Strawberry Root-Weevil  luv2garden.com  - Abigal Gordon's Gardens ® Many species of root weevils feed on the young roots and crowns of strawberry plants. Adults will eat notches in the leaves, this damage is minimal, and unless you have a severe infestation will not generally damage your crop.. The larvae/Grubs However cause severe damage by tunneling in roots and crowns of plants. Damaged plants are stunted and darkened with leaves closely bunched. Plants may be weakened or even killed. Often the damage is restricted to a circular area in field due to the tendency of adults to gather in large groups. In their adult stage this insect is a small, dark snout beetle with rows of pits along their backs. Various species will differ slightly in size and color. The strawberry root weevil is black to light brown and 1/5 inch, the rough strawberry weevil chocolate brown and 1/4 inch, and the black vine weevil is black with small flecks of yellow on its back and 2/5 inch.

The grubs are white, 1/4 to 1/2 inch long, and a characteristic "c" shape. These grubs can be distinguished from other soil grubs because they are smaller and legless with a lighter colored head.

Root weevils overwinter in the soil as grubs that pupate in the spring. Adult beetles emerge in late May through June, feed at night on foliage leaving characteristic leaf notching, and hide during the day.

After feeding for as short as 10 to 14 days to as long as 30 to 60 days they begin laying eggs in soil near strawberry plants. The eggs hatch in late summer or early fall and the grubs start feeding on the roots. Most damage is caused by grubs after resuming feeding in the spring.

To prevent spread of root weevils to new beds, plow under old beds as soon as possible. Post harvest foliar sprays to control adult weevils prior to egg laying is recommended at renovation. Growers should watch for leaf notching as an indication of adult emergence.

 

Acephate	Targets adult stage. Apply in the early evening when adults emergence is complete but before egg laying for best results. Apply as per label instructions. There are many pesticides registered which contain acephate , many are labeled for use against fire ants but are also effective against snout beetles and weevils - read label before applying. If using on a relatively large area you may want to try Bonide Systemic Liquid which I have had success with in the past.
Beneficial Nematodes	Targets Larvae Stage - Apply in spring or fall when the larvae are most active. Follow label instructions / requirements.

 

Rough Strawberry Root Weevil  
Adults are slightly more than 1/4 inch long and resemble the strawberry root weevil with the exception of size. They are black, shiny, without scales and with coarse, punctures on the outer wings.

Adults are common on fruit trees in early summer.  Adults feed at night and hide during the day. Common victim of Praying Mantids