Herbicide damage may manifest in a variety of symptoms, which include cupped, curled, or yellowed leaves, small leaves, or death of the entire plant. The herbicide class and the dosage to the plant determine which symptoms appear and their severity. Damage symptoms caused by this herbicide may not appear during the season of application, especially if application is made in autumn, but may appear the following spring as a proliferation of small shoots and leaves from buds. The plant will outgrow the injury if the dosage was not too high. Affected plants have spotted flower petals and buds that fail to open, often with woolly gray fungal spores on decaying tissue.
Twigs die back and large, diffuse, targetlike splotches form on canes.
Reduce humidity around plants by modifying irrigation, pruning, and reducing ground cover. Remove and dispose of fallen leaves and petals. Prune out infested canes, buds, and flowers. Botrytis is usually a problem only during spring and fall in most of California and during summer along coastal areas when the climate is cool and foggy. Stem cankers and dieback can be caused by a number of different fungi.