Cole Crops

Sporadic or Minor Pests and Disorders: Planting to Rosette

  • Alternaria leafspot
  • Cabbage looper
  • Downy mildew
  • Imported cabbageworm
  • Vertebrates
  • Wind damage / Wind whip
Click on photos to enlarge. Names link to more information on identification and management.
Alternaria leafspot lesions.

Alternaria leafspot

Identification tips: Small, dark specks first develop on leaves and later enlarge into circular, tan spots (0.25–0.5 inch in diameter). The disease is favored by moist conditions.

Cabbage looper larva.

Cabbage looper

Identification tips: Larvae are green, smooth-skinned, about 1.5 inches long, and have two white stripes along each side. They eat ragged holes into leaves, and bore through and contaminate heads and leaves with frass.

Irregular yellow-brown spots caused by downy mildew, Peronospora parasitica.

Downy mildew

Identification tips: Infection begins as irregular yellow patches on leaves which later turn tan to light brown. White fluffy growth can develop on undersides of leaves. Infection occurs in cool moist weather.

Imported cabbageworm larva.

Imported cabbageworm

Identification tips: Larvae are green and hairy with an almost velvetlike appearance. They chew large irregular holes in leaves, bore into heads, and drop greenish brown fecal pellets.

Male house finch.


Identification tips: Mice, voles, and birds will feed on all stages of growth. Look for holes in the soil, seedlings that have been nipped off, or signs of feeding on leaves, curds, or heads. Also look for droppings near plants.

Wind damage to strawberry foliage.

Wind damage / Wind whip

Identification tips: High winds cause girdling and death of small seedlings, and surviving plants may wilt and fail to form a flowering head. Stems become brittle. Seedlings are most susceptible after weeding.

Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2016 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California

Accessibility   /PMG/C108/m108gpplantpestsyms.html revised: June 24, 2016. Contact webmaster.