The fact sheet HGIC 2212 "Pecan Insects" is currently being reviewed and will be posted here as soon as it is complete.  The following is a transcript of the taped message on this subject which can be accessed by South Carolina residents using the Home & Garden Information Center's toll-free message system. 

Numerous insects are pests on pecan trees. These include the pecan weevil, hickory shuckworm, aphids, pecan spittlebug, mites, pecan phylloxera, twig girdler, and fall webworm.

The pecan weevil is ½-inch long. It is a reddish brown to gray beetle with a long snout. The immature forms called grubs are creamy white, curved and ½ inch long. Both the adults and grubs damage pecans. The adults feed on immature pecans until the kernel solidifies. These damaged nuts drop from the tree. Once the kernels harden, the adult females drill holes through the shucks and shells to lay their eggs. Grubs hatch out to feed on the kernels for several weeks. Traps are available commercially that can be used by the homeowner to reduce numbers of adult weevils.

The hickory shuckworm is a cream colored caterpillar and about 3/8 inch in length. It feeds in the immature pecan, which often falls to the ground early. Once the shells have hardened, the hickory shuckworm feeds in the shuck, which causes the shuck to stick to the nut.

There are a few things that homeowners can do to decrease insect problems on pecan trees. Proper sanitation can reduce insect pests significantly. This includes removing and destroying leaves after they fall in the autumn and quickly removing and destroying dead, diseased and damaged wood and nuts. The leaves, wood and nuts can provide pests with places to survive the winter.

Adequate insect control on pecans usually requires spraying trees. Sprays need to be timed accurately to be effective. Tree size may require spraying equipment that the homeowner does not have available. As with any pesticide, read and follow all label directions and precautions.