Symptoms

• Symptoms of herbicide damage vary in pear trees, depending on the herbicide used as well as the dispersal method of the chemical. Post-emergent, broad-leaved herbicides such as 2,4-D and dicamba may cause cupped, twisted or distorted leaves. Emerging leaves may have a straplike appearance. Nonselective broad-spectrum herbicides, such as glyphosate and paraquat, cause more extensive damage, such as branch dieback, leaf yellowing and possible death. The leaves may be yellow on only one side of the tree, depending on how the herbicide drifted.
  
  

Treatment

• If you suspect herbicide damage, immediately water the pear tree well to leach out any remaining residue. By the time the tree shows injury, the tree has already absorbed the herbicide and there is little you can do. Continue to provide good care, giving adequate water and an application of fertilizer to encourage vigorous growth. The tree will likely recover in time, depending on the herbicide and the dosage, although it may exhibit symptoms for two to three years. Pear fruit may not be safe to eat for at least the first season after herbicide injury.
  
  

Prevention

• Prevent herbicide damage to pear trees by following package directions carefully. Avoid applying herbicides on breezy or hot days. Winds can cause herbicides to drift onto desired plants, while herbicides may be vaporized, or turned to a gas form, on very hot days. Be aware of neighbors' herbicide activities, as well.
  
  

Considerations

• If you suspect herbicide injury, rule out other possible causes of damage first, such as mites, drought, soil compaction, root injury due to excavation, road salt, alkaline or acidic soils or excess fertilizer. Look at the plants near the pear tree, as well. They likely will be damaged if the cause is herbicide drift.