Trees Work Hard For Conservation in Urban Environments!
Within "Aesop's Fables" there is the story of the "City Mouse" and the "Country Mouse." In this story, the country mouse flees back to his quiet life in the woods, to get away from his cousin's "hard" life in the city. Well, city trees have a hard life as well and are not able to escape, but they do exhibit great benefits to the urban environment. Urban trees are surrounded by hard impervious surfaces and urban infrastructure, and other conditions that don't have to be endured by their country cousins that live in forested or other natural rural habitats.
Urbanization has displaced permanent vegetation such as trees, shrubs and grasses with hard surfaces which limits infiltration and increases the amount of water runoff into streams and lakes. Also, this change in the landuse has increased the rate of delivery of those waters to the receiving water body. This rapidly moving water runoff creates flooding and transports high levels of sediments, attached pollutants, and dissolved contaminants into surface water.
Increased runoff also causes streambank erosion, which results in degraded aquatic habitats and the accelerated deposition of sediments into rivers, lakes, and reservoirs. When rain moves rapidly off the land there is no time for recharging soil moisture or maintaining ground water base flows.
However, trees in an urban or suburban setting are capable of "hard work" in restoring and providing many important ecological services if they are selected, planted, and maintained properly.
Trees work hard to:
*Reduce Pollution. Trees, shrubs, and grasses planted as rain gardens, wetlands, and forested riparian buffers can help filter out contaminants by slowing down the polluted runoff and capturing it, letting sediments drop out and allowing soil or water microbes to breakdown pollutants.
*Help Manage Stormwater Volume. Conventional stormwater pipes just move the problem downstream, but the re-establishment of natural vegetation throughout a watershed will reduce stormwater runoff by soaking up the excess moisture. In one study, a 32 foot tall tree reduced runoff volume by 327 gallons.
*Stabilize Streambanks. While sod and ground cover hold topsoil in place, tree roots penetrate deeply and spread out, anchoring large blocks of soil. Densely planted trees and shrubs on fragile soils and slopes that are prone to erosion, work to keep foot traffic, bicycles, and motor vehicles from damaging these slopes.
*Buffer Landfills. Trees planted around Sanitary Landfills trap blowing debris and keep the litter out of streams and lakes.
Be a Conservation Crusader today! Plant trees for water quality! Your actions are powerful. What is done by one resident or business can affect the whole community and watershed. The cumulative effects of many individual actions can have significant impact on the overall landscape. For more information on trees and water quality, contact your county's Soil and Water Conservation District.