Pecan trees are native to central and eastern North America. Although there are over 500 varieties of pecan, only a few are prized for cooking. A hardy deciduous trees in the same family as hickory and walnut, pecans are susceptible to a number of diseases that can result in low yields or even tree death. Amongst these is pecan tree bunch disease. What is bunch disease in pecan trees and how do you go about treating pecan bunch disease? Read on to learn more.
What is Bunch Disease in Pecan Trees?
Pecan tree bunch disease is a mycoplasma organism that attacks the tree’s foliage and buds. The characteristic symptoms include bunches of willowy shoots growing in bushy patches on the tree. These are the result of an abnormal forcing of lateral buds. The bushy areas of willowy shoots may occur on one branch or a multitude of limbs.
The disease develops during the winter and symptoms manifest in late spring to early summer. Infected leaves tend to develop more rapidly than uninfected foliage. There is some thought that the pathogen is transmitted through insect contact, most likely by leafhoppers.
Treating Pecan Bunch Disease
There is no known control for bunch disease of pecan trees. Any infected areas of the tree should be pruned out immediately. Prune the affected shoots to several feet (0.5 to 1.5 m.) below the area of the symptoms. If a tree appears to be severely infected, it should be removed in its entirety and destroyed.
There are varieties that are more disease resistant than others. These include:
Do not plant any new trees or other plants in the area since the disease can be passed on through the soil. If top working, use one of the more disease resistant cultivars above. Use only graft wood from bunch disease free trees for propagation.
For additional information on bunch tree disease in pecans, contact your local county extension office.