Strawberry crown borer
Tyloderma fragariae (Riley)
Adults are dark brown flightless snout beetles possessing 3 darker
spots on each wing cover (elytron) and approximately 4 mm in length
(Davidson & Lyon 1987). Larvae are creamy-white in color, legless,
and can be found feeding in the crowns.
Biology and damage:
The strawberry crown borer is considered to be native to North
America, and is prominent in the eastern half of the United States. As
the name of this insect would suggest, damage is caused by the larvae
boring into the crown of the plant (Davidson & Lyon 1987). The
crown can be so hollowed out following the weevil feeding that death
occurs to the plant. In addition, adults feed on leaves and may chew
holes in the crown prior to oviposition. There is one generation per
year. Adults overwinter and become active around the time of strawberry
blossom. Eggs are deposited in the crown.
Crop rotation helps to control this pest since the beetles migrate only
by adult crawling along the ground. Also, avoid planting strawberry
patches closer than 300 yards to old plantings (Davidson & Lyon
1987). In addition, deep plowing and compacting of the soil destroys
many hibernating weevils.
Further information: See also the Northwest InfoNet page on strawberry
borer (However, the color plate in that source is an
incorrectly labeled dipteran.)