HOST PLANTS:
Chinese, Persian, Japanese Ivory Silk Lilacs and common lilacs.
DAMAGE:
Young shoots rapidly turn black, wilt, and die; flowers darken and die. Leaf spots that are brown, water-soaked or black spots. Twigs may develop dark, sunken streaks, leading to girdling and branch death. Unlike fungal diseases, bacterial blight often causes a ‘shepherd’s crook’ or severe bending of young shoots.
DESCRIPTION AND LIFECYCLE:
Symptoms will appear in early spring during cool, rainy weather and after the leaf/flower have emerged.
CONTROL MEASURES:
Prune out infected, blackened branches, cutting 15 – 20 cms below the visibly affected area to ensure all pathogens are removed. Sanitize cutting tools with either 70% alcohol or 10% bleach. Remove and destroy fallen leaves and debris. Thin the crown to allow more air flow and sunlight penetration, which helps foliage dry faster. Water the tree at the base rather than using overhead sprinklers to keep leaves dry. Avoid high nitrogen fertilizers. Three applications of fungicide in the spring as the tree is leafing out.
CALL SHADY LANE EXPERT TREE CARE TO PROVIDE RECOMMENDATIONS
