Tree and Shrub Disease

Bacterial Leaf Scorch: Visually, bacterial leaf scorch appears as browning or discoloring of the leaf margin which gradually consumes the remaining tissue of the leaf. Bacterial leaf scorch reoccurs year after year, slowly defoliating the tree at the crown, one random branch at a time. Bacterial leaf scorch is transferred from tree to tree by leafhopper and treehopper insects. There are no known cures for bacterial leaf scorch and it is recommended that homeowners or property managers who face this problem in their landscape try and prolong the life of their tree to the best of their ability; water, fertilization and pruning can help extend the life.

Non-parasitic Leaf Scorch first appears as a uniform discoloration on the margin of the leaf then moves to the remaining leaf tissue, often leaving the leaf yellow or brown before the leaf dries out and drops prematurely. Unlike many of the diseases listed here, this leaf scorch is caused by environmental factors, chemical injury or other unfavorable conditions. Leaf scorch can leave the tree weakened and more susceptible to insect or other disease activity; however leaf scorch can be prevented or effectively controlled.

The usual cause of leaf scorch is drought-like conditions with hot temperatures. The leaf discolors and dries up simply because there is not enough water to travel through the roots to the leaf. Poor, heavy soil can also prohibit the tree from receiving enough moisture (and nutrients) while also inhibiting the root structure. A deep root fertilization would benefit the tree because it will aerate the soil in the root zone, add nutrients and add moisture. Ensure that the tree receives a heavy watering during dry periods, especially is the tree does not have shelter from the direct sunlight.

Disease Development Favored by: Hot, dry weather Soil compaction Poor soil quality (Bacterial: insects) Corrective Measures: Water during dry spells Deep root fertilization to add nutrients and aerate the soil Apply preventative fungicides and insecticides the following leaf scorch Mulch around the tree or shrub to hold moisture in the soil Prune if needed (this will help the tree conserve energy)

Leaf scorch, non-parasitic

Bacterial Leaf Scorch