The enhanced environment, while less stressful to its human inhabitants, poses special challenges to its plant benefactors. The neophyte is quick to blame the problem entirely on lack of sunlight. While this is certainly a part of the problem, other factors must be considered. Maybe the trees were small when the landscape was installed and the shade has been getting progressively denser. Soils become severely deficient in organic matter when the leaves and grass clippings are continuously removed.
Trees can remove incredible amounts of water from the soil.
Most of the water comes from the upper soil layers where the roots of trees and turf share space. In addition to allowing more light to penetrate, increased air movement also improves conditions for turf. The turf is not the only thing to suffer. A weed treatment on turf under the trees may benefit the turf by reducing weed competition but at the same time damage the tree. Often mowing equipment is responsible for damage to tree roots or bark around the base of the trunk.