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Oregon Planfor Salmon and Watersheds i

The Coos Watershed Association is a 501(c)(3) non-profit organization whose mission is “to provide a framework to coordinate and implement proven management pratices, and test promising new management practices, designed to support environmental integrity and economic stability for communities of the Coos watershed.” The Association, founded in 1994, works through a unanimous consensus process to support the goals of the Oregon Plan for Salmon and Watersheds. Our 21 member Board of Director includes representatives from agricultural, small woodland, waterfront industries, fisheries, aquaculture, local government, environmental organizations, industrial timberland managers, and state and Federal land managers.

Acknowledgements

The projects and monitoring efforts described in this report are the result of the contributions of many people. Our project partners include Chris Massingill, developed the riparian monitoring protocol, Mark Stueve, designed the riparian monitoring database, Mike Lester, Chuck Matayo, Richard Howard, and Bessie Joyce conducted the plant monitoring, Bruce Fallonsby, assisted with planting design, Jim Jaberg, Charles and Joan Mahaffy, Tom and Mindy Wilson, Jim and Bobbi Smith, volunteered the land and assisted in project implementation, John Colby, initiated many of these projects as Project Manger, Matthew Anderson and Jon Souder managed implementation and monitoring.

We wish to acknowledge our reviewers for this report, Chris Massingill and John Colby. Any remaining errors are our own. We have received support and encouragement from our grant program officers Mark Grenbemer of OWEB, Dan Perritt of the U.S. Fish & Wildlife Service, and Rachel Burr of the Oregon Department of Environmental Quality.

Funding Sources

This report has been funded by the United States Environmental Protection Agency under assistance agreement CO-000451-03 to the Oregon Department of Environmental Quality and U.S. Fish and Wildlife Service – Northwest Economic Adjustment Initiative grant (#1448-13420-01-J117). The contents of this document do not necessarily reflect the views and policies of theEnvironmental Protection Agency, nor does mention of trade names or commercial products constitute endorsement or recommendation for use. Monitoring of the projects was funded by theOregon Watershed Enhancement Board grants 99-113, 201-612B, and 204-372C and U.S. Fishand Wildlife Service – Northwest Economic Adjustment Initiative grant (#1448-13420-02-j213).

Suggested Citation:

Anderson, M. and J.Souder. 2005. Coos Watershed Association Riparian restoration planting and establishment monitoring report. November, 2005. Charleston, OR: Coos Watershed Association.

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Riparian Restoration Planting and Establishment Monitoring Report

Matthew C. AndersonJon A. Souder, Ph.D.

November 2005

Coos Watershed AssociationP.O. Box 5860

Charleston, OR 97420 (541) 888-5922 (Fax)

888-6111E-mail: [email protected]

Executive Summary

Because there has been a significant riparian planting effort on Oregon Coast streams, and since there has been poor tracking of the success of these projects, we have implemented a monitoring effort that will be able to help answer three critical questions to increase our understanding of riparian plantings 1) are we successfully stocking riparian forest buffers and meeting our stated goals at a program level, 2) how successful are the different implementation strategies that we have used to establish trees, and 3)what things are impacting our riparian plantings at a project level that we can react to and prevent future plant damage?

This report provides the preliminary results of the monitoring of riparian plants on restoration projects conducted by the Coos Watershed Association. These projects were monitored immediately following planting and annually after each growing season. At least 10% of the plants from each project were within the monitoring sample plots, and every plant within those plots received a tag in order to track the plant individually. During each monitoring period the growth and condition of each plant was recorded. A significant amount of the effort for the monitoring has been in the development of the protocol and the data management tools to make this dataset functional.

Based upon the monitoring data that was collected and analyzed, there is evidence to suggest that the monitoring protocol being used can detect differences in planting success based upon treatment methods. There is a high degree of difference in both plant survival and growth among the species that were planted and among the types of plants (conifer, hardwood, and shrub). In areas where banks were reshaped to increase bank stability, plants had similar survival but lower average growth compared with the plants in control areas, where no bank shaping occurred. Similarly, where weed mats were used, therewas no notable difference in survival, but both hardwoods and conifers had higher growth when grass competition was suppressed by weed mats during the first 3 growing seasons after planting.

Information from the first years of plant monitoring of CoosWA projects is encouraging. However, most of the planting projects are in the very early stages of development and have mortality each subsequent growing year. Although some of the trees are large enough that they are no longer threatened by competing brush, there are some long-term risks still to those plants, such as beaver and land management changes.

Introduction……………………………………………………………………………. 1Development of the Tools to Monitor Riparian Plantings…………………………….. 3

Database as data management and reporting tool……………………………… 6Database as analysis tool……………………………………………………….. 6Database stream lining of monitoring data collection and entry……………….. 6

Riparian Planting Summary…………………………………………………………… 6Evaluating Winter Springs Ranch Riparian Planting Project Status………………….. 10Evaluating the Effect of Bank Reshaping on Growth and Survival………...………… 12Evaluating the Effectiveness of Weed Mats…………………………………………... 15Program Overview…………………………………………………………………….. 16Conclusions and Recommendations…………………………………………………... 18

List of Figures

Figure 1. Intensive Riparian Monitoring Adaptive Management Flow Chart………... 4Figure 2. Riparian Silviculture Database Main Form…………………………………Figure 3. Map of CoosWA Riparian Restoration Projects in the Lower S.F. Coos

River and Millicoma River …………………………………………………

5

7Figure 4. Coos River Planting Plan…………………………………………………… 8Figure 5. Plant Survival by Species at the Winter Springs Ranch Project……………. 10Figure 6. Average Plant Height by Age at Winter Springs Ranch Project…………… 11Figure 7. Plant Survival in Reshaped and Control Planting Zones…………………… 13Figure 8. Average Plant Growth on Reshaped and Control Planting Zones………….. 14

Zones………………………………………………………………………... 14Figure 10. Survival of Three Species With and Without Weed Mats………………… 15Figure 11. Average Growth of Three Tree Species With and Without Weed Mats….. 16Figure 12. Current Plant Survival on Monitored CoosWA Projects………………….. 17Figure 13. Average Plant Growth by Species Based on Monitored CoosWA Plants… 17

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Table of Contents

Figure 9. Average Levels of Brush Competition in Reshaped and Control Planting

List of Photos

Photo A. Pre-project condition, blackberry and reed canary grass are the dominange vegetation at the site………………………………………………………… 12

Photo B. River bank is visible after vegetation has been cleared…………………….. 12Photo C. River bank after reshaping………………………………………………….. 12Photo D. Riparian conditions in 2005………………………………………………… 12Photo E. A Sitka spruce sapling protected from reed canary grass by a 3’x3’ weed

mat…………………………………………………………………………... 15

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Coos Watershed Association Riparian Planting and Establishment Monitoring

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Introduction

Starting in 2002, the Coos Watershed Association (CoosWA) began a new suite of riparian planting projects which involved more detailed planting prescriptions, intensive site preparation, testing of new planting methods, and increased maintenance compared with past projects. The planting effort has included over 50,000 plants at 7 riparian restoration project sites between 2002 and 2005. Along with this revised planting strategy, the CoosWA implemented a riparian monitoring protocol in order to test riparian plant establishment techniques. The monitoring protocol was developed as part of the Coastal Oregon Riparian Silviculture Guide (Massingill, 2003) through an iterative process with numerous watershed restoration groups along the coast of Oregon that ran trial data collection efforts to refine the monitoring protocol.

The long-term goals of these riparian restoration projects include stream bank stabilization, stream temperatures reduction, increase in allocthonus inputs to the stream, and future large wood recruitment to the stream. Although the functions of healthy riparian areas are fairly well-established in the literature, there is little evidence that these goals can be achieved through riparian planting projects. For the projects included in this report, baseline data and early post-project monitoring has been collected; however, dueto the short time lapse between project implementation and realizing these goals, the effectiveness monitoring that has been conducted on these sites is highly inconclusive at this time. All of the common long-term goals or riparian projects rely on the successful establishment of the riparian plantings, and it has been the experience of the CoosWA that significant effort and careful implementation are required for successful establishment in the riparian areas of the streams of coastal Oregon. Recognizing the need to improve the planting techniques, this report will address the ways in which riparian monitoring can be implemented to improve establishment techniques.

In order to the monitor riparian establishment, the CoosWA worked primarily with the Riparian Silviculture Guide’s intensive monitoring protocol. The intensive monitoring entails establishing random sample plots that encompass a subset of at least 10% of the project plantings. Each plant within these plots were monitored at the time of planting and each fall afterward. The goal of this report is to 1) discuss the development and the application of the intensive riparian monitoring program, 2) use the monitoring data to compare plant establishment techniques by comparing the growth and survival of treatment and control samples, 3) detail the riparian restoration program of the CoosWA, and 4) identify lessons learned and future directions for monitoring.

Although reforestation has a long and rich history on the coast of Oregon, riparian reforestation in lowland, broad valleys has become widespread only more recently. Both the goals and the challenges of riparian tree establishment are significantly different from the well-refined field of upland tree planting. Instead of having direct economic gain, riparian restoration goals usually include fish and wildlife habitat improvement or soil conservation. Due to the difference in goals and in planting conditions, the selection of plant species is often entirely different from traditional forestry. The rehabilitation


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projects evaluated in this report have planted 8 to 12 species including conifers, hardwoods, and shrubs. Many of these species have been considered pests to the forestry profession, and therefore have little information available about their specific needs to become established or “free to grow.”

Between 1997 and 2003, $6.9 million was spent on riparian restoration on the Oregon Coast (Oregon Plan 2003-2005 Biennial Report Vol II). The success of these efforts has been poorly documented—even at the project level in many cases—and poorly reported.A review of Oregon coast range planting projects showed that many projects in the region had very low survival (Anderson and Graziano, 2002). However, Bishaw et al (2002) detailed a trial red alder riparian establishment project on Coast Range agricultural lands and made a strong case for the use of tree protection in order to establish riparian trees. Due to the uncertainty of the riparian reforestation success and the relative paucity ofcase studies, it is important to document this process and test the current practices.

Riparian restoration methods are highly variable depending upon the eco-region, the location in the watershed, and the specific site characteristics of the restoration project. On the Oregon Coast, allowing natural regeneration to restore the site is rarely successful due to the rampant and highly competitive nature of invasive riparian plant species. Specifically, Himalayan blackberry, Japanese knotweed, and field bindweed are usually much faster at pioneering disturbed sites in agricultural bottomlands, and each of these species can put on 12 to 15 feet of vertical growth per year. Under such conditions,restoration of riparian areas usually involves very specific planting techniques and a well- coordinated post-planting maintenance regime.

Working in the riparian zone has numerous other challenges. Herbivory from riparian animal species—such as beaver, nutria, and voles—can devastate a planting project. Natural processes including flooding and channel migration can work against the rehabilitation of native plants. Water table interactions with planted species can also make or break a planting project. Soil characteristics and nutrient availability also affect planting success. To add to this complexity, each of the different species responds differently to these processes and conditions. For example, a flood that pushes over a Sitka spruce is likely to kill the plant, but a black cottonwood that is pushed over is likely to sprout adventitiously and multiply.

Intensive riparian monitoring is useful to inform adaptive management, testg species performance in different planting conditions, and test planting techniques. Adaptive management that reacts to the changing conditions of a project through the on-going analysis of conditions is one of the more immediate values of the monitoring. For example, through monitoring we discovered that rodent girdling was causing damage to a large portion of the plants and we were able to react by adding foil to the plant stems which largely eliminated the problem. Other examples of examining speciesperformance under various conditions and planting techniques will be examined in more detail below.


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The Oregon Coast Riparian Silviculture Guide was a helpful assimilation of existing knowledge on riparian establishment techniques; however, much of the information was based on experiential and anecdotal evidence. It is important to experimentally test the effectiveness of various planting practices. Sweeney et al. (2002) were able to identify a significant difference in survivorship of bottomland hardwoods in Maryland between plants that were treated with tree-shelters for protection from herbivory and weed mats or herbicide applications. Establishing the effectiveness of restoration methods within the Oregon Coast eco-regions will only be possible with the intensive monitoring protocol.

Tree “yield” curves and equations have been developed for many commercially important trees species (Harrington and Curtis, 1986), but equivalent information for riparian species has not been previously addressed. Such curves are potentially avaluable tool for restoration managers. Knowing the number of years a plant species will need release from competing vegetation before reaching a free-to-grow height would improve budgeting of restoration costs. Also, knowing the long-term expected growth rates of riparian species can assist the modeling of potential site benefits over time.

Development of the Tools to Monitor Riparian Plantings

The development of the current riparian monitoring protocol was one element of the process to synthesize and publish current available knowledge on riparian planting methods on the coast of Oregon. The Coastal Riparian Silviculture Guide, which details the protocol for the riparian monitoring was funded by a grant from the OregonWatershed Enhancement Board to the CoosWA. Chris Massingill worked with numerous Oregon coast watershed councils to trial the monitoring protocol before it was published by the CoosWA in 2003.

The Coastal Oregon Riparian Silviculture Guide details two monitoring strategies: 1) the intensive method, which involves setting up sample plots within a project site, individually numbering plants and collecting information about the site conditions andthe plant status; and 2) the extensive method, which is a reach based survey of the status of a project, intended primarily for existing projects that need to be assessed for current conditions.

Riparian establishment monitoring is a long-term process that begins before the restoration project is implemented. Information about the project site, goals, photos, and site preparation are stored on the Planting Project Summary Form. Specific information about the planting techniques are recorded in the Planting and Establishment Record including the number of each species planted, stock age, source and method of planting and general notes about conditions at the time of planting. Collecting this information in a uniform way over time and across multiple projects is essential in managing a riparian restoration program. Storing the information in a single place allows for improved management and the ability to analyze the status of the plantings and evaluate the methods used.


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Figure 1 – Intensive Riparian Monitoring Adaptive Management Flow Chart.

Monitoring sample plots are set up on 10% of the area in each of these projects. The plantings are long and narrow stream-side buffers, so plots covering 10% of the planting length are established at forced intervals along the stream. The starting point for the first plot is established by generating a random number from the Microsoft Excel random number generator between 1 and the number of feet between plots. A fencing t-post is placed in the center of each plot. The plot dimensions are laid out with tape and aluminum tags are used to mark each plant in the sample plot area.


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Soon after planting, spring establishment monitoring is conducted to gather baseline information on each plant including height, competition, damage, land form, slope, and method of tree protection. The plantings within the sample plots are monitored each subsequent fall and each tagged plant is resurveyed for height, live-crown height, overstory, brush, and grass competition, damage to the plant and the source of the damage (beaver, flooding, etc), and continuing function of tree protection. These subsequent surveys allow the monitoring of changing conditions at the planting site.

Because of the numerous data fields collected on a site between the Planting Project Summary Form, the Planting and Establishment Record and the Monitoring Forms, we determined that a database would be essential for long term data storage, organization and analysis. The use of a database allows the synthesis of data from numerous projects which will improve the statistical significance of the data analysis.

Figure 2 – Riparian Silviculture Database Main Form

The Riparian Silviculture Database has numerous features to assist riparian project management and monitoring:

Easy user interface for entering project information including live-links to maps and photos.Pre-built pivot charts and exportable pivot tables that calculate plant heights. Data from multiple projects that can be queried and sorted by the field of your choice (e.g. species, age, or treatment type).Tables of plant species, protection methods, and damage sources that can be modified in order to customize the database for local riparian planting conditions.


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Database as data management and reporting tool -Having all of the information about a planting project managed in a single location is extremely valuable for general management and reporting. Information about the number of trees planted, miles of stream treated, and overall plant survival and growth are readily available. The database is also designed to store project goals, site-preparation treatments, plant protection methods, and maintenance records. Project effectiveness monitoring is listed, although the database does not manage collected project monitoring data.

Database as analysis tool – One of the primary strengths of the database is the ability to analyze planting methods across a planting site and among different sites. In many cases it is necessary to set up the plantings as an experiment with treatment and control populations, but it is also possible with the numerous data fields collected to test hypotheses formulated from field observations.

Database streamlining of monitoring data collection and entry - With the development of the database, we have been able to streamline the monitoring data collection and entry improving efficiency and quality control. During the spring establishment data collection, all monitoring parameters are collected. These include: Tag#, species, height, live crown height, landform, slope, overstory, brush and grass competition, plant status, tree protection, damage, maintenance required, and general comments. A standardized report creates the forms for subsequent monitoring cycles with the values of the fields that will not change between monitoring visits pre-entered and the data fields left blank wheredata needs to be collected while monitoring. The report also eliminates trees that are dead so the person collecting data knows not to spend time looking for that plant.

Riparian Planting Summary

The CoosWA implemented 7 riparian restoration projects between 2002 and 2005 on the South Fork Coos River and tributaries, Millicoma River and tributaries and Palouse Creek (see figure 3). These projects involve replanting of riparian zones that have been cleared for agricultural purposes, specifically grazing and hay production. In the Coos River basin, most of the bottomlands have been grazed for over a century. Some of the results of the agricultural uses include compacted soils on high floodplain terraces, eroding stream banks due to vegetation removal, and elevated stream temperatures from loss of shade-casting vegetation.

P


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Figure 3 – Map of CoosWA Riparian Restoration Projects in the Lower S.F. Coos River and Millicoma River.

Hendrickson CreekPackard Creek

Winter Springs Ranch

Fern Hollow FarmsRogers Creek

Wilson Ranch

Fern Hollow FarmsS.F. Coos River

N

0.5 0 0.5 1 Miles

Plant lists were developed from the South Coos Watershed Analysis (BLM, 1999) which mapped the 1857/1871 vegetation composition based on Government Land Office cadastral survey notes. Species common to the Coos River bottomlands included conifer and myrtle trees on the high terraces and Sitka spruce and hardwoods, such as big-leaf maple, ash and crabapple, in the poorly drained low terraces. Black cottonwood and shrubs that are known to exist in the area were added to the planting to further increase the riparian diversity and wildlife benefits of the projects.

Table 1. Location, extent, and implementation date of CoosWA riparian restoration projects

Project StreamPlanting

Area (Ac.)# of

plantsPlanting

YearWinter SpringsRanch Coos River 8 12,332 2002-2003

Wilson RanchCoos River, RogersCreek 12 13,200 2003-2004

Mahaffy Ranch Packard Creek 2 3,846 2003Mahaffy Ranch Hendrickson Creek 1.5 5,497 2003ODF Ranch Palouse Creek 3.5 5,221 2003-2004Fern Hollow Farms Coos River 5 3,960 2004Fern Hollow Farms Rogers Creek 7 6,850 2004Total 39 50,906


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The planting projects treated three different types of riparian areas, each area requiring a different planting plan. Approximately 2.5 miles of the Coos River Mainstem, which has an average channel width of 80 feet was planted in 60- to 100-foot buffers. The Riverhas high banks with some narrow low terraces. The planting plan for the Coos River generally followed the diagram below (Figure 3), developed by Bruce Follansbee; however, Sitka spruce, Oregon ash, and black cottonwood were planted lower on thebank in some cases. Smaller streams, 5- to 20-foot bankfull width, were planted with 15- to 50-foot buffers. These streams generally have a single floodplain terrace and the connectivity of the floodplain varies by site. A similar mix of species was planted on these smaller streams, but the planting zones were less distinct. The final type of riparian area treated was wetlands connected to pasture drainage ditches. These areas have relatively small drainage areas, but they have poorly drained soils that are inundated regularly in the winter and stay moist through the summer. In these areas, the plantings consisted of willow, crabapple, Oregon ash, and Sitka spruce.

Figure 4 – Coos River Planting PlanCoos River Planting Plan

Because all of the planting sites were almost completely invaded by noxious weeds, intensive site preparation methods were required. On most blackberry dominated sites, the brush was treated with a glyphosate-based herbicide used in the fall before planting. Early in the winter, a excavator mounted brushmower was used to mulch the blackberry canes. During this process, every attempt was made to save existing native vegetation, which usually consisted of willow, elderberry and alder. Where plants were located in heavy pasture grass or reed canary grass, a 4 square foot patch of grass was scalped with a hoe to reduce early grass competition. In one project area, the high banks of the Coos River were too steep for planting so an excavator was used to reshape or pull-back the


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bank before planting. For this project, monitoring plots were established in reshaped and control areas to test possible impacts of this site-prep action (see page 12).

Planting was executed between January and March. The stock type varied between species and years, but almost all plants were bare root stock that ranged from 1-0 to 2-1 age classes except for willow, red-osier dogwood and some cottonwood which were locally harvested live stake cuttings. Whenever possible, we obtained plants from southern Oregon or northern California coastal seed zones. Plants were covered during transportation and stored in a temperature regulated tree cooler until they could be planted. Bare-root plants were shovel-planted, as opposed to hoe-dad planted, due to the high compaction of soils from livestock grazing. Live-stake plants were planted withplanting bars that were used to pilot a hole and then pushed into the ground at least 2 feet.

The tree protection methods of these projects varied by species and by planting location. The three types of tree protection utilized were 1) tree tubes, to minimize browse damage from ungulates and to deter beaver and voles, 2) weed mats, used in areas of heavy grass competition to reduce the risk of lodging and increase moisture conservation, and 3) aluminum foil wrapped around the base of the plant to help prevent rodent girdling. Tree tubes and weed mats were applied to some plants and not applied to others so that the efficacy of the protection method could be tested against a control group.

A significant portion of the effort for these planting projects has been spent on post- planting maintenance. The plantings have been physically cleared of blackberries once each year during the summer to release the plants during the growing period. The clearing has been completed by CoosWA staff and Shutter’s Creek inmate work crews with weed-eaters and hand tools. Due to the vigorous growth of blackberries, even annual clearing often does not entirely remove the competition pressure from the plantings. In some cases the trees could not be found to be monitored due to extreme blackberry growth and the tree status was marked as unknown.

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Evaluating Winter Springs Ranch Riparian PlantingProject Status

For the purposes of evaluating and managing the status of a planting, plant survival and plant growth are utilized as performance criteria. Plant survival measurements can help predict how well stocking density goals are being reached. Current tree heights are valuable for analyzing the ability of the planted species to compete with other vegetation at the site.

Figure 5. Plant Survival by Species at the Winter Springs Ranch Project

100%

90%

80%

70%

60%

50%UnknownLive

40%

30%

20%

10%

0%0 1 2 3 0 1 2 3 0 1 2 3 0 1 2 3 0 1 2 3 0 1 2 3 0 1 2 3 0 1 2 3 0 1 2 3 0 1 2 3 0 1 2 3

grand fir western western sitka black big leaf Oregon pacific red red-osier vinered cedar hemlock spruce cottonwood maple ash ninebark elderberry (creek)

dogwoodmaple

Figure 5 above shows the percentage of individuals of each plant species at the Winter Springs Ranch that are alive or unknown at the time of each monitoring cycle. As well as allowing managers to evaluate the site stocking level, one can quickly identify which species are doing well and which are not. For instance, western hemlock and red elderberry are exhibiting low survivorship at the Winter Springs Ranch planting project. In general, hemlock is not a pioneer species that would be found in this early level of succession, which may be contributing to the low survivorship of these plants. Red elderberry, which was one of the existing remnant native plant species in this riparianarea before the planting project, may be more difficult to propagate with the methods that are being used. This level of analysis does not allow for identification of the factors that are contributing to or limiting survival, but it provides a useful overview of the performance of the different species.

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Figure 6. Average Plant Height by Age at Winter Springs Ranch Project

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Figure 6 gives another useful overview of the status of the planting. Having growth curves for the different riparian species is important where there is intense competing vegetation. Because the first goal of plant establishment is getting plants to grow to a height that they are ‘free-to-grow,’ or able to compete with other vegetation, it is important to track the plant height for planning and budgeting maintenance. On a broader level, by tracking numerous individuals of a certain species over time at many different locations, it will be possible to calibrate growth curves for improved restoration planning. Plant growth curves can inform predictions of the number of years needed to shade a given channel reach based on different planting strategies and prescriptions.

The results from the Winter Springs Ranch project suggest that after three years of growth, conifer species are 3-5 feet tall, the hardwoods range from 5- to 14-feet tall, and the shrubs are still in the 1-3 feet average height range. Because the growth will vary greatly under different conditions, the more individuals and the more sites that are included in the growth curve information, the better sense one can have of the expected performance of the species.


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Evaluating the Effect of Bank Reshaping on Growth andSurvival

Physically reshaping banks has been a common practice in riparian restoration projects, especially those on larger stream systems that have steep and eroding banks. Pulling back banks can increase the structural stability of the banks by decreasing the angle of repose. Also, reshaping increases the amount of surface area near the stream interface that can be planted with deep-rooting, woody vegetation.

The process of reshaping the banks usually includes removing, or at least adjusting a significant amount of riparian soils. Top-soil layers are either spread thinly on a high terrace or end-hauled from the site entirely. Bank re-shaping was implemented at the Winter Springs Ranch Project and sampling plots were established to compare the planting success in areas that were re-contoured and those that were not disturbed.

Winter Springs Ranch Bank Reshaping and Planting: A) Pre-project condition,blackberry and reed canary grass are the dominant vegetation at the site B) River banks visable after vegetation has been cleared C) River bank after reshaping D) Riparian condition in 2005.

A. B.

C. D.

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Figure 7. Plant Survival in Reshaped and Control Planting Zones.

100

90

Unknown80 Live

70

60

50

40

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01 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4

TreatmentConifers

ControlConifer

TreatmentHardwoods

ControlHardwood

TreatmentShrubs

Control Shrub TreatmentTotal

Control Total

In Figure 7, plant survival is compared between plots that are in locations where the banks were reshaped and those that were not. There does not appear to be a notable difference in the survival of conifers or hardwoods, but the reshaped areas appear to have a higher shrub survival. On the other hand, the areas that were not reshaped had higher average plant growth for conifers, hardwoods and shrubs (see Figure 8). This could be related to the disturbance and removal of organic soils in the Treated areas.

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Figure 8. Average Plant Growth on Reshaped and Control Planting Zones

10.00

9.00

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Age 0Age 1Age 2Age 3Age 4

7.00

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4.00

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2.00

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Treatment conifers Control conifers Treatment hardwoods

Control hardwoods Treatment shrubs Control shrubs

Figure 9. Average Levels of Brush Competition in Reshaped and Control Planting Zones

1.8

1.61.4

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10.8

0.6

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Treatment

Control

BrushLevel

Description

0 No brush shading or brushwithin 2 feet

1 Brush shading plant <25%2 Brush shading plant 26-50%3 Brush shading plant >50%

0 1 2 3 4

Planting Age

As displayed in Figure 9, brush competition levels are notably different in the reshaped and control planting zones. Although brush, primarily Himalayan blackberry, had an earlier presence in the reshaped areas, the level of competition in the control areas was much higher in year 2 through 4. This provides more evidence that the disturbance of soils in the reshaped areas could be limiting the growth of riparian vegetation whether native or invasive. Also, the removal of the blackberry rootstock could be effecting the brush competition levels.

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Evaluating the Effectiveness of Weed Mats

An important decision for riparian site planners is the type of plant protection that will be used in a planting project. There is usually a site-specific evaluation for the need of plant protection; however, it is valuable to know how effective the treatment is in order to justify the added expense of the additional treatment cost. Although most plantprotection methods are designed to reduce animal damage, in some cases, we have used3’x 3’ weed mats to protect the plants from grass competition. Establishing native trees and shrubs in reed canary grass has proven especially difficult, and pasture grasses can prevent establishment of young seedlings.

Photo E. A Sitka spruce sapling protected from reed canary grass by a 3’x3’ weed mat.

Figure 10. Survival of Three Species With and Without Weed Mats.100%

90%

80%

70%

60%

50%Status UnknownLive Plants

40%

30%

20%

10%

0%0 1 2 0 1 2 0 1 2 0 1 2 0 1 2 0 1 2

Treated Oregon ash Control Oregon

ashTreated western

red cedarControl western

red cedarTreated Sitka

spruceControl Sitka

spruce

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Figure 11. Average Growth of Three Tree Species With and Without Weed Mats.

6Age 0

Age 1

Age 25

4

3

2

1

0Treated (23) Control (48) Treated (40) Control (66) Treated (33) Control (58)

Oregon ash western red cedar sitka spruce

Figures 10 and 11 above compares the survival and growth of plants that received weed mats versus those without weed mats for Oregon ash, western red cedar, and Sitka spruce at the Wilson Ranch Riparian planting site. There is very little difference in the plant survival of these three species, and the Oregon ash survival is actually lower for the individuals treated with weed mats. The detectable difference is in the plant growth ofthe western red cedar and the Sitka spruce. Both of the conifer species averaged almost one foot of extra growth over the first two years when treated with weed mats. These results of the value of weed mats are somewhat inconclusive and will require more monitoring and statistical validation.

Program Overview

Having updates on the plant survival and growth at each of the project sites allows us to manage the replanting and maintenance intensity on the projects. In Figure 12 below, the plant survival is shown for each of the projects. It is important to note, however, that the projects were not planted in the same year. The Winter Springs Ranch, which has the lowest survival, has been through 3 to 4 growing seasons, and many of the trees are taller than the competing vegetation. For the first years after monitoring, some mortality every year has been common among all of the projects. We expect that the plants that reach a certain age and height will be less susceptible to mortality over time and project survival will level off.

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Figure 12. Current Plant Survival on Monitored CoosWA Projects.

Current Plant Survival on CoosWA Projects

100%

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50%UnknownLive

40%

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0%Palouse Creek Wilson Ranch Packard Creek Hendrickson Creek Winter Springs Ranch

Figure 13. Average Plant Growth by Species Based on Monitored CoosWA Plants.

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Figure 13 shows the average height of the plants that have been propagated in the CoosWA projects. In some cases, age 3 trees have a higher average height than age 4 plants. This is because there are more age 3 trees, and they have been more successful than the first season of planting. Over time, there will be enough records to have a strong sense of what can be expected from a plant species. It is important to remember that the plant heights detailed here are averages and that a plants will perform differently basedon local site conditions.

Conclusions and Recommendations

The development of monitoring protocols and tools to collect, manage, and analyze data in a consistent way over time and at different sites creates the ability to assimilate a large body of riparian planting information which can contribute significantly to the field of riparian restoration. The monitoring protocol creates an excellent foundation for turning riparian planting projects into horticultural experiments. With the information that has been collected, there are many more variables that can still be tested.

Given the analysis of three years of data collected at the Winter Springs Ranch, it is clear that plant growth and survival vary significantly by species. Hardwoods generally had the highest average growth and black cottonwood specifically out-competed all other species planted. Survival of cottonwood and ash trees was relatively high (70% or greater), but big-leaf maple did not have such high survival (~50%). Of the conifers monitored, Sitka spruce, western red cedar, and grand fir each had 60-75% survival ratesand put on an average of 2-3 feet of growth, but the western hemlock had very low (23%)survival and put on less than 1 foot of growth on average. After three years of monitoring, the shrub species Pacific ninebark and red-osier dogwood both had relatively high survival (~60-70%). Red elderberry and vine maple had lower survival and were difficult to find given the brush competition at the site. Further monitoring of shrub species plantings will be important to understand the appropriate establishmenttechniques for these speices.

Based upon the first attempt to analyze the effectiveness of riparian planting practices with the monitoring protocol, there is some evidence to suggest that the use of weed mats in areas of heavy grass competition may have a positive influence on growth in the first three years after planting. Also, plant growth may be negatively impacted by the disturbance created by reshaping steep, eroding stream banks. At this point, the analysis on the effective of planting practices only includes direct comparison of mean values of treatment and control populations. The outputs in this report need to be tested for statistical significance in order improve the analysis.

Collecting information on soil types and soil condition will also add an important element to the plant monitoring. Based on the first few years of data collection, we have seen vastly different growth performance of species at different sites. This may be largely influenced by soil conditions. Soil tests will also be important in the development of tree growth curves. Soil composition and compaction are both important variables in areas that have been historically used for livestock grazing.


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Another valuable change to the monitoring protocol would be a closer tracking of the maintenance that is performed. The current maintenance record includes method and timing of effort but not intensity or location to the plot level. Because brush maintenance is such an important element of establishing these riparian plantings, tracking the effectiveness and cost of physical and chemical treatments and methods would provide valuable information for future riparian efforts.

It will be important to continue to monitor plants into the future, even beyond the ‘free- to-grow’ height. There are a number of on-going risks that can impact a planting project after many years of growth. Most planting projects will not have the desired benefits for stream health for many years after planting. With this in mind, it will be important to find ways to keep trees tagged over the years and to periodically monitor these plants through the life of the planting project.


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Literature Cited

Anderson, M. and G. Graziano. 2002. “Statewide survey of Oregon Watershed Enhancement Board riparian and stream enhancement projects.” Salem, OR: Oregon Watershed Enhancement Board.

Bishaw, B., W.Emmingham, and W. Rogers. 2002. “Riparian forest buffers on agricultural lands in the Oregon Coast Range: Beaver Creek riparian project as a case study.” Research Contribution. Corvallis, OR: Oregon State University, Forest Research Laboratory.

Bureau of Land Management (BLM). 2001. South Fork Coos River Watershed Analysis.Version 1.2. North Bend, OR: USDI-BLM, Coos Bay District, Umpqua ResourceArea).

Harrington, C.A, and R.O.Curtis. 1986. ”Height growth and site index curves for red alder” Research Paper. PNW-358. Corvallis, OR: USDA Pacific Northwest Research Station.

Massingill, C. 2003. Coastal Oregon Riparian Silviculture Guide. Charleston, Oregon; Coos Watershed Association.

Oregon Watershed Enhancement Board. 2005. 2003-2005 Oregon Plan Biennial Report, Volume 2. Salem,OR.

Sweeney, B, S. J.Czapka, T.Yerkes. 2002. “Riparian forest restoration: increasing success by reducing plant competition and herbivory” Restoration Ecology 10(2):392-400.

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