeated in all future installations of the pipe rail barrier in all other parts of the park.

The mulched rings around tree trunks within 6 or 7 feet of the pipe rail barrier should be extended to meet the mulch beneath the barrier (see diagram and below). This would eliminate the need to mow between the trees and pipe rail barrier.

Rail: Install rail at access points into the park. Surface below Rail: Place mulch below the rail. Surface between rail and nearby trees: Place mulch between trees and rail.

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Cost Analysis: Double-shredded bark mulch (4" depth) base................................$0.60/square foot Concrete base (4" thickness)..........................................................$9.00/square foot Pipe rail barrier ..................................................................................$68/linear foot

BENCHES

Professional Assessment: The benches installed as part of the Pilot Project are aesthetically pleasing and somewhat accurately replicate the historic park benches. The use of the center rail is ideal for preventing anyone from lying down and sleeping on the bench. The finish on the bench's timber components has weathered since installation, but that is to be expected with use. The finish is satisfactory (see photo at right).

Frequency of benches and distance between benches and the central path are important. The layout of the benches (in groups of 4 - see photo at left) in the pilot project has created some uncomfortable situations on the central path when a large group congregates at a bench cluster, blocking or creating an uncomfortable environment to get through. In addition, the benches are located approximately 2 feet from the paved central path. The amount of space between the benches and paved walkway allows sitters to swing their legs and displace the stone dust beneath the benches, creating pits in front

of the benches. These pits hold water during and after storms.

Possible Options: (Frequency of benches) One idea discussed was lining the central pathway with benches, similar to the paths in New York City's Central Park (see A). This approach is suitable for short lengths of the path such as that in the Pilot Project area, but may be cost

A.

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prohibitive for the entire park given the length of the path. Additional groups of 4 benches should be installed between the existing groups in the Pilot Project area to provide more seating options for those using the park.

Future improvements to other longer stretches of the path (i.e. Northeast Common) should include installing benches in groups of 4, all one side of the path (see B). These groups should alternate between each side of the path and should be staggered. These larger groups of benches will provide many seating options while hopefully preventing uncomfortable situations involving groups blocking the central path.

It should be noted that more programmed community activities in the park will fill the park with people, making loitering by people waiting for nearby shelter services or illegal activity less likely. (Distance of benches off pathway) The existing bench location, in terms of distance from the central path to the front of the bench, is causing pits to form in front of benches when sitters displace stone dust by swing or move their feet. Although this is a minor problem, it can be avoided by placing the bench immediately adjacent to the path edge. The alternative solution is to provide a concrete pad under the bench.

The proposed bench location nearer to the central path is more historically accurate, considering some of the historic photos included in the master plan (see photo at left) that show benches resting on the paved central pathway.

Recommendations:

B.

Frequency of benches: Benches should be staggered, on alternate sides of the central path, in groups of 4. Distance of benches off pathway: Move benches closer to central pathway.

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The benches already installed in the pilot project should move toward the central path so that sitters' feet rest on the edge of the paved central walkway. The front edge of the bench supports / legs should be no more than 6 inches away from the edge of the asphalt path. All benches installed in future phases should also be placed closer to the central pathway. This will avoid extra maintenance, eliminate the need for pavement of any kind beneath benches, and will still allow use of the full width of the central pathway for maintenance vehicles and trucks used during the seasonal weekly farmers' market. Dedication plaques on all benches should be placed in the center of the bench, right above the central armrest. This plaque location (as seen on a bench in the Pilot Project) works well because sitters do not have their backs against the plaque.

Cost Analysis: Individual bench cost (with concrete footings only)..........................$1,350 / bench Additional concrete slab (4" thick) beneath an entire bench .........add $125 / bench

TRASH RECEPTACLES

Professional Assessment: The appearance of the trash receptacles seems to be satisfactory. Two issues raised during the evaluations were: 1) the size of the trash receptacles, and 2) the need for lids to prevent the placement of full bags of garbage in the receptacles and prevent water from entering the

receptacles in the winter and freezing. The size of the trash receptacles in the park (see far left) is sufficient for park use. The larger receptacles, such as those along East Ohio Street (see near left) to the east of the park, are not necessary. Possible Options: There are two options, leave the trash receptacles as is, or install lids on them.

Recommendations: One or two of the trash receptacles installed as part of the Pilot Project could receive lids as a test of appearance and utility before lids are applied to all trash receptacles.

Provide trash receptacles with lids.

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Cost Analysis: Trash Receptacle (size currently used in the park) ................................. $835 / each

LIGHT FIXTURES

Professional Assessment: The appearance of the light fixtures is historically accurate and very pleasing. The main issue to be addressed is weather or not the glare of the bulbs is a problem. No complaints have been voiced by residents living adjacent to the Pilot Project area, and an increase in positive night-

time park users has been observed. This could be due to the brighter lights in the park adding to visibility from surrounding streets. However, some park users have expressed concern that the light fixtures are too bright at eye level.

It should be noted that comments reviewed as a part of this study were made during winter months, when central allee trees in the park were not in leaf. Fully-leaved trees in the summer may significantly filter the light from the lamp posts that falls on adjacent properties. The floodlights installed at the Hampton Battery Memorial (see left) were ripped out of the ground by hand. Clearly, the lights need to be anchored with a concrete footing. C.O.P. Public Works crews plan to install stronger anchors or possibly concrete footings to prevent such vandalism again. Sand bags have been placed around each floodlight

as a temporary way to secure the floodlights.

Possible Options:

(Lighting fixtures) Possible solutions would be to install either a coated lamp, a type V Bonsilicate glass refractor or a frosted chimney. All of these will reduce glare. The lighting manufacturer has donated samples to be installed on several existing lights in the Pilot Project for the committee to compare glare.

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(Floodlights) The only option to fixing the problem with the floodlights would be to anchor them, preferably, with concrete footings.

Recommendations:

Cost Analysis: Light fixture modifications – to be determined one option is selected Floodlight anchors ................................................................. $200 / lighting fixture

DRINKING FOUNTAINS

Professional Assessment: The historical drinking fountain installed as part of the Pilot Project is a beautiful piece of functional sculpture and is well-suited for use as a demonstration piece. A number of granite bases exist throughout the remainder of the park that can be used for new fountain locations in future improvement phases. The only issue regarding these fountains is their lack of handicapped access.

Possible Options: Two possible simple solutions would each provide the needed handicapped access. In addition to the fountains that should be installed at historic locations in future phases, handicapped accessible drinking fountains should be installed. Thus, not every drinking fountain in the park would be handicapped accessible, but many would. The two options for handicapped fountains are: 1) a traditional-looking fountain ordered from a catalog (pictured at lower left); or 2) a custom design for a handicapped accessible fountain mimicking the appearance of the existing fountain installed as part of the Pilot Project.

Lighting fixtures: Review tests of lighting fixture options on existing lights.

Floodlights: Anchor floodlights to concrete footings.

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Because the Pilot Project area is relatively small compared to the remainder of the park, no additional drinking fountains should be installed in that area.

Recommendations:

Cost Analysis: Catalog-ordered traditional drinking fountain ..................................... $4,750 / each Custom handicapped-accessible drinking fountain design* ................ $7,000 / each (* includes cost of custom design / fabrication)

TREES

Professional Assessment: Two major issues have arisen concerning the installation of new trees. First is that trees installed as part of the Pilot Project were planted too deep (see upper right). If a tree is planted too shallow, the exposed roots will grow bark and can endure air exposure. However, a tree's trunk cannot withstand being covered with soil and may rot, causing the tree to die. The second concern is that the mulch rings around the trees in the park (pictures on previous page and at right) are too thick, and thus give the park a suburban feel.

Possible Options: (Tree plantings) none (Mulch Trees) This issue is an example of historical accuracy vs. practicality. Trees in the park historically were not planted with mulch rings. However, mulch rings are beneficial to trees, and help prevent tree damage by riding mowers (which did not exist when the park was built). There are three options: 1) do nothing; 2) place herbicide at the base of the trees; or, 3) mulch around the trees.

Future drinking fountains should be handicap accessible.

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Recommendations: The City of Pittsburgh uses quality assurance specifications, as well as a standard tree planting detail, for all tree plantings. These resources, along with the City's list of recommended street tree species (which may be helpful when choosing trees along the edges of the park) are included in the Appendices of this Report.

Cost Analysis: Tree plantings – proper planting procedures included in cost of installed tree. Mulch for new trees in lawn areas ............................................................. $50 / tree Herbicide application for mature trees in lawn areas................................. $50 / tree New trees ................................................................................................. $800 / tree

Tree Plantings: For future trees, remove burlap and, ideally, rake the top few inches of soil off of the root ball to expose the top of the roots BEFORE the tree is installed. Planting holes for each tree should be shallower to account for the lessened height of the root ball. The "flare" at the bottom of the trunk, at the point where the trunk of the tree spreads out into the root system, should be visible on all planted trees. Mulch Trees: This report recommends that mulch rings be installed for new trees. Each with a radius equal to four times the diameter of the tree trunk around which they are installed, but no smaller than 4 feet in diameter. These mulch rings should be approximately 3 inches deep (as opposed to the thicker mulch installed on existing Pilot Project trees). A 3-inch deep mulch ring will pack down slightly, creating a low profile and a less suburban appearance. Avoid mulch “volcanoes” where mulch has been piled up against the trunk of the tree. Leave the root collar exposed. Provide organic mulch, we prefer double-shredded dark brown mulch. Do not place lawn clippings or leaf mulch. Mulch rings in lawn areas are absolutely needed to minimize tree damage from large riding mowers and to reduce drought stress during dry seasons. For mature trees, place an herbicide application to prevent turf growth next to the tree trunk. For trees in stone dust areas, do not provide any mulch or herbicide. New trees: Plant a variety of tree species to replace mature trees on the central allee in the park. The different, existing mature trees in the Pilot Project area, along with the newly-installed trees once they mature, will give the central allee visual variety and will increase overall resistance to tree pests. Historically one species of tree may have been used along the allee; current horticultural practice supports a variety of species to prevent the entire allee being attacked by a mold or pest that would kill all the trees.

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FLOWER / SHRUB PLANTINGS / FENCE/ MONUMENT LIGHTING

Professional Assessment: Decorative annual / perennial flower beds are visible in several historic photographs (such as that at right, c. 1911) in the Master Plan (p. 37), and such beds, even if significantly smaller than historic beds, will help to enhance focal points in the park. Such points include entrances, signage, monuments, and decorative fountains (not drinking fountains). The shrubbery installed at the base of the Hampton Battery statue today (pictured at lower right) is similar in form (height and density) as that shown in the historic photograph and should remain. At the pilot project, fencing was installed around the Hampton Battery to protect the monument and plantings around the monument. After some discussion, the committee suggested that fencing be removed (more historically accurate) once the flood lighting has been properly anchored. We can then see if fencing is necessary.

Possible Options: (Flower beds) According to input received at public meetings (notes from such meetings were provided by the AIC), some volunteer groups have offered to care for plant beds if they were installed. This would relieve C.O.P. maintenance crews of a time-consuming task and would help to create a sense of ownership in the park. Proposed plant beds, if installed, should consist of double-shredded bark mulch 3" deep, or composted leaf mulch to prevent weed growth. Plant bed edges should be shovel-cut edges for ease of maintenance.

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(Shrubbery / Fence / Monument Lighting) There are two options: 1) Leave the shrubbery as is, or 2) expand the existing shrubbery to conceal the existing floodlights. The floodlights have been a target of vandalism, possibly because they are so visible and close to the walkway. If shrubs were planted to conceal them, vandalism may be prevented. This concealment may, however, necessitate periodic pruning to ensure a clear path for the light emitted by each floodlight to the Memorial statue. Concealing the existing floodlights with shrubbery matching the existing shrubs in the plant bed around the Hampton Battery would mean filling the plant bed with shrubs, from the statue to the concrete curb forming the plant bed's outer edge. The 2002 Master Plan recommends removing fencing and installing plantings (p. 105). Pashek Associates recommends extra plantings to conceal the existing floodlights prior to any decision on the fence removal. Concealing the floodlights may prevent vandalism and thus show that no fence is needed.

Recommendations:

Cost Analysis: Double-shredded bark mulch (3" depth).....................................................$60 / c.y. Annuals / Perennials (bulbs) .................................................................. $3.00 / each Deciduous and Evergreen Shrubs (assumes 24" avg. height)........ $50.00 to $80.00

TURF AREAS

Professional Assessment: The lawn areas are in average condition, like many city parks. They suffer from lack of water during drought conditions, clay soils that don’t drain well, compaction from use and lack of fertilization. As part of this assessment, we took soil samples and submitted them to the Penn State Soils Testing Lab. They suggested that the lawn areas would benefit from increased Nitrogen at the rate of 2-3 pounds per 1000 square feet. This would “green-up” the lawn and encourage more vigorous growth. The test results suggested breaking this application into several smaller applications through the growing season.

Flower beds: Use volunteers to plant flower beds. Shrubbery / Fence / Monument Lighting: Expand shrubbery to conceal floodlights. Anchor floodlights with concrete footings. Remove fence.

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Possible Options: The possible options would be to do nothing to the turf or add Nitrogen to “green-up” the lawn.

Recommendations: The addition of Nitrogen may be beyond the normal capabilities of the City maintenance crews. This task may best be handled by a private contractor. There should be some discussion about the negative impact of applying supplements to lawns in public areas. Although safe, the perception (as opposed to reality) of applying additives might harm a child. We suggest that the turf areas remain as they currently are maintained.

Cost Analysis: None

SIGNS

Professional Assessment: The recently installed signs are beautiful. The artwork atop the sign is very tasteful, the sign colors are very aesthetically pleasing and visible during the day, and the height is optimum to maintain a pedestrian scale. If the signs were lower they may be prone to more vandalism, and if they were higher they may

dwarf surrounding features.

Possible Options:

(Signs) Continuing to use the same signage in future stages of the project is one option. Historic signs, such as these, can be slightly muted. It need not be extremely colorful or loud like signs aimed at commercial advertisement or wayfinding. Another option would be to modify the image, size, color, height, etc. to give the overall appearance of the signage a completely different feel.

Do nothing to the turf.

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(Sign lighting) The signs are currently not illuminated at night. One option would be to install vandal resistant floodlights for key signs.

Recommendations: We recommend using the existing signage design in future park development. Installing floodlights on existing and proposed signs will significantly emphasize the signs during night-time hours. However, floodlights near signs may be nearly impossible to protect from vandalism.

Cost Analysis: Floodlights (recessed, flush with lawn grade) ........................................ $750 / each Concrete Footing 12" x 12" x 36" depth (assuming mass installation) ............................................................ $50 per light

STREET CROSSING

Professional Assessment: The existing crosswalk at the corners of Cedar Avenue and East Ohio Street (pictured at left) provides handicapped access between the Pilot Project area and the North East Common. Both PennDOT and the City believe mid-block crossings are dangerous, especially in smaller blocks like this one.

Possible Options: 1) midblock crosswalk, or 2) no mid-block crosswalk

Signs: Use existing signage design for future phases.

Sign lighting: Install vandal-proof floodlights.

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Recommendations: We do not recommend a designated crosswalk in alignment with the central pathway. It would be dangerous.

Cost Analysis: None

STORMWATER DRAINAGE

Professional Assessment: The existing drainage system in the pilot project area is functional and drain grates are in satisfactory condition. Pipes were cleaned during the pilot project to remove existing partial clogs.

Possible Options: 1) do nothing, or 2) clean lines and replace grates as needed.

Recommendations: Pashek Associates recommends that stormwater drainage piping in future phases of implementation be cleaned by the most feasible methods possible. In addition, drain grates or structures should be replaced only where needed. These recommendations echo those made in the 2002 Master Plan (p. 141)

Cost Analysis: Pipe Cleaning .........................................................................$7 / linear foot of pipe Drain grates matching existing grates..................................................... $250 / each

Do not designate a mid-block crosswalk.

Clean storm lines and replace grates as needed.

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BIDDING The pilot project was funded largely by the City. To save costs, the city worked with the “B-contractor”, someone who publicly bid a variety of tasks on a bi-annual basis, and was selected by the city for their lower prices. Materials were purchased, when possible through existing city contracts with vendors. This avoided having to public bid the pilot project while meeting public bidding guidelines. An added benefit of working with the city’s B-contractor is that the City contractor was able to construct the project with bid documents that had less detail. Materials and methods of construction were discussed by the contractor, City representative and Landscape Architect to optimize the construction. Adjustments in the field were easy to make. The B-contractor was also familiar with working with other City crews and was able to coordinate those activities with his own. Assuming that the City will have less financial involvement and less project management participation, the Allegheny Commons Initiative should plan to develop more detailed construction documents and specifications and anticipate construction management needs. They will need to publicly bid the next phase. This will no doubt result in additional time and more consulting expense. Adjustments to the contract may be more challenging. During the Pilot project, any changes were simply negotiated and done. Under public bidding, any changes must also be negotiated and detailed documents provided to describe the changes to the contract. There may be an opportunity to purchase some materials on state contract, functioning like a City B-contract but through the state. This might save some money, and meet public bidding requirements.

MAINTENANCE A C.O.P. public works crew currently mows the lawn areas in the park and performs other maintains in the park. They can easily handle the larger maintenance tasks (mowing, tree removal / trash collection, etc.) but struggle to find time to complete smaller, time consuming tasks like raking stone dust or tree maintenance. Residents of the surrounding Community often have ideas to improve the park. These usually involve small amounts of additional maintenance, which many assume will be simply done by C.O.P. maintenance crews. The optimum scenario is to continue the current level of maintenance by C.O.P. crews while having volunteers and community groups assist by completing certain tasks such as:

m Raking stone dust m Sweeping stone dust from central paths m Weeding stone dust areas if necessary

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m Tending flower / plant beds m Creating / maintaining proposed shovel-cut edge between stone dust and lawn

Consistent completion of these tasks will help to foster a sense of community ownership in the park. Further, scheduled cleanups may increase safety by filling the park with more people, thus deterring some of the loitering in the park. Finally, a partnership between the Allegheny Commons Initiative, City Public Works crews, and volunteers will result in a beautifully maintained park.

DESIGN AND CONSTRUCTION PROCESS The City of Pittsburgh's extensive involvement in the Pilot Project via the use of B-Contractors resulted in a funding situation and design process that may not be possible on future phases of park development. Pashek Associates recommends the following timeline for design and construction be followed for future phases of the park. It should be noted that this timeline reflects an aggressive project schedule, and is based on a number of assumptions, such as: 1) all applications for grant funding will be successful; 2) all permit applications will be sent in during the preparation of construction documents; 3) the construction contract for the project will be awarded after public bid; 4) bidding will begin before permit approval is acquired, and all changes per permit regulations will be made via change order; and 5) weather will permit sufficient time for construction. 6) discussions with various regulating entities will take place prior to Construction Document preparation to determine the need for permits

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Time Line for Future Phases: 2008 April Submit DCNR Grant May Obtain Heinz Endowments Grant to begin Design Development June Obtain Survey of development area for this phase July - December Prepare Design Development documents by applying master plan and pilot project assessment conclusions to survey base December DCNR announces grant recipients; Define Scope of Project for construction 2009 January City of Pittsburgh Department of Public Works (DPW) remove trees

needing replaced January-June Prepare Construction Documents; submit preliminary drawings to DPW

and PennDOT (if necessary) for comment June Obtain Allegheny County Conservation District approval, NPDES or other

permits (if required) June Obtain City of Pittsburgh, Art Commission, and Historic Review

Commission approval and submit final drawings to DPW and PennDOT (if necessary) for approval

July Public Bidding of project August Award contract October-December Construction 2010 January – May Construction June Ribbon Cutting for Phase II

APPENDIX A:

Key Person Interviews

ALLEGHENY COMMONS Pilot Project Evaluation Key Person Interviews Eric Van Parks & Recreation Supervisor, City of Pittsburgh Dept. of Public Works -- Organizes weekly farmers market in Allegheny Commons Park 3/11/08 1) In discussions with farmers and visitors that attend the farmers market, what comments have you heard regarding park improvements that would benefit the market? Right now the paved walkway in the center of the park where we hold the market is 13 feet wide. Another 2 feet or so would make it more comfortable for farmers to fit vehicles and tables on the pavement while leaving more room for walkers and market shoppers. We have all farmers keep all wheels of their vehicles on the paved path so the adjacent turf isn't ruined. We also could use more lighting. 2) Have any changes in location within the park been discussed for the farmers market? A suggestion made by Chatham Landscape Architecture students (via a project working with the Northside Leadership Conference) involved moving the market to the western side of the east common, along Union Avenue. Farmers would park their vehicles on Union Avenue and a crushed limestone walkway would be installed there to accommodate tables and market shoppers. The location we have now is the only one that is accessible from a sufficient amount of public parking. Moving the market to that side of the park would eliminate some of that parking (along Union Ave.) and we need all the parking we can get to handle all the people who come to the farmers' market. 3) How many vendors and shoppers attend the farmers' market? We usually have 19 farmers selling produce at the market in Allegheny Commons. The last "hard count" of shoppers was done in 2004. That year, between 50,000 and 55,000 people attended the farmers market, which is held once a week for a 26-week season. Actually, the count was taken between mid-June and early September, so there is probably about 20% more shoppers that weren't counted. The season runs from Mother's Day until mid-November. 4) Is any type of signage needed? Where is the farmers' market advertised? We advertise the farmers' market in the Post Gazette, pass out residential flyers, and I post temporary signs along W. North St., Cedar Ave, and East Ohio Street adjacent to that side of the park. We have adequate signage for our purposes.

Mike Gable / John Samosky Deputy Director / Foreman, City of Pittsburgh Dept. of Public Works -- Public Works representatives that worked on pilot project 3/13/08 1) We have heard concerns about the stone dust bands. Committee members are worried about the edge of the limestone near the lawn, about displacement of limestone underneath the benches, grass growing in the limestone, and about the stone washing onto the paved path during rainstorms. What are your thoughts? I like the limestone dust. I think this part of the project was a success. I have heard issues with the width of the stone dust, but I think making the stone dust area narrower would result in every object (trees, fountains, light poles) being too close to the edge of the limestone. Also, lawn would then compete for water with the trees. Getting the stone off the pavement is a simple matter of improved maintenance. In future phases, the path will be more level so we won't have the same runoff problems. I think any type of edger between the grass and the limestone would eventually heave / move, and I think our best bet is to treat that edge like a plant bed edge. The limestone is going to have to be replenished every few years, so if the edge is a small trench, it will be easy to find when resurfacing. One alternative would be to use a material like that found in Schenley Park ("Sta-Lok" aggregate w/ polymer binder, or "Stabilizer", a polymer substance applied to secure existing aggregate, both as manufactured by Natural Sand Co.). It looks like aggregate but is solid like pavement. A little of the surface will wear off the top but it won't erode. Simply using bigger aggregate might work too. The stone wouldn't move. When the fountain was put in, kids scooped up handfuls of stone dust and clogged the drain so we had to take it apart. Bigger stone would prevent that. 2) What are your thoughts about the other items in the park (pipe rail, mulch, lights, benches, fountain, signage)? I think the benches work well - they look like the historic bench. I think we really need more of them - like in central park. There are benches all along the walkways so there's tons of places to sit. I think we need that here. I know there are complaints about undesirables in the park, but if the people in the community would come out and use the park more -- schedule events, etc. -- there would be less undesirables loitering because of the increased use. The pipe rail looks great. The mulch is not ideal but it serves its purpose, especially since it is now packed down a little. When it was first installed, it was loose and could be kicked around onto sidewalks pretty easy. Now it’s better. We need to extend the mulch out to the mulch rings of trees that are within 6 or 7 feet of the pipe rail because maintenance crews can't fit their mower between the rail and tree. Filling that area with mulch would eliminate the need to do so. The light fixtures are great I think. There was a problem with the lids of a couple fixtures flying off during wind storms, but once Allegheny Electric came out and fixed them, there were no more

problems. I think the Metal Halide light (bright, white) is needed here. The High-Pressure Sodium bulbs set a nice mood, but this park needs to be bright and safe, not dimly lit. Our crews are supposed to come out shortly and install a more secure mounting for the uplights around the Hampton Battery Memorial. Vandals pulled the lights out of the ground during the winter, so we put sandbags on them to secure them temporarily until new mountings could be installed. I think that not every fountain in the park needs to be handicapped accessible, and not every fountain has to match the historical fountains. Perhaps a few of the fountains in future phases can be the more modern, cantilevered type under which a wheelchair can roll. I really like the artwork on the signage, and think the colors are great. 3) What do you think of the paved pathway surface? I think it's functional. Yes, there are some irregularities but overall it doesn't look THAT bad. I think what the committee is looking for is more of a grainy look (similar to exposed aggregate concrete) but not having stones protruding upwards from the surface. The older, worn asphalt on Cedar Avenue is a perfect example (Rozzi offered the example of pathways in the West common, using asphalt with pea gravel mix instead of typical aggregate) I also think having a test section or square would be ideal for future projects so everyone can get an idea what it will look like and the contractor will learn the process of installing the special paving. 4) Do you think the use of the City's B-contractors will be feasible for future phases of this project? I can't predict whether we'll have money to put toward future projects, so the B-contractors may not be an option. The City put a lot of money toward the pilot project, and the next phase is two or three times that. I think it'll be a better idea for that phase to be put out to bid. 5) Are there any other concerns you have? The larger trees in the park need larger mulch rings. A 2' radius mulch ring is fine on a small tree, but as that tree gets older, the mulch ring must grow with it. Expanding a mulch ring is as easy as spraying the grass to kill it, then digging up the sod and placing mulch. Also, water service access is needed about every 100' or 150' if we need to water plants or irrigate. Right now there are only two water service access panels along the central walkway in the pilot project. They are closer to the Hampton Battery Memorial, which makes reaching the plants along East Ohio Street difficult b/c crews have to move 200+ feet of hose. Such water service access (hose bibs) would be needed wherever we have to water plants. Rozzi pointed out that the master plan for the park calls for hose bibs at all plant beds.

David Jahn City Forester, City of Pittsburgh Dept. of Public Works --with-- George Pegher Consulting Arborist -- worked on pilot project 3/13/08 1) There are concerns that the limestone dust bands (15' width) on either side of the asphalt walkway, as well as the limestone base for the walkway itself, will be detrimental to the trees planted there. In your opinion can the limestone be placed around the trees near the central walkway in other parts of the park? I think the 15’ band will be OK provided trees are planted at the correct depth, and the bands do not increase in width. The roots can find plenty of non-alkaline soil outside the band if it is needed for survival and thriving. I make this comment with the assumption that the trees presently planted inside the bands are thriving. If this is a valid statement, then bands elsewhere in the park should also be acceptable. 2) Some of the trees planted during the pilot project had 12" or more mulch around their bases, causing slight rot at the base of the trunk. George Pegher, the consulting arborist I talked with a few times on the pilot project, seems to think that b/c there is such a thick layer of mulch and b/c the rootballs were buried too deep, the entire root balls of the newly-planted trees are below the crushed limestone placed on either side of the central walkway. I can't see any visible effects on the trees, but I'm not an arborist! Any thoughts? These trees are buried a little too deep. What happens is a contractor installs the rootball in the ground before peeling back the burlap bag and wire mesh. Then when the contractor shaves off some of the dirt on top of the rootball (as is customary), they don't adjust the depth of the rootball and the trees are planted too deep. At the base of every new tree you should see the top of the "flare" of the roots coming off of the trunk. If you can't see this, the tree is planted too deep. 3) Would you recommend that in future phases, the City's B-contractors be used to install trees or would another contractor specializing solely in plantings be used? While you are not compelled to use them, it should be noted that the pre-qualified B-304 tree planting contractors are up to date in their understanding of our city standards and compliance will be easier to obtain from them. One of the central conditions to our protocol is planting depth. Unfortunately, there has been a trend in nursery production in recent years to bury the trees in the root balls, so we mandate that trunk root flare be visible at finished planting depth. This often necessitates removal of soil from the top of the root ball and adjusting planting depth upward. It has been a struggle to educate the contractors, but the battle has largely been won so it makes some sense to utilize the contractors who are so indoctrinated. Having said that, if someone outside city government is running the planting contract, choice of contractor belongs to them. I will be more engaged in the next tree planting effort in AC, trying to avoid pitfalls like planting too deep. 4) Tree species on the central allee in the park (along central walkway) include 'Village Green' Japanese zelkova, silver linden, prospector elm hybrid, oaks, and ginkgos. Historically, this allee may

have been a single species but it was decided to plant different species for disease protection and botanical variety. Do you have any suggestions for which trees should be used to "fill in the gaps" left by trees already dead / removed or trees that will be removed for safety reasons during future phases? (as an example, one or two large trees were removed from the pilot project site because they were hollow and were a risk to drop large limbs during a wind storm). The larger (read: majestic) the better for a central allee, so Elm/Oak/Ginkgo are desirable in odd groups of 3-5 before genus change. Any of the trees you mention are fine. Knowing that all trees someday will need replacing, I would ask for a genus change where even a single space becomes open. A few more of the same genus can be added as more spaces appear over time. The only time trees ever look approximately the same is when they are newly planted. The tradeoff to not having rows of a single species is a good one, when we consider the avoided devastation from losses of a species to disease or insect infestation. 5) Are there any other general design issues we should keep in mind during future improvements in the park? The mature existing tree (a 24"+ diameter ginkgo) on the eastern side of the central allee nearest to the Hampton Battery Memorial is very close to the paved central path (2 to 3 feet). (Rozzi explained that the contractors cut several large roots in order to place the pavement edge in its current location). In the future, the pavement edge should react more to the trees. In other areas of the park (as observed during site visit), a 6-foot radius from the trunk of each existing tree adjacent to the central paved path should be maintained as mulch or limestone dust. The paved path will be wide enough and should allow this 6' space for protection of sensitive main roots. Also, it is a good idea to connect mulched areas around trees to adjacent edges (pipe rail mulch bed or limestone dust area edge) if the trees are within 5 or 6 feet of that edge. This will eliminate the need for mowing small strips of grass between the tree and edge. Tony Pampena President / Owner, Tony Pampena Construction -- General Contractor on pilot project (also on City's B-Contractor List 3-13-08 1) What are your thoughts on creating small mock-up / test sections of decorative paving surface for the central paved walkway? Unless there are established / practiced material and procedural specifications, it would be a good idea to have an off-site experimentation area. Whether that be at a contractor's property, or at a City materials storage area, would be up to the City. Several different installation methods could be tried, as well as several different aggregates, a method is found that works. 2) Being that the material treatment used for the paved walkways in the pilot project was relatively unfamiliar to all involved with its design and installation, the end result quality was less than expected. Do you have any suggestions for attaining the exposed aggregate / weathered look that was desired on the central pathway?

The specification for the paved walkway in the pilot project called for far too much material to be rolled into the surface of the asphalt. What happened was the amount of material, and the presence of the dust in the aggregate, prevented anything from being imbedded in the asphalt. The gradation of the aggregate was good, but having fines (dust /small particles) in with the stone should be avoided. Also, it may work to lightly roll the asphalt tack coat / setting bed first, then place the clean stone to be exposed, then go over the surface again with a roller (possibly a vibratory roller). This would adequately set those stones in the setting bed. Marion Pressley President, Pressley Associates, Inc. -- Landscape Architecture firm that wrote Master Plan for Allegheny Commons in 2002 3/18/08

1) I was wondering if you could provide some input into our evaluation. we are interviewing several people that were involved with the pilot project in one form or another, and we feel that your thoughts on some of the issues with the park will be essential to the evaluation. The committee we are working with for the project has voiced some concerns over some of the design details that have and haven't worked in the pilot project. In addition, we have a few concerns after visiting the park in the last week or so. They include the following:

STONEDUST:

• grass is beginning to take root in stone dust areas -- possible solution: increase maintenance, blow grass clippings away from stone dust when mowing

Response: Yes the stone dust needs maintenance on a regular basis including raking and compacting. I am not sure it had satisfactory compaction when it first went in. We usually ask for four inches of material compacted to three inches.

Grass clippings should not be blown on to it anymore then they should be blown on to a 3/8” inch peastone or other similar material in which grass could get a hold. I believe that stone dust is a material that is not used in Pittsburgh and I think that is the reason its maintenance has become an issue. Leaves in the fall need to be removed.

One part of this detail that we discussed during the master planning was the use of a steel or wood edge to contain the stone dust. The cost is high for these edges and they can move up from frost heave so they too have a maintenance cost, but they of course help prevent the adjacent grass growing into the stonedust and keep a clean precise line. They will not solve the grass clippings issue. In a later question you talk about cobbles as an edging. Are you talking about the limestone ones you have in Pittsburgh?

SPEC: Stonedust shall be placed in one (1) layer of four (4") inches loose depth and then compacted by means of vibrator to achieve a 95% minimum compaction rate consistent throughout the stonedust. Final surface of stone shall be left one-eighth (1/8”) inch higher than adjacent surfaces to allow for settlement.

• severe "rutting" is taking place in the stonedust areas right front of benches (from people kicking stone dust with their feet) -- possible solution: Belgian block / cobble stone bases under benches

Response: This is part of the maintenance just as you would need to rake material such as sand or woodchips or fiber-mulch in a playground. In a playground the material at swings and at the bottom of slides needs maintenance on a regular basis. I would guess at least twice a year; once during spring clean-up and in the fall.

Cars and trucks driving on it can also cause ruts.

I find that cobblestones are not the most comfortable material unless they are actually precisely cut granite units sawn and thermal finished. We have also used brick in this way. We have even put a concrete pad under benches to act as a footing as well as a uniform hard surface.

In the case of the Commons, the informality of placing the benches in the stonedust rather then into the path was the idea. It was a space consideration. We thought that people putting their feet out as they sit would take up part of the paving width. Also that it is a more passive material. See Figure 20 (1911) in the master plan. We wanted to pull the benches back under the trees. If we are going to rethink that, we should go to Figure 20 and have them set in the paths again.

• stonedust is washing into grass and onto paved central walkway -- possible solutions: increased sweeping on central walkway, install a single row of Belgian block as an edging between stonedust and lawn. These could possibly serve as memorial donor items and be engraved.

Response: Same as the answer above regarding edgers and Belgian block. If you are, I am not sure these will work in terms of engraving them for donors. My experience with them at PSP is that they are very rough, and another consideration is that they are also not a material that was used historically in the Commons. The ones in the Battery area were much later and not of the Primary period of Significance of the site.

PAVED WALKWAY

• The asphalt with limestone chip surfacing did not turn out in the intended manner. -- Possible solutions: Utilize different materials in the rest of the park (i.e. asphalt mix including pea gravel instead of typical aggregate - see attached photo).

Response: The chip and seal is not something that is used in Pittsburgh for paths so locating a Contractor for this was problematic. We use it all the time in Boston for historic sites since it gives the appearance of a soft stone paving. The person really has to know what they are doing with the temperatures and the fact that the stone has to be chips no sandy fines and that it has to be clean are all issues. They also cannot over roll it or it breaks it up into fines. What I see in the photographs is definitely caused by all of these issues.

I have been trying to use your rustic terrazzo sidewalks in other areas including Boston and find the Contractor’s just do not know the material or the methodology. So lesson learned is to use what the contractor’s in the area can do easily. I, therefore, agree that we should go back to what is on the other paths, which I would call and open graded aggregate pavement. It looks like what we would use as a base course for a bituminous walk or even a black base which is open graded aggregate penetrated with bitumen. That is one reason I thought that the rolled stone was possible when I saw something in the same vocabulary. I would not consider the additive to be gravel, because gravel has too many fines, but would think it was an aggregate that is a sharp crushed stone.

• Sharp corners in the walkway don't match the rounded corners in other parts of park. -- Possible solutions: provide rounded corners at all intersections of newly-constructed pathways in future phases.

Response: I am not sure how they ended up sharp. We show curves on the master plan

SIGNAGE / PLANT BEDS

• The new signage is beautiful but the lettering should be brighter (see attached pic)

Response: I did not see an attached pic. Not sure brighter is better. Historic signs are usually toned down. They are usually not in the mode of the Western Conservancy signs around town for plantings maintained by abutters.

• The master plan recommends flower beds at focal points (entrances, monuments, fountains, signage, etc.) - should these be planted and maintained with perennial bright yet simple floral arrangements? or should more shrubs be used?

Response: The old photos which you can see in the master plan are really annuals or in any case plants treated as seasonal plantings. They are Victorian bedding out see figure 15 at Armstrong Monument or figure 19 at the Northeast Fountain in East Common. They should not be shrubs or perennials, but should be seasonal in the spirit of the original planting beds. Shrubs and perennials are too suburban and not appropriate if we are trying to do historical plantings. The current shrubs at the Hampton Battery are not in the historic mode, see figures 22 and 23 at Hampton Battery. Yes they are a little bit much and should be toned down; we do not need the elk, although the Elk Fountain was originally below it and of course relates to the Elk’s Lodge opposite.

2) Any other thoughts or issues that we haven't discussed?

I think one item that is not on your list is the post and rail fence. I do not think the area under the fence works well in terms of maintenance. I think it should be paved under the posts and rails to make maintenance easier. Along Cedar Street it would have worked with the very narrow concrete walk along that edge if they were set with concrete. I also think a flat black paint would have been better then the very shinny finish, which is a modern treatment.

Christina Schmidlapp Northside Leadership Conference -- Project Manager for Pilot Project 3/18/08 1) Thus far, I've discussed different materials and processes used during the pilot project with several individuals. I'd like to just discuss some of these and get your take on each. They include: STONE DUST: I know some feel that the edge between the stone dust and lawn is hideous, but I really don't think it's that much of a problem. In visiting parks in London (i.e. Hyde Park), "wavy", uneven edges such as the one in the pilot project were visible everywhere. As for stone dust material itself, I think we should explore options (i.e. bigger aggregate). Some have said that we should try some type of granite dust instead - that was a material used in the northeast states. (Rozzi explained that a bigger aggregate might mean less movement during rainstorms). The issue of the stone dust moving underneath the benches because of people swinging their feet is a small one. BENCHES: I love the benches, and if the City is ok with the finish (which is wearing off in some spots) then I'm ok with it. I don't think it needs to be perfect. I was skeptical of the donor plaque idea at first, but because the center railing is installed on all the benches, one can't really sit and lean back directly on the plaque. It looks great. Originally I believe the Master Plan called for two different sizes of bench, but they were not specified for the pilot project, so I don't think that issue is very relevant yet. Maybe in future phases. One other issue with the benches is exactly where they were historically. Some want to move them back from the central path so they are in-line with the trees. (Rozzi explained that the historic photo on the cover of the master plan shows benches on the paved central walkway, with NO stone dust apron. Lawn extends to the paved walkway). In future phases, if no stone dust is put in and benches are installed in the same place, the area in front of them will become mud, so that's a problem. I do think that there should be more benches so people have options on where to sit -- not just in small groups near other people. In future phases we may want to spread the benches out, because we can always come back and in-fill more benches when funding is available. I wholeheartedly agree with the idea that more programmed activities in the park would fill the park with people and would keep out undesirables. TREES: I know about the ongoing debate about the mulch around the trees. Some think it should be replenished periodically (from a maintenance-only standpoint), and some think it should be allowed to disintegrate so the stone dust and lawn extend to the tree trunk (historically correct). I tend to agree with the historically-correct view, but I can see a valid argument from the other side -- that in the past,

maintenance crews didn't know how to properly care for plants as we do today. Plus, eliminating the mulch rings in the lawn areas would create a risk of each tree being hit by a mower. Alida Baker is starting to get information on the treevitalize program that is being instituted in Western Pennsylvania via DCNR. Through this program, we may be able to get a couple of the trees in the pilot project replaced. (One tree died, two have been vandalized, thus their long-term health is questionnable). PIPE RAIL / MULCH: I think the mulch beneath the pipe rail worked and was very cost-efficient. I also think the goal of having the pipe rail completely surround the park could be modified. If the barrier was installed near the main entrances to the park (corners, etc.), then large distances between these entrances could be left open, possibly to be installed when funding is available. The pipe rail at the corners would create the aesthetic everyone wants, and would serve most of its purpose. It won't hinder any access to the park. LIGHT FIXTURES: I think the light fixtures are lovely-looking. I have heard complaints about them being too bright, but none of these complaints are from folks living adjacent to the pilot project. I do suggest that we install one diffuser (a mechanism that de-intensifies the light coming from the bulbs that are already installed) on one light pole to see how it looks. Then, if that looks ok, we can go ahead with them on the rest of the installed light poles and order them for future phases as well. If everyone decides that the diffuser doesn't work, we'll just remove it. The idea of uplighting the signage in the park is ok, but I think the signage is fine right now. Then again, I was skeptical of uplighting the Hampton Battery memorial, and I thought it looked great once it was uplit. SIGNAGE: I think the signs are great, I like the height of the sign and I like the sturdy base, even though it was a 2nd choice. Those that say the text needs to be brighter may not realize that it's already been lightened. We already had Landesberg come out and re-paint the main lettering to lighten it once. TRASH RECEPTACLES: I like the size of the trash receptacles - I don't think they have to be the bigger size you see on the streets. These don't ever seem to be overflowing with trash. (Rozzi explained the possible need for lids, as identified by the City maintenance crew). I agree with trying out lids on certain trash cans to see if it deters neighbors from stuffing entire bags of garbage in the cans. I also believe this is the size that the Master Plan specified. PAVED WALKWAY: I think the pavement is not good. It's uneven and we should either take it out and redo it, or if that's not financially feasible, we should just make sure we get something better on future phases. We

definitely need to do some type of mock-up off the site so that the contractor is familiar with the process of installation and the aesthetic goal of the material. LAWN / TURF: The turf in the pilot project wasn't really an emphasis since it was in pretty good shape. Such is not the case elsewhere in the park. Should different grass seed mixes (i.e. shade mixes, etc.) be explored for deep shade areas that are now almost bare soil? BIDDING: I think that without City funding, the NSLC should handle all the bidding details for future projects. I really think Alida Baker can handle that (RFP's, etc.). That will be needed since the City doesn't appear to have the money to support future phases the way they did the pilot project. CROSSING: Although the crossing of East Ohio Street at the central promenade was not addressed as part of the pilot project, it must be included in the next phase. We could perhaps try something simple w/o doing a traffic study or large engineering project to determine how to implement the crossing. We could try something like plastic turtles crossing the road, or possibly something like the crossing near Citizens Bank on East Ohio Street. We could try this before actually getting the city to come out and create curb cut ramps. (Rozzi explained that the curb cuts may not be necessary since handicapped access is already available at the corners of that block (at existing sidewalk ramps)). SIDEWALKS: I think the treatment of the sidewalk along East Ohio Street for the pilot project was great (narrowing it except for at the intersection with the central walkway in the park and at the corner of East Ohio St. / Cedar Ave.) MAINTENANCE: The community surrounding the park cannot simply ask for increased maintenance all around the park and expect the city to increase manpower and do everything. One way to get some thing done is to organize volunteer labor to take care of the park. Residents of each neighborhood will take care of certain maintenance tasks in the portion of the park near their homes. These could include: 1) doing the edging between lawn and stone dust; 2) tending to flower beds; 3) sweeping stone dust off of central path and into depressions near benches; 4) raking stone dust to remove leaves and eliminate grass rooting. The community needs to be more involved. Lisa Ceoffe Arborist, City of Pittsburgh -- interviewed via email by NSLC 3-27-08 Email from Alida Baker, NSLC: We in Allegheny Commons are currently evaluating the features we placed in the East Common, to determine whether they should be replicated in the rest of the park. One of the issues that came up

recently was mulch mounds around the trees that are in the lawns. It was suggested at one of the community presentations that mulch mounds look rather suburban, and not appropriate for a historic park. One of the purposes of the ring around the tree is protection from the lawn mowers. I understand also that mulch plays a role in the health of the tree. My question to the two of you – what are some other options for achieving those goals that might look a little different? Maybe you have ideas about that, or maybe you can direct me to another resource. Email Response: Well mulch rings do stand out a little in a park setting. The best thing I think is to remove the turf or grass area around the tree by hand. This kind of gives you a bit of a boundary so to speak and apply fresh topsoil sparingly. I think the use of mulch is ok if its used sparingly. I think it tends to be applied on to thick and thats what is unattractive. I really can't think of any other treatment other than understory type planting. You could try a combination of mulch/soil on some and designate a few for accent maybe at the entries or along pathways. You could use seasonal plants/bulbs/ ect... Its more costly but very attractive. Matthew Erb Friends of the Pittsburgh Urban Forest -- interviewed via email by NSLC 3-27-08 Email from Alida Baker, NSLC: We in Allegheny Commons are currently evaluating the features we placed in the East Common, to determine whether they should be replicated in the rest of the park. One of the issues that came up recently was mulch mounds around the trees that are in the lawns. It was suggested at one of the community presentations that mulch mounds look rather suburban, and not appropriate for a historic park. One of the purposes of the ring around the tree is protection from the lawn mowers. I understand also that mulch plays a role in the health of the tree. My question to the two of you – what are some other options for achieving those goals that might look a little different? Maybe you have ideas about that, or maybe you can direct me to another resource. Email Response: I can see the point that the trees look somewhat suburban when mulched in the park. I think Lisa has a good point that if the mulch is mounded to high, it exaggerates the problem. Also proportion is key, if the mulch ring is too small it looks inappropriate, by having a very large ring, the size compliments the size of the tree. When trees are grown in groups, mulching the entire group in one bed can be effective. Overall mulch is sorely needed on our park trees as is additional landscape, hostas, bulbs and shrubs could all enhance the beauty of the mulch and the park. Another thought is that the park is a very formal setting, perhaps by establishing the mulched area using an edging of Belgian block, rock, or steel edging would add the formality needed.

More over this a cultural issue, just like tree topping was once an acceptable practice that people thought was attractive. People aren't used to seeing trees mulched, but know that we know it is the right thing to do, we have to change people's perceptions. Joe Santangelo President, Santangelo & Lindsay -- Electrical Engineering Firm that worked on Pilot Project 4/8/08 1) Could any of the electrical work been done differently for the Pilot Project? I think our work for the project was pretty unobtrusive. All the electric was underground, with the only visible component being a junction box, and maybe an access panel also. There was plenty of power available at the pool house. This was readily available for that portion of the park, but I imagine there are other sources of power in other areas of the park. 2) What did you think of the light fixtures for the Pilot Project? We have heard differing opinions on them so far. Some say the bright light is great for safety in the park, others want a more "cozy" feel. However, none of the complaints about brightness came from people living next to that portion of the park. I'm sorry to hear about the dissention. I think the lighting calculations for the Pilot Project were good as far as consistency and brightness for safety. Those are the most important things. On one of our past projects, in the Borough of Beaver, the client wanted to shorten light poles and cut wattage in order to create that "cozy" feel on street lamp posts. Now when you drive through that street on a rainy night, the light doesn't reach the center of the street and its dangerous. That was a huge mistake by the client, in my opinion. Nowadays you get a lot of light for less money. There is no reason not to fully illuminate the park. I found a note from the project indicating that the City's Department of Public Works wanted to emphasize brightness / performance over feel in regards to the lighting. Your committee may not like that statement but I have to agree with it.

APPENDIX B:

Project Meeting Notes

Comments from Joint meeting of Allegheny Commons, East Commons Pilot Project Assessment February 25, 6:00pm

1. Informational signs were done well – suggested the contrast between the letters and background be increased or the letters made larger. The lime green color was not a favorite of some.

2. There was much discussion about bench placement and quantity. Although there was not unanimity, the suggestion was to keep the same number of benches but make sure they are not across from each other to disperse the larger crowd of folks hanging around the benches and blocking the walk. It was noticed that trenches were forming from feet dragging in the gravel in front of the benches. It was decided that additional maintenance might solve this concern.

3. Revisit the “rules” signs, several suggestions were made as to content; these signs should not be located at the entrances into the park; a more friendly message should be located there.

4. There was much discussion about the width of the pathway. There was not total agreement on what to do. Most wanted a reduction in the width, accomplished by reducing the aggregate width on each side. This may mean that existing trees might be outside the gravel band or the gravel band edge might have to meander to include all of the tree trunk and surface roots.

5. Some have suggested that the lime dust aggregate might be damaging the trees by altering the ph of the soil.

6. There was concern about the weeds growing in the aggregate bands. It was suggested that there may need to be increased maintenance to keep the weeds out. Weeds usually grow from the top and can be prevented by lightly raking the gravel infrequently. There also was concern that the gravel eroded, forming gullies that washed fine aggregate onto the walk and was unattractive.

7. Regarding the asphalt section of the pathways, it was suggested that portions of the asphalt pathway in West Park are a more attractive surface treatment than what we currently have in the pilot project. It looks like Pea gravel was mixed into the asphalt surface.

8. It was noted that in future phases we wanted to look at the possibility of doing a pervious asphalt paving to allow rainwater to get to the ground through the pavement. This might change the texture of the surface (more coarse).

9. Although not unanimous, the consensus was that the railing added value to the park. If budgetary constraints limited the railing, maybe it could be installed at all of the park entrances and left out in other areas, directing traffic to the paths. It was suggested that in the future the wood mulch under the railing be replaced to match the aggregate bands along the central pathway.

10. The fencing around the Hampton Battery should be removed. Nothing should replace it for now but a railing or historically correct fencing section may need

to be added in the future if park visitors damage the lighting, shrubbery, cannon or statue.

11. All liked the drinking fountain but some were concerned about the Handicap accessibility of the fountain. This would need to be integrated into future drinking fountains.

12. All liked the light fixtures but the brightness of the light was questioned. Apparently there were to be sconces that softened the light source without reducing the illumination of the walk. It also appears that as bulbs have burned out, the wrong bulbs have been installed providing a different color. It was also noted that lately, none of the lights were working. Finally, it was noted that in high winds, some of the light fixture tops were blown off. Future lights should be better secured.

13. There was discussion about the treatment of the edge between the grass and stone band. Some thought a paving edger would be useful. Some recognized that frost heave could render the edge material into a tripping hazard and add cost to the project.

Comments from Meeting of Allegheny Commons Subcommittee East Commons Pilot Project Assessment April 9, noon @ NSLC Offices Attendees: John Francona Lynn Glorieux Alida Baker Andrea Lavin Jeff King Katie Molnar Marilyn Detwiler Jim Pashek Vince Rozzi Vince Rozzi of Pashek Associates briefly reviewed portions of the Draft Evaluation Report, include an explanation of project analysis and preliminary recommendations. Comments made on the various preliminary recommendations are summarized below: Paved Central Walkway

1. Trying to use the stone dust may not be worth the risk. That method was expensive on the pilot project and the result wasn't what we wanted.

2. We shouldn't discount the "green" approach. Porous pavement should be addressed as an possible solution.

3. An increase in aggregate sub-base beneath the porous pavement may be the answer to solving the problem of freeze-thaw. If the water has more pore space to fill beneath the pavement, it won't be stuck within the pavement.

4. Rozzi stated that if Pashek Associates were to recommend one material to use, it would be asphalt with a pea gravel aggregate (as seen in West Common)

5. I'd like to see a diagram, notes, and description on porous pavement in the report.

Stone Dust

1. Width has been an issue. Could the recommendation be that the MAXIMUM width is 15 feet?

2. The total width of the central path and stone dust seems really wide. If we can achieve color variation between the asphalt and the stone dust, it would lessen that effect.

3. We should put darkened asphalt color in the specs in the future so we assure that contrast.

4. Maybe we should adjust the width of the stone dust per the position of the allee trees in each part of the park.

5. I like the formal rigid edge on the stone dust. I didn't at first, but I grew to like it.

6. Using the larger stones sounds like a good idea to solve the erosion / movement problem with the existing dust.

7. The Large stone size and polymer probably aren't needed at the same time. Using the larger stone would solve most of the maintenance problems we have with the dust now. The polymer would be best used with the existing size of stone dust.

8. We need to see a sample of size 1A gravel so we can see how big the stones are.

9. If the polymer is a plastic or toxic substance we shouldn't consider using it (Rozzi explained that Natural Sand Co., the manufacturer of the polymer, claims it is all-natural.

10. There are some big white stones mixed in with the stone dust now. These were mixed in when the city maintenance crews made ruts in the stone dust with their vehicles then filled them in with different stone. These stones don't sink in the ruts, they stick up and are very visible.

11. The shovel-cut edge sounds like something that volunteers can do. Pipe Rail Barrier / Mulch

1. The mulch between the barrier and close trees is a good idea. 2. Who will re-mulch the areas under the barrier? Some concrete footings for the

corner posts are showing thru the mulch. 3. The city may not provide as high a quality of mulch as would be provided by

a commercial seller. 4. I did not realize the glossy finish on the barrier wasn't historic.

APPENDIX C:

City of Pittsburgh Tree Planting Standards

RECOMMENDED SPECIES LIST NOVEMBER 15, 2007

Prepared by Forestry Division City of Pittsburgh 412-665-3625

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RECOMMENDED TREE SPECIES FOR PITTSBURGH’S STREETS There are two main categories; Shade Trees where no overhead utilities conflict with tree growth, and Utility Trees where overhead utilities call for shorter trees. The Utility Tree section has 2 parts to account for the occasional situation where wires are 25’ or higher above ground. SHADE TREES Trees in the Shade Tree category should be planted where no overhead utilities exist. Shade trees are the most desirable size of tree for planting, and should be used at all times in the absence of overhead wires. Acer rubrum ‘Franksred’ - Red Sunset Red Maple (do not use within 5’ of sidewalks; aggressive root system) Acer x freemanni ‘Celzam’ - Celebration Freeman Maple (do not use within 5’ of sidewalks; aggressive root system) Aesculus x carnea ‘Briotii’ - Ruby Red Horsechestnut (less mid-summer scorch than hippocastanum Cercidiphyllum japonecum Tree Form- Katsura Tree (requires more water during establishment years than most other trees) Corylus colurna (tree form) - Turkish Hazel or Turkish Filbert Eucommia ulmoides - Hardy Rubber Tree (not pretty but can be useful) Ginkgo biloba (any male variety) - Ginkgo (male example is Princeton Sentry) Gleditsia triacanthos (any thornless, seedless, variety) - Honeylocust Gymnocladus dioicus (male variety only) - Kentucky Coffeetree Liriodendron tulipifera - Tulip Tree (open lawn or large parking island) Metasequoia glytostroboides – Dawn Redwood (requires larger than usual pit if used as a street tree, or use in open planting areas) Nyssa sylvatica - Blackgum Ostrya virginiana – American Hophornbeam Platanus x acerifolia ‘Bloodgood’ - Bloodgood London Planetree Quercus bicolor - Swamp White Oak Quercus macrocarpa – Bur Oak Quercus rubra - Northern Red Oak Quercus palustris - Pin Oak Sophora japonica - Scholartree (flower issues make this an open space tree not suited to sidewalk use) Taxodium distichum – Baldcypress (for large areas) Tilia tomentosa - Silver Linden (open space tree) Ulmus parvifolia – Lacebark Elm/Chinese Elm Ulmus Hybrids – disease resistant trees like ‘Homestead’, ‘Pioneer’, ‘Accolade’, ‘Frontier’, ‘Liberty’ and ‘Urban’. Zelkova serrata – Zelkova (‘Green Vase’ is not recommended in commercial areas where it may block signage)

RECOMMENDED SPECIES LIST NOVEMBER 15, 2007

Prepared by Forestry Division City of Pittsburgh 412-665-3625

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UTILITY-COMPATIBLE TREES – Group A (under-wire use) Group A applies to most plantings under utility lines. This is necessary because most wires are less than 25’ above ground. Where possible, offset trees so they are not directly under the wires. Acer ginnala – Amur Maple 15’-20’ Acer tataricum – Tatarian maple 15’-25’ Crataegus crus-galli var.‘Inermis’ – Thornless cockspur hawthorn 15’-20’ Crataegus laevigata ‘Superba’ – Crimson Cloud hawthorn (tree form) 15’-20’ Magnolia stellata – Star Magnolia (tree form) 10’-20’ Malus cultivars – crabapple (disease resistance emphasized) all under 22’

Adams, Amsalzam, Centurion, Donald Wyman, Harvest Gold, Prairifire, Professor Sprenger, Red Jewel, Robinson, Sentinel, Sugar Tyme, Strawberry Parfait (always specify tree form for crabapple selection) (Fruit makes Malus undesirable in commercial areas)

Malus floribunda – Japanese flowering crabapple under 25’ Malus sieboldii x zumi ‘Calocarpa’ – Zumi crabapple under 25’ Malus ‘Spring Snow’ tree form – Spring Snow Crabapple 15-20’ (fruit makes Malus undesireable in commercial areas) Group B (use only under wires 25’ and higher) Group B applies only to utility plantings where the bottom wire is over 25’ above ground. Where possible, offset trees so they are not directly under the wires. Acer buergeranum – Trident Maple (tree form) 20-30’ Acer campestre – Hedge maple (tree form) 25’-40’ Acer campestre ‘Evelyn’ – Queen Elizabeth hedge maple 30’-40’ Acer griseum – Paperbark Maple 25’-35’ Amelanchier laevis ‘Cumulus’ or “Majestic’ – Apple Serviceberry 20’-30’ Amelanchier x grandiflora – Serviceberry (many cultivars) 20’-30’ Carpinus betulus “Fastigiata’ – European Hornbeam (tree form) 30’-40’ Carpinus caroliniana – American Hornbeam (useful in full shade) 20-35’ Cercis canadensis – Eastern Redbud 25’-30’ Cornus kousa – Kousa Dogwood (esp. Rutgers hybrids) 20’-30’ Koelreuteria paniculata - Goldenrain Tree 25’–40’ Magnolia ‘Galaxy’ – Galaxy Magnolia (tree form) 20’-30’ Phellodendron amurense – Amur Corktree 30’-40’ Prunus sargentii – ‘Columnar’ – Sargent cherry 30’ Prunus serrulata ‘Amanogawa’, ‘Kwanzan’ – Japanese flowering cherry 25’-35’ Prunus virginiana ‘Shubert’ – Shubert Chokecherry 20’-30’ Sorbus species – Mountain Ash 15’-35’ (in limited quantities) Syringa reticulata ‘Summer Snow’, ‘Ivory Silk’ – Japanese Tree lilac 20’-25’

RECOMMENDED SPECIES LIST NOVEMBER 15, 2007

Prepared by Forestry Division City of Pittsburgh 412-665-3625

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Trees planted on city property shall be:

• 2” caliper (minimum) measured 6” above the root ball; • set rootball level slightly above soil grade (1-2”), finished soil grade being 2”

below top of sidewalk (see Tree Planting Detail). • mulched with 2” of shredded wood mulch for weed control; • stake trees just below the first branch with 1”-3” wide polypropylene straps (2 per

tree on opposite sides of tree, connecting from tree to stake horizontally). DO NOT use rope or wire through a hose. ArborTie is an acceptable product.

• Remove all staking materials after one (1) year, or as otherwise directed by the City Forester.

• Planting beds shall measure a minimum of 3’ X 10’ in order to assure space for the root zone. Where box style planting beds currently exist, the space shall be enlarged to the above dimensions. The rectilinear shape may be substituted with Forestry approval, but a minimum of 30 sq. ft. of root zone must still be observed.Trees require ample root space for optimum growth and longevity, so planting beds larger than the minimum are welcome and desirable where there is still sufficient space for pedestrian traffic.

12. QUALITY ASSURANCE

A. Source Quality Control

1. Ship landscape materials with certificates of inspection required by governing authorities. Comply with regulations applicable to landscape materials. 2. If specified landscape material is not available, proposed substitutions shall be discussed at the Pre-Construction Conference.

B. Tree Quality

Provide trees of quantity, size, genus, species and variety shown on plant list and/or drawings and scheduled for landscape work, complying with recommendations and requirements of ANSI Z60.1 "American Standard for Nursery Stock." Provide healthy, vigorous stock, grown in a recognized nursery and in accordance with good horticultural practice as per their standards, free of disease, insects, eggs, larvae, and defects such as knots, sun-scald, injuries, abrasions or disfigurement. Label at least one (1) tree of each variety with a securely attached waterproof tag bearing legible designation of botanical and common name.

1) There shall be no roots greater than 1/10 diameter of the trunk circling more than one-third the way around in the top half of the root ball. Roots larger than this may be cut provided they are smaller than one-third the trunk diameter. There shall be no kinked roots greater than 1/5 the trunk diameter. Roots larger than this can be cut provided they are less than one-third the trunk diameter.

2) Trees should be rooted into the root ball so that soil or media remains intact and trunk and root ball move as one when lifted, but not root bound. The trunk should bend when gently pushed and should not be loose so it pivots at or below soil line.

3) The point where the top-most root in the root ball emerges from the trunk shall be within two inches of the soil surface. It can be exposed and visible at the soil surface (see illustration lower left).

4) The relationship between caliper, height and root ball size shall meet the ANSI Z60.1 standard.

5) There should be one dominant leader to the top of the tree with the largest branches spaced at least 6 inches apart (see illustration top-left). There can be a double leader in the top 50% of the tree on a quality plant or in the top 10% of the tree on a plant of exceptional quality.

6) The tree canopy should be mostly symmetrical and free of large voids. Clear trunk should be no more than 40% of tree height unless otherwise specified in the planting specifications.

7) Branches should be less than 2/3 the trunk diameter (see illustration top right).

8) Trees greater than 1.5 inches caliper should be able to stand erect without a supporting stake.

9) Open trunk and branch wounds shall be less 10% of the circumference at the wound and no more than 2

inches tall. Properly made pruning cuts are not considered open trunk wounds. There should be no conks or bleeding, and there should be no signs of insects or disease on more than 5% of the tree.

10) If any of the above conditions are not met, trees may be rejected.

C. Inspection and Delivery of Trees

1. The City Forester reserves the right to pre-inspect nursery stock prior to shipping. The Contractor shall name nursery suppliers under Source of Supply, and inform the City Forester of proposed shipping dates once the contract is awarded. The City Forester may request digital pictures and dimensions of the stock, and shall determine the necessity of a pre-shipping visit to the nursery to confirm plant quality. The standards set out in B above shall be used as the guarantor of plant quality and health, as well as general specifications for the species. The City Forester will enforce the minimum grade standard.

Further, the City Forester shall inspect trees upon delivery prior to acceptance, and before planting, for compliance with requirements for genus, species, variety, size and quality. The City also retains the right to further inspect trees and shrubs for size and condition of balls and root systems, insects, injuries and latent defects, and to reject unsatisfactory or defective material at any time during progress of work. If trees are rejected, they must be immediately removed from project site.

2. Deliver trees after preparations for planting have been completed and install within six (6) hours of delivery. If planting is delayed more than six (6) hours after delivery, set planting materials in a protected area, protect from weather and mechanical damage, and keep roots moist (The City does not provide pumps or any other assistance in this endeavor). Do not prune before delivery. Protect bark, branches and root system from sunscald, drying, sweating, wind whipping and other handling and tying damage. Do not drop trees during delivery. C. PLANT STANDARDS 1. Broad or single upright trees: are healthy, vigorous trees that are well shaped, well branched, and well foliated (subject to natural growth of the variety).

• Trunk and Branches - 1) Single, straight trunk, medium, well formed and sturdy; 2) Lateral branching fairly plentiful with medium distribution; 3) Sprouts cleanly removed; and 4) Pruning scars clean cut leaving little or no protrusion from the trunk or branch.

• Foliage - 1) Tree fairly well supplied with healthy, vigorous leaves of normal size, shape, texture and deep green color according to the season or degree of dormancy; 2) Maximum chlorosis 10% of total foliage; and 3) Pest or mechanical destruction not to exceed approximately 1/4 of individual leaves nor affect more than 1/4 of the total foliage. Deterioration of foliage caused by seasonal change expected.

• Root System - 1) Shall be sturdily established; 2) Shall not be excessively root bound.

2. Trunk and Branches -

• Well formed and sturdy; • Good branching, uniformly distributed to form a well-balanced plant; • Pruning scars clean cut leaving little or no protrusion from trunk or

branch; • Graft union healed 75% or better; and • No extreme succulence.

3. Foliage -

• Well supplied with leaves of normal size, shape, color, and texture; • No holes, cavities, or depressed areas caused by broken or dead

foliage; • Maximum chlorosis is very slight and not more than 10% of total

foliage; and • Pest damage confined to no more than a few individual leaves.

4. Root System -

• Sturdily established; • Shall not be excessively root bound.

13. PLANTING OPERATIONS:

A. TREE LAYOUT: The XYZ COMMUNITY GROUP will give the Contractor the location of each tree to be planted prior to the planting operation.

B. TREE PITS:

1. The customary shape of pits shall be 3’ X 10’, or where it is

necessary to use irregularly shaped pits the surface shall be at least six (30) square feet.

2. As part of the planting operation, all soil in the pit measuring 2’ deep X 3’

wide X 10’ long shall be loosened prior to planting the tree.

a. Depth of tree pits shall be measured from finish grade.

C. BACKFILL: Depending on the type of tree and whether or not it is balled or bare-root, one of the following shall be used for backfilling the tree pit:

1. Balled Deciduous Trees - backfill with a mixture of 1 /3 humus and

2/3 topsoil by volume.

2. Balled Evergreen Trees - backfill with a mixture of 1 /4 humus and 3/4 topsoil by volume.

3. Bare-root Trees - backfill with a mixture of 1 /5 mushroom manure and 4/5 topsoil by volume.

D. TREE PLANTING: All trees shall be planted in pits as specified and shall be set at

such a level that, after settlement, they shall bear the same relation to the level of

the surrounding ground as they bore to the ground from which they were dug. The root ball shall be positioned in the planting hole so the finished grade of the landscape soil is even with or slightly lower than the point where the top-most root emerges from the trunk. If the top most root in the root ball is deeper than 1” inside the soil of the ball, remove soil so that this root is within the top 1”. DO NOT place soil over the top of the root ball.

1. Balled trees (B & B) shall be planted with the appropriate material specified

carefully tapped around and under the base of each ball to fill the voids. Prior to backfilling, remove all ropes, wires, cloth, etc., from the top 1 /3 of the ball. No cloth shall be completely removed or pulled out from under the ball. Care shall be taken to avoid the formation of air pockets around the ball when planting. Upon completion of backfilling operations, a saucer 2” high capable of holding water shall be formed around each tree using soil from the planting hole.

2. Bare-root Trees (B R) shall have all broken or frayed roots cleanly removed

prior to planting. Each tree shall be placed in the tree pit so that its roots are properly spread out and then the topsoil mixture specified carefully worked in among the

roots. Before backfilling, incorporate five (5) pounds of 6-10-4 fertilizer, as specified, with each cubic yard of topsoil mixture and mix by hand or rotary mixer. Topsoil mixture shall be thoroughly settled around roots by tamping and watering. Upon completion of backfilling, a saucer, as specified for balled trees, shall be formed.

3. All trees shall be treated at the time of planting and initial watering with the Mycorrhizal product specified.

4. All balled trees shall be treated at time of planting and initial watering with

the controlled release granular fertilizer specified.

5. All trees shall be mulched at time of planting with a minimum of two (2) inches of the shredded wood mulch material specified by the City Forester.

APPENDIX D:

Pilot Project Soil Test Results