Carrot Rust Fly
Chamaepsila rosae (formerly Psila rosae)
1 host plant
Last updated
Quick Reference
Order
Diptera
Type
fly (root maggot)
Host Plants
1
Peak Activity
First-generation adults May-June; second-generation July-August; third (parti...
What Damage Looks Like
Larvae tunnel into roots of carrots and related apiaceous crops, producing characteristic rust-colored frass-filled tunnels. Affected roots are unmarketable, prone to secondary rot, and often distorted. Foliage of heavily infested plants yellows and wilts. Damage is most severe on overwintered carrots and on the second generation in late summer." # Source: PNW Insect Management Handbook
Cultural Controls
- Cover crops with floating row cover from emergence through harvest to exclude egg-laying adults.
- Time plantings to avoid peak fly flights; early plantings harvested before second generation often escape damage.
- Rotate apiaceous crops; do not plant carrots in the same bed two consecutive years.
- Promptly harvest mature roots; do not leave roots in soil through fall when third-generation egg-laying occurs.
- Remove and destroy any infested roots; do not compost.
Host Plants (1)
Sources & References
Primary: PNW Insect Management Handbook
- WSU HortSense — Carrot Rust Fly
Data Maturity Structured Multiple sources. Expert review underway.