Includes
Green peach aphid (Myzus persicae)
Willow-carrot aphid (Cavariella aegopodii)
Pest description and crop damage The wingless form of the green peach aphid is yellowish green in color. The winged form has a black head and thorax, and a pale green abdomen marked with dark bands on the top and sides with a distinct dark patch on the top. The wingless form of the willow-carrot aphid is pale green and oval-shaped. Green peach aphids and willow-carrot aphids are vectors of several important virus diseases in carrots.
Scouting and thresholds No treatment threshold has been determined for aphids on carrots grown for seed. Growers should inspect plant foliage and umbels for aphid activity. Also, look for evidence of predators. Treatment may be warranted if aphid populations increase drastically over time or if virus diseases vectored by aphids are of concern.
Management-chemical control
- bifenthrin (Bifenture EC) at 5.1 to 6.4 fl oz/A (0.08 to 0.1 lb ai/A). REI 12 hr. This product is highly toxic to bees exposed to direct treatment or residues on blooming crops or weeds. Use prebloom (allow 5 days before introducing pollinators) or after pollination. There are some restrictions pertaining to rotation crops. Extremely toxic to fish and aquatic invertebrates, so follow buffer zone restrictions on the label.
- pymetrozine (Fulfill) at 2.75 oz/A (1.38 oz ai/A). PHI 14 days. REI 12 hr. This insecticide works primarily by ingestion, but also has some contact activity. Aphids stop feeding shortly after exposure, but may remain on the plant foliage until they die, which is usually within 2 to 7 days. This product has residual activity in the plant. Allow 7 days between applications. Do not exceed 5.5 oz/A (2.76 oz ai/A) per season. The addition of a penetrating type spray adjuvant is recommended. Do not apply through any type of irrigation system. Fulfill is toxic to bees exposed to direct application. Applications to blooming crops must be between late evening and early morning to coincide with minimal bee activity. No portion of treated plants can be used for food or feed. 24c SLNs: OR-180013 (expires 12/31/28), WA-190003 (expires 12/31/29). Oregon and Washington only.
See also: