How to Manage Pests

Trapping

Monitor adult weevils by placing burlap bags on the ground near the trunk beneath plants or by snugly wrapping burlap strips around the basal trunk. Once or twice a week gently unwrap trunks or lift burlap from the ground and inspect underneath for adult weevils that hide there during the day.

Adult weevils can also be captured using a pitfall trap constructed from a several-inches-deep, wide-mouthed plastic cup or dish and a funnel or smaller tapered cup. Cut off most of the funnel's spout or the bottom of the smaller cup and insert it snugly into the larger cup with the hole pointed down. A single plastic cup may be used if the sides are regularly lubricated with oil to prevent the beetles from climbing out. Bury your trap so its top is flush with, or slightly below, the soil surface. Drill small holes in the bottom of the cup so that water can drain out. Alternatively, keep irrigation water out by covering each trap with an inverted gallon pot after first cutting legs into the rim. Bury one or more traps as close to the trunk as possible beneath the canopy of each of several host plants. Check each trap weekly. If you find beneficial predaceous carabid beetles, release them as they help to control weevils.

Trap boards can also be placed on the ground beneath plants. Boards may be less effective in trapping weevils than pitfall or burlap traps are.