Ways To Tackle The Pea Weevil

Q. I notice when I shell peas that some of the pods contain peas that are being eaten by a small worm. What is this pest and how can I prevent it?

A. Wormy peas aren't terribly common, but infestations happen occasionally. The "worms" are actually beetle larvae or moth caterpillars. I'll describe both. You can take a close look at the next one you find and identify the critter.

Most often the problem is the pea weevil. The larvae are white, sickle-shaped, and about 1/4 inch when fully grown. They have a tiny brown head. Pea weevil eggs are laid on the outside of small pods, and the tiny hatched-out larva eats through the pod and into a seed. Only one larva develops in a single seed.

Pea moth larvae also drill into the pods but they are yellowish white caterpillars, about 1/2 inch long at maturity with dark areas at both ends. They are messier than the weevils, eating the seeds, nibbling at the pod itself and rifling the pod with silk webbing and frass (excrement).

When shelling peas, you can easily be surprised by a pea weevil. If you don't see the entry hole, you may not notice the pest at first. (The moral is: If you don't wear your glasses to shell peas, don't wear them to eat peas.)

Pea moths, on the other hand, are pretty hard to miss. The pods often yellow and ripen prematurely.

You can do lots of things to prevent these pests. Rotating where you grow your peas from year to year will help. Make sure you are not planting weevil-infested seed. Rip out and compost vines as soon as production tapers off. Send vines off with your yard-waste recycling, if you have had a bad year with either pest.

Practicing good garden sanitation is also important. Both insects need protection when over-wintering, so debris near the garden will help them survive. Weeding is especially important for pea moth, since wild peas and vetches can be alternate hosts.

If chemical control is needed for pea weevil, try a rotenone 1 percent dust when pods start to form. Three to four applications at four- to seven-day intervals may be needed. There are no chemicals registered for pea moth in home garden peas. Since the moths apparently don't emerge and start laying eggs until sometime in June, very early planting of fast-maturing varieties may be a way to avoid or at least minimize this pest problem.

Q. Why are the leaves of my lilac shrubs becoming blotchy and brown? It sure looks like a disease.

A. The lilac leaf miner is a small moth whose larvae feed between the upper and lower leaf surfaces during the initial stages of their life cycle. This damage is manifested by the slightly puffy olive to brownish blotches on the foliage.

During the last stages of its larval life cycle the caterpillars migrate out of the interior of the leaves and begin feeding on the outer surfaces, all the while rolling the leaves up. It generally pupates inside the rolled up leaves and eventually becomes the adult moth. There are three generations of this little beast each summer.

WSU Extension entomologists recommend picking off and destroying infested leaves as soon as they're noticed. Spray applications of orthene or diazinon in early May, early July and early September should also give excellent control.

The lilac leaf miner also attacks privets, ash and fringe trees. It is a widespread pest in this region.

Q. The leaves on my azalea have begun to swell up and some of the swollen ones have gotten brown. What horrible thing has descended on us?

A. Some azaleas are easily infected by a fungus organism that causes the galling you describe. Appropriately enough it's called azalea leaf gall. The leaves become thickened and are often covered with a whitish growth. They then turn hard and brown. Highly susceptible varieties are more prone to infection in shady areas. Plant these in full sun and where there is good air movement.

Gardening runs Friday in Scene and Sunday in Home/Real Estate. It is prepared by George Pinyuh and Holly Kennell, Washington State University/King County Cooperative Extension agents, Mary Robson, Master Gardener program assistant, and volunteer Master Gardeners.