Water is a very precious resource on this planet. The quality of our water is becoming more questionable. Contaminants from agricultural, industrial and community sources makes many of our waters unsuitable for swimming, drinking or for aquatic life. Water quality is another environmental issue that trees can improve the planet. By trapping contaminants and slowing runoff, trees can alleviate many of the potential problems before they enter a body of water.

Land use is one cause of water problems. Development, agriculture and forestry have permanently altered many areas of vegetation. The vegetation used to perform the function of slowing runoff and filtering out pollutants. With the loss of vegetation near watersheds, water flows more rapidly, moving along greater amounts of pollutants and contributing to stream bank erosion. When vegetation is present, the water flow is slowed and soil particles and nutrients can be contained within a plant’s roots. Trees serve as the best filter, as they have a large amount of biomass to process and store pollutants.

Trees can be reincorporated into the altered environment in many ways. Windbreaks, shelterbelts and riparian buffer zones all serve to protect watersheds. By trapping airborne pollutants in foliage, windbreaks can prevent large amounts of dust and debris from ever reaching streams or lakes. Due to their location, riparian buffer zones often benefit watershed the most. They are the final line of defense before water enters the system. Here, the roots of trees and other vegetation absorb excess nutrients and pollutants as they also slow down incoming run off. Trees then store needed nutrients in their wood and release excess filtered water through their foliage into the atmosphere.

In agricultural land, other agro forestry techniques can also be utilized to protect water quality. Use of alley cropping includes rows of crops between rows of trees. Trees trap airborne dust, prevent soil erosion and absorb excess fertilizers and/or contaminants from animal waste. This technique is called silvopasture and can also create a secondary income from tree products.

Along community or urban roadways and parking areas, planting islands of vegetation can significantly absorb and slow down storm water runoff. These islands can be incorporated into large areas of paved space to create permeable surfaces where water can drain.

On a larger scale, acres of trees can create natural wastewater treatment and storm water management without the large price tag of building facilities. By absorbing excess runoff and transpiring it into the atmosphere, trees reduce the amount of water that needs to be managed. Any water intake is filtered through the tree’s system before it is released, reducing water pollution. Large and growing trees can contribute significantly to these municipal projects as they uptake excess nutrients and pollutants rapidly.

As man continues to pave his way to the future, man also needs to adapt in order to protect and improve his environment. Incorporating plantings of trees in any new development will increase water and air quality and help better manage the land of which we are stewards.


For additional information concerning the care and maintenance of trees and shrubs check out: