integrated pest management

Strawberry Sap Beetle
Stelidota geminata

Adult strawberry sap beetles, Stelidota geminata, are less than 1/8 inch long, oval-shaped, and mottled brown in color. They fly into strawberry plantings from wooded areas at about the time berries begin to ripen; they are particularly attracted to over-ripe berries.

Their feeding leaves deep cavities in berries, and females then deposit eggs on the injured fruit. Although larvae feed in berries, they usually are unnoticed because the fruit has already begun to decompose as a result of damage caused by adults. Because over-ripe fruit is especially attractive to sap beetles, damage is often greatest in U-Pick operations where pickers leave large numbers of ripe and over-ripe berries in the field.

Strawberry sap beetles are best controlled by timely and complete ("clean") picking and the removal of over-ripe and damaged berries. Because sap beetle populations usually do not build up until the picking cycle is underway, the use of insecticides is limited by frequent harvests. Certain insecticides are effective against sap beetles but can be used in strawberries only if the preharvest interval of 3-5 days is obeyed. Placing "trap buckets" of over-ripe fruit outside field borders can intercept immigrating beetles and reduce numbers in the crop.