Cane maggot
Pegomya rubivora
0 host plants
Last updated
Young raspberry and blackberry cane tips suddenly wilt and discolor with purple streaking where the maggot girdles the stem just below the terminal bud; look for a tiny hole about 1mm in diameter near the tip. In caneberry patches, this pest emerges in late April, with wilting becoming obvious in May. The larva tunnels downward inside the cane before dropping to pupate.
Prune off infested canes several inches below wilted areas and dispose in sealed containers. Remove nearby wild blackberries to reduce pests. Keep caneberries vigorous with consistent irrigation. Parasitoid wasps provide excellent natural control when broad-spectrum pesticides are avoided.
Quick Reference
The cane maggot is the larva of a small fly. It feeds on the cambial tissues of red raspberry, blackcap, loganberry, and occasionally blackberry. The larvae are white and legless. The larvae feed downward in new canes. Canes are usually 1 to 3 ft in length when attacked. Young shoots wilt suddenly, and a purple discoloration appears where the maggot girdles the cane. This causes a distinct drooping condition. Canes also may show a characteristic swelling where feeding is occurring.