For National Grid’s residential customers in New York

Trees and Your Electric ServiceManaging Vegetation to Ensure Electric Service Reliability

Trees and Electric ReliabiltyNational Grid serves over 1.6 millioncustomers along 36,000 miles of elec-tric distribution lines in New York thatdeliver the power you need and relyupon. Trees are an integral part of ourlife. We estimate that our lines areexposed to over 12 million trees, andinevitably, the conflicts between treesand overhead electric lines that developmust be addressed to assure yoursafety and service reliability. Trees canhelp you save energy when properlylocated, but are also a leading causeof electric service interruptions by con-tacting and damaging our overheadelectric facilities.

National Grid’s Tree Pruning ProgramNational Grid shares your concern andappreciation for trees. We recognizetheir value to you and your community.Diseased or damaged trees, thosewith structural defects, poor perform-ing species and those growing in thewrong place frequently cause poweroutages when they contact our over-head electric lines. Our vegetationmanagement program addresses treesalong selected distribution feeder cir-cuits typically on a five- to seven-yearcycle. Our professional utility arboristsperiodically review these feeders andadjust our schedules to keep trees asafe distance away. Since 2000,

National Grid is proud to have repeat-edly earned national recognition for itstree pruning programs. The NationalArbor Day Foundation has recognizedNational Grid as a “Tree Line USA”utility, through its demonstration ofexcellence in tree care, annual workertraining and a commitment to publiceducation and community tree planting.We are among a select few utilities toearn this prestigious national honor.

Utility PruningThe technique of “directional pruning”is most commonly used to attempt to naturally direct trees growth awayfrom the wires. This science basedpruning practice was developed inconjunction with the U.S. ForestService and is endorsed by theInternational Society of Arboriculture,the National Arbor Day Foundationand other tree care professionalsaround the world.

Our specifications are to maintain at least 10 feet of clearances from the primary lines next to, above andbelow the primary conductors in resi-dential, urban and maintained areasand at least 15 feet of clearance nextto, above and below the primaries inrural and unmaintained areas, whilesecondary electric lines require at least18 inches of clearance on all sides. Inorder to properly conform to industryANSI A300 pruning standards, it may

be necessary to cut limbs beyond the distance specified to the correctpoints of limb attachment within thecrown of the tree. Trees may initiallylook different following directionalpruning, but this line clearance pruningpractice allows trees to remain healthy.Additionally, in rural and unmaintainedurban areas under or immediatelyadjacent to our lines, we will cut small,volunteer or intrusive trees and tallgrowing brush to prevent future vege-tation encroachment. Damaged, poorlystructured trees or weak tree speciesmay require additional pruning or evenremoval. Stump treatments with Stateand federally approved herbicides maybe applied (when and where appropri-ate) to prevent the regeneration ofundesirable species, thus helping toreduce costs and repetitive work in the future.

The Benefits of DirectionalPruningDirectional pruning considers the natu-ral structure of the tree to reduce thenumber of cuts required. While thesize of the cuts in the work area mayseem larger than was common in thepast, fewer cuts mean better woundisolation and ‘healing’ for the tree.

The guiding principle of directionalpruning is the “90-3-90” rule. Typically,90 percent of the interfering branchescan be removed by making three larger

T h i s i s a n i m p o r t a n t n o t i c e . P l e a s e h a v e i t t r a n s l a t e d .

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cuts within the tree crown 90 per-cent of the time. We work with thenatural form of the individual tree as to where best to make our cuts,rather than simply shorteningbranches. ‘Round-overs’ of the treecrown are no longer acceptable orpracticed.

Proper CutsCrews will use the ‘collar cutting’method to remove limbs. Properlyplaced cuts facilitate more rapidwound closure as the tree is betterable to isolate the pruning cut.Research has found wound dressingsto be ineffective and they are nolonger applied.

Service Lines to Your Homeor BusinessNational Grid will remove limbs thatare pressing on the service line toyour property only at the time weperform cycle pruning of the feedersin your neighborhood, and we willassess the need for any additionalclearance pruning of your servicewire at that time. If you have a tree-line concern or question, please notifyour customer service center at 1-800-642-4272. Upon notice, wewill send a qualified representative

to investigate safety concernscaused by trees near our primarylines and report on our assessmentat the time of inspection.

Clean Up and Wood DisposalCrews will chip the branches theyremove from trees in your yard aspart of our cycle pruning programand rake the work area to pick upsmaller twigs/debris and dispersesawdust. Pieces of wood that cannot be chipped will be cut into manageable lengths and left nearthe base of the tree. In off-road and“unmanaged” areas, wood andbrush will be left ‘windrowed’ alongthe edge of the right-of-way to natu-rally decompose and provide shelterbenefits for wildlife. Paths, drainageditches and stream channels withinthe work area will be kept clear.

Tree Removals Near Primary LinesIn an effort to improve and maintainservice reliability, we periodicallyinspect critical portions of our pri-mary lines supplying your neighbor-hood to target ‘at risk’ trees thathave a high probability of failure.These “hazard trees” that are con-sidered for removal or additionalpruning are typically beyond theedges of the areas we normallymaintain. Not all trees require immedi-ate attention, nor can all trees realis-tically be removed. We focus ourefforts on the tree species and/ordefects most likely to cause an out-age in the most sensitive, criticalportions of the distribution circuit.

Tree Removals Near Service LinesNational Grid does NOT perform treeremovals for customer service lines.New York state law requires that alltree work in the proximity of over-head electric facilities be completedby individuals trained to recognizethe hazards of working near ener-gized lines. Should you need to havetree work completed on your propertynear overhead electric lines, ask your

arborist if their employees receivesuch training. If not, National Gridmay provide the necessary servicesand, by law, can charge you and/oryour contractor for the service provided.

Other Tree Related ServicesIn emergency or storm situations,National Grid is responsible for ONLYclearing damaged trees and limbsfrom our electric lines and facilities in order to restore customer service,allow reasonable access for emer-gency restoration crews or to ensurefuture service reliability. The cleanupof generated storm debris remainsthe responsibility of the tree owner,whether public or private.

Who Does the Pruning?Either National Grid's forestrydepartment and/or approved, utilitytree contractors will be used to com-plete the work, conforming to thesame nationally recognized industryANSI-A300 pruning standards, safetypractices and quality.

Your Safety Service reliability is notour only concern. Our vegetationmanagement program strives to pro-vide as much clearance as possiblebetween trees and energized over-head lines for safety reasons, too.Open, visible lines help to protectour workers, customers and privatecontractors working near these linesby avoiding accidental contact. Youcan further safeguard yourself andyour family by:

Allowing our tree crews to com-plete their work to meet our clear-ance specificationsNever operating tools or equipmentwithin 10 feet of overhead linesNever allowing children to climb trees near overhead linesNever building a tree house in treesthat are under or near power linesAlways being sure to “look upbefore you go up” and always call“Dig Safely New York” at 1-800-962-7962 before you plant a treeor dig on your property.

Not planting large-growing trees under or near overhead lines…and please don’t plant trees or shrubs near underground electric distribu-tion equipment boxes on your property.

For Your Future ProtectionNational Grid is active at the local andstate level in educating communities,professionals and individuals in selectingthe “right tree for the right place”.Failure to select and plant the appropri-ate species and to provide adequategrowing space from overhead electriclines eventually leads to the need forunwanted tree pruning or removals.

Tall-growing trees planted too close to homes, buildings and power linesfrequently leads to property damageand electric service outages duringheavy snow, ice and severe wind storms.

For more information about selectingand planting the right tree near powerlines, please call our Customer ServiceCenter at 1-800-642-4272 or visit the“Safety” section of our website atwww.nationalgridus.com to down-load a list of appropriate trees to plant (“How To Avoid Tree and UtilityConflicts”).

Thank you for Your Help and UnderstandingNational Grid appreciates your under-standing and cooperation. Together we can work towards reliable electricservice and still enjoy the beauty, benefits and value of trees.

Through Pruning

Side Pruning

Under Pruning

The following illustrations provide examples of the proper directionalpruning for shade and ornamental trees.

10’ +/- 10’ +/-

10’ +/-

10’ - 15’ +/-

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National Grid is an international energy

delivery company. In the U.S., National

Grid delivers electricity to approximately

3.3 million customers in Massachusetts,

New Hampshire, New York and Rhode

Island and manages the electricity

network on Long Island under an

agreement with the Long Island Power

Authority (LIPA). It is the largest distributor

of natural gas in the northeastern U.S.,

serving approximately 3.4 million

customers in Massachusetts, New

Hampshire, New York and Rhode

Island. National Grid also owns over

4,000 megawatts of contracted electricity

generation that provides power to over

one million LIPA customers.

When Selecting and Planting TreesDetermining where to plant atree is a decision that shouldnot be taken lightly. Many fac-tors need to be consideredprior to planting. When plan-ning what type of tree toplant, remember to look up,as well as down, to determinewhere the tree will be locatedin relation to both the over-head and underground utilitylines. The location of theselines will have a direct impacton your tree and planting site.

The ultimate mature height ofthe tree to be planted must bewithin the available overheadgrowing space. Proper treespecies selection and place-ment will assure the avoidanceof utility line conflicts in thefuture.

To help you select a type oflow growing, utility compatibletree species to plant, NationalGrid has compiled a list ofrecommended species foryour use. Download a copyfrom our Safety Section onour website www.nationalgridus.com, or contact our Distribution ForestryDepartment at 315-428-5987.

By selecting the “right treefor the right place”, you’ll notonly add value to your property,but you’ll help us avoid afuture need to prune “thewrong tree in the wrongplace”.