Module 4: Tree Pruning and Maintenance

Mulching
Urban trees benefit from woody organic mulches applied to the root zone.   Mulching reduces competition from turf and weeds, moderates soil moisture and temperature, helps prevent mower and string trimmer injuries, and creates a better environment for soil microbes associated with trees.   An ideal mulch consists of coarse wood chips several inches thick, spread over as much of the root zone as practical, but not against the trunk.

Fertilization
The application of moderate rates of slow-release nitrogen fertilizer materials to the soil over the root zone of young to mature trees is beneficial to their growth and survival.   Excessive rates should be avoided and trees past maturity or in senescence should not be fertilized.

Plant Health Care
It is now recognized that the best way to protect trees from pests such as insects and disease is be proactive rather than reactive.   The practice of Plant Health Care begins with proper selection and planting, continues with good care to reduce stresses, and implements a careful program of   scouting, monitoring, and use of integrated pest management.   Good tree care involves maintaining trees in balance with the environment and other organisms.   When possible, protect groves of trees, not just individual trees.   Protect the growing space of the tree as well as the tree itself.   Try to avoid drastic change around trees as they can only respond incrementally.   Too much of anything is usually detrimental.   As a general rule, trees can not be cured of problems (saved), but with proper care they may be preserved.

Benefits of training trees for structure and form careful, thoughtful pruning of trees in order to train their structure and form will provide many benefits.   Training will influence future performance, landscape potential, and safety.   Correct pruning of young trees will improve structural stability, increase tree longevity, and decrease maintenance costs.   Trained trees will have fewer branches, but will have better spacing.   They will have fewer structural defects when mature, thus reducing the need for costly corrective measures later.   The process of training young trees directs growth to fulfill the landscape function, reduces structural defects that may lead to tree failure, and ultimately decrease hazard potential and liability risks.  Well-maintained trees are an asset to any landscape.