DAMAGE/SYMPTOMS Various growth abnormalities including twisting, cupping, and curling of leaves, stems, and twigs on broadleaf trees are common. Conifers can also show symptoms of needle and shoot distortion.

OCCURRENCE Synthetic auxin herbicides such as 2,4-D and dicamba are used to control broadleaf weeds in lawns and along roadsides. Drift of these herbicides occurs when spray particles move through the air during application or when they form a gaseous vapor due to volatilization after application.

SUSCEPTIBILITY/TOLERANCE Broadleaf trees and conifers are susceptible.

MANAGEMENT Wait and see if the tree recovers. Support tree health and limit further exposure to herbicides. Injury symptoms may occur for more than one year. To prevent damage from this type of herbicide, make sure to read and follow product labels. Avoid applying these herbicides under tree canopies. Also, avoid using these herbicides during windy weather, or when temperatures are forecast to be above 80 degrees.

 

A 2,4-D injury on grape. B 2,4-D injury to pine.

 

Photo showing a grapevine with large green leaves on the bottom and smaller, distorted leaves on the top.

Close up photo of pine needles that are bent and curled.