Fall is the perfect season for assessing the health of your trees. As leaves turn color and fall, you’ll have the opportunity to inspect the leaves from each tree for signs of disease. A diseased tree can spread infection, thus identifying the sickness and keeping fallen leaves away from the sick tree is important if that tree is to survive.
In yards with thick canopies of trees, homeowners may decide that allowing leaves to decompose naturally is the smartest and environmentally friendly option to pursue. However, if the tree is sick, those fallen leaves will reinfect the tree, contributing to its demise.
Signs of sickness can be seen by examining leaves for several problems including abnormal discoloration; foliage with spots and bumps; leaves that have fallen prematurely; cupped, twisted or otherwise deformed leaves; or insects or mites present on the leaves.
According to the Iowa State University Extension Service, leaves alone may not tell you that there is a problem. Homeowners should inspect tree trunks for signs of damage including roots that may have been run over by a lawn mower. Soil conditions, interaction with pavement, wind damage and other factors can contribute to tree problems. You may need to seek the assistance of your state’s extension service to have a diagnosis rendered and to pursue a course of action.
Leaves removed from the base of a tree can help that tree gain full access to air and sunlight, two important ingredients in tree health. Inadvertently, homeowners will sometimes allow leaves to remain in place, but that can attract fungi and insects. Better to remove the leaves and replace with fresh compost if you are concerned about your tree’s health. And, never use the leaves from a sick tree for your compost — only leaves from healthy trees should be added to your compost pile.