March 4, 2010
Tree Trimming Program Among Best in Nation
For the 9th year in a row, Austin Energy has been named a Tree Line USA Utility by the Arbor Day Foundation, a non-profit organization dedicated to tree planting and environmental stewardship. This sought after designation goes to utilities that use best practice tree pruning techniques, have tree planting programs, and provide public educationontree placement and care. Austin Energy is one of just two out of 72 municipally-owned utilities in Texas to receive the recognition.
Austin Energy seeks to strike a balance between preserving the natural beauty of the city’s trees and protecting the utility’s power lines. In Austin, tree limbs are the most common cause of power outages during stormy weather. The National Electrical Safety Code, which has been adopted by Texas, requires that utilities maintain clearance between power lines and equipment and tree limbs.
Austin Energy models its tree pruning program after the four-to-five year trim cycle standard that electric utilities use nationwide. This means that trees will be pruned sufficiently to keep limbs clear of the power lines for that length of time. Each year in Austin, trees are trimmed along 400 miles of power lines involving some 12,000 properties.
The Austin Energy program uses best practice pruning techniques including the avoidance of topping, tipping, removing branch collars and leaving long stubs. Trimmers generally cut back trees to their natural branch collar which is healthier for the trees and helps to minimize new sprouts. Annual training is required for employees, supervisors, and contract workers who perform pruning work for the utility.
Austin Energy is one of only a few utilities nationwide that communicates with each property owner in advance of trimming. The utility employs 13 certified arborists to manage the work of its contract tree trimming crews. The contractors use another dozen certified arborists who meet with each property owner and provide a written description of the pruning that is to be done.
The utility funds the planting of about 5,000 trees each year in Austin through various programs to help beautify neighborhoods and reduce the urban heat island effect.
NeighborWoods – A program that identifies neighborhoods that lack sufficient tree canopy. This program identifies and marks best locations for trees on each property. Homeowners who pledge to plant and care for new trees are provided the right tree for the right location from a variety of species. Austin Energy funds the distribution of about 3,500 trees a year through this program, with about 25,000 trees distributed since 2002. The program is administered by TreeFolks, a local non-profit organization.
Austin Community Trees – Plants trees along streets and sidewalks, potentially cooling daytime temperatures in neighborhoods by up to four degrees. The ACT program has planted almost 2,000 trees since 2005.
Large Trees for City Streetscapes – Created in 2004 to mitigate the urban heat island effect. Provides 5-inch caliper trees to shade City right of ways and sidewalks in commercial and public areas such as downtown. The number of tree plantings varies from year to year but last year totaled 65.
Tree Trimming Program- Over the past 10 years, Austin Energy has funded the planting of an additional 9,000 trees to replace trees removed during the tree trimming process due to poor health or because too much pruning would be required to provide proper clearance from power lines.
Austin Energy spends about $10 million annually on its Vegetation Management Program. The utility also has pilots under way to test the use of extra tall power poles in older neighborhoods with very large mature trees.