Walnut Husk Fly
Rhagoletis completa
7 host plants
Last updated
Data Coverage 1 of 6 dimensions
Walnut husk fly larvae tunnel through the outer husk of black walnut fruit, causing the husk to turn brown or black and become difficult to remove. Infested nuts develop dark staining on the shell and meat. Adult flies appear in late summer and lay eggs in developing husks. In regions with limited black walnut production, the impact of this pest is reduced.
Remove and destroy fallen husks and nuts in fall to eliminate breeding sites. For small numbers of trees, place baited traps to monitor and suppress adult fly activity. Clean up all dropped fruit and husks before winter. In regions with limited walnut production, chemical control is not standard practice.
Quick Reference
Order
Diptera
Type
chewing-insect
Host Plants
7
Cultural Controls
- Rake up and destroy fallen infested nuts.
- Naturally occurring predators and parasites also aid in controlling populations.
- Avoid use of broad-spectrum insecticides which kill beneficial insects.
Host Plants (7)
Aleurites moluccanus Candelnut, Kukui, Indian Walnut Juglans ailantifolia Japanese Walnut, Heartnut Juglans californica California Walnut, Southern California Walnut Juglans cinerea Butternut Juglans microcarpa Texas Walnut, Little Walnut Juglans nigra Black Walnut Juglans regia English Walnut, Persian Walnut