New online tool assesses community tree canopy in Delaware

The Delaware Forest Service has unveiled a new online tool that uses geographic information systems software to help cities, towns and neighborhoods measure and increase their community tree canopy percentage. To view, go to www.de.gov/treecanopy.

Developed by Delaware Department of Agriculture GIS specialist Jimmy Kroon, the tool covers the entire First State. Municipalities, homeowner associations and neighborhoods can assess their current level of tree cover as a starting point to explore opportunities to plant new trees and maintain existing ones.

Tree canopy is important because trees provide numerous natural benefits for air and water quality, lower heating and cooling costs, a reduction in harmful UV radiation, and other environmental and social benefits. In particular, trees mitigate the soil erosion and stream pollution caused by impervious surfaces and stormwater runoff in urban areas. Studies show that trees can improve property values and provide scenic beauty, reduce summer peak temperatures, and even improve social ties among neighbors, factors that can help a community attract businesses and residents. One study found a 10 percent increase in tree cover was linked to a 12 percent decrease in crime.

Urban tree canopy assessment is used to help decision-makers understand their urban forest resources, particularly how much tree canopy currently exists and the amount that could exist. This enables citizens and public officials to identify "plantable space" to locate trees. The UTC assessment protocols have been applied to dozens of counties, cities, and towns in the United States and Canada. The assessments help inform UTC goals, prioritize tree-planting locations, establish urban forestry master plans, and justify spending and potential return on investment for urban forestry programs.

In Delaware, state forestry staff work with cities, towns, and communities to increase tree canopy through urban grants and technical assistance. Once the baseline of tree canopy has been established, urban foresters can help communities set goals to increase their percentage. Kesha Braunskill, Delaware Forest Service urban and community forestry program director, said the following Sussex County municipalities have adopted formal resolutions to increase and/or maintain their tree canopy: Delmar, Georgetown, Greenwood, Henlopen Acres, Laurel, Lewes, Millville and Rehoboth Beach.

"We hope this new online tool will help people focus on the many benefits of trees as well as the need to increase tree canopy statewide," said Braunskill. "We can magnify the numerous benefits of our urban forests by simply planting more trees in our communities and developments."

The Delaware Forest Service goal to keep and increase existing canopy is balanced against a concern that some people are taking out trees unnecessarily. In general, tree removals should be considered when the tree poses a hazard or a risk assessment shows a safety or tree health issue. In addition to asking the Delaware Forest Service for help, those with concerns should only consult companies with arborists certified by the International Society for Arboriculture. Because trees are so beneficial, when tree removal is necessary, the advice is "remove a tree, replace a tree."

As part of its the UCF program's annual tree grant process, applicants who seek funding for tree removals must provide for the tree's replacement, a requirement that has also been adopted through ordinances in Rehoboth, Lewes, and Wilmington. Every municipality that applies for an urban and community grant must also have a tree canopy goal.

There are currently tree canopy maps in PDF form for all incorporated municipalities, but the new GIS tool allows those outside municipal boundaries to also be aware of the benefits of keeping and increasing tree cover. Even homeowner associations can adopt tree canopy resolutions. The Delaware Forest Service offers technical assistance on tree planting, lists of recommended trees, site evaluation, tree ordinance and setting tree canopy goals. The agency also sponsors a website where residents can learn about the work of the urban and community forestry program and read a Tree Owner's Manual to learn about how to select, plant and care for new trees. For more information, go to www.delawaretrees.com.