Field Identification
Yellow-and-black striped adults and brick-red hump-backed larvae that skeletonize potato, tomato, and eggplant foliage faster than you can say ‘resistance management.’ They overwinter as adults in field margins and laugh at many single-tactic programs.
Clusters of orange eggs on leaf undersides; larvae grow through four instars and drop to soil to pupate. Adults fly short distances, so infestations march field-to-field when solanums repeat.
How to Deal With It
Organic Control Methods
Spinosad, neem (azadirachtin), Beauveria bassiana, or pyrethrin—rotate modes and target small larvae; add spreader-sticker for waxy leaves.
Ladybugs, spined soldier bugs, and ground beetles eat eggs and larvae; Bacillus thuringiensis tenebrionis (Bt t) is specific to chrysomelid larvae where products are available.
Rotate potatoes with non-hosts; use straw mulch to interfere with larval movement; plant early trap crops of potato on field edges; flame or remove perimeter adults in spring.
Hand pick adults and larvae into soapy water; vacuum small plots; row cover seed potatoes until flowering if varieties allow.
Scout undersides of terminal leaves weekly; destroy overwintering sites along wooded edges; never rely on one organic spray all season.
Let Nature Handle It
Natural Enemies
- Spined Soldier Bug
- Ladybugs
- Ground Beetles (Carabidae)
- Parasitic Flies (Tachinidae)
Threat Map