Parasites That Destroy Prickly Pear Cactus

Prickly Pear Borer

• The prickly pear borer is one of the most common parasites feeding on this plant. It usually appears in May. The adults feature black-and-red markings. They feed around the edges of the younger pads. They infest the stems of the plant, and their larvae infest deep within the plant's pads. These pests slow the growth of the plant and even kill the plant itself. Use horticultural knives to remove borer larvae from the plant and your hand to remove the adults. Insecticides that will work include malathion and endosulfan.

Less Common Insects

• Twice as large as the prickly pear borer, the spine borer appears earlier in the season, in late April or early May. These parasites feature a dark, cross-shaped mark on their back. They establish themselves in the base of the plant's spine. Control and manage them with folidol during the early stages of infestation. Other insects attacking prickly pear are the cochineal insect, which lays 150 to 160 eggs in a lifetime; the blind June beetle, which feeds on the roots and underground sections of the plant; and the opuntia megacantha, which comes out during the late summer months leaving moldy secretions on the plant leaves.

Chinch Bugs

• The chinch bug is among the many parasites that appear during the warm months. These insects lay eggs around the pad and spine of the plant, and their eggs can hatch in groups of five to 15. They reproduce throughout the year and feed on the outer layers the plant. Control chinch bugs with insecticides, the most effective ones being malathion, endrin and ethyl parathion. The most common chinch bugs are the gray and the chinch bug.

Grubs and Worms

• The white grub is the most common pest on prickly pear plants and is one of the many grubs and worms that can be found on your plant. This high-plains insect with egg batches of 30 to 50 can produce a large infestation in just weeks. The larvae form cocoons within the plant. They become the biggest problem during the months of July and August. As with the prickly pear borer, use malathion and endosulfan to manage these pests on your tree. Other grubs and worms with similar problems and solutions include wireworms, which can lay hundreds of eggs near the roots of your plant; moneilema variolaris, which bore through the plant stems; and brown garden snails, which feed on the surface pads of the prickly pear.