Colorado Potato Beetle Reference Page

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Colorado Potato Beetle Reference Page

Potato, Irish—Colorado potato beetle

Leptinotarsa decemlineata ID photos: fact page (pdf):

Pest description and crop damage The Colorado potato beetle (CPB) is a yellow and black striped beetle, about ¹⁄2 inch long and ¹/4 inch wide. Larvae are reddish orange, with two rows of black spots on each side. Yellow egg clusters are found on the undersides of leaves.

This beetle can cause complete defoliation and nearly complete crop loss if allowed to reproduce unchecked. Both larvae and adults feed on potato foliage throughout the season. In cool climates, the beetle undergoes only one generation per season, but in warmer areas, such as the southern Columbia Basin, it may have three generations.

Management—chemical control

The CPB has developed very high levels of resistance to insecticides in many parts of the country. Fortunately, most populations in the PNW are still susceptible to almost all labeled products. The lessons learned by potato growers in the East should still be heeded here:

Control generally should not be applied until egg hatch begins. Border sprays are sometimes an economical choice, especially early in the season before populations build up.

Caution Pyrethroids applications make aphid management more difficult, and can lead to outbreaks of spider mites. Please note the dagger symbol—†—used throughout this section to identify pyrethroids.

1. abamectin (Agri-Mek 0.15EC) at 8 to 16 fl oz product/a as foliar treatment. PHI 14 days. Apply in at least 20 gal/a of water.

2. ‡ acetamiprid (Assail 70 WP) at 1.0 to 1.7 oz product per acre as foliar treatment. Maximum of four applications per season. PHI 7 days. See “Special Note about Resistance Management” at the beginning of the potato section.

3. aldicarb (Temik 15G NW) at 14 to 20 lb product/a in furrow at planting. PHI 150 days. Positive displacement applicators only. Certification required.

4. Bacillus thuringiensis subsp. tenebrionis (Novodor). Foliar spray. PHI 0 days. Most effective on small larvae.

5. carbaryl (Sevin) at 1 to 2 lb ai/a as foliar treatment. PHI 7 days.

6. carbofuran—

a. Furadan 4F at 0.5 to 1 lb ai/a as foliar treatment. PHI 14 days. Do not apply by chemigation.

b. Furadan 4F at 3 lb ai/a applied from planting to 4-inch rosette. PHI 14 days. Do not apply by chemigation. ID, OR, WA 24(c).

7. cryolite (Kryocide: sodium aluminofluoride) at 10 to 12 lb product/a as foliar treatment. PHI 14 days.

8. † cyfluthrin

See

9. † deltamethrin (Decis 0.2 EC, Battalion 0.2 EC) at 1.5 to 2.4 oz product/a as a foliar treatment. PHI 3 days. Maximum of 12.0 oz per season.

10. ‡ dinotefuran (Venom 20 SG) at 0.33 lb product/a as a foliar treatment or 1.40 to 1.65 lb product/a as a soil treatment at preplant or planting, or as a sidedress. PHI 7 days. Maximum of 0.99 lb applied to foliage per season. See “Special Note about Resistance Management” at the beginning of the potato section.

11. endosulfan—

Endosulfan is more effective above 75°F.

12. † esfenvalerate (Asana XL) at 0.03 to 0.05 lb ai/a as foliar treatment. PHI 7 days. Do not exceed 0.35 lb ai/a per season.

13. ‡ imidacloprid—

See

14. methamidophos (Monitor) at 0.75 to 1 lb ai/a or 1.5 to 2 pints/a product as foliar treatment. PHI 14 days. Apply no more than 4 lb ai/a per season.

15. methyl parathion (Penncap-M, Declare) at 0.5 to 1.5 lb ai/a as foliar treatment. PHI 5 days.

16. novaluron (Rimon) at 9 to 12 fl oz/a product as foliar treatment. PHI 14 days. No more than two applications per year.

17. oxamyl—

Do not apply more than 9 lb ai/a per year. Foliar applications may be made by chemigation.

18. † permethrin (Ambush, Pounce, etc.) at 0.05 to 0.2 lb ai/a as foliar treatment. PHI 14 days. Do not exceed 1.6 lb ai/a per season.

19. phorate (Thimet 20G, Phorate 20G) at 2.3 to 3.5 lb ai/1,000 ft of row. PHI 90 days. Federal label for Thimet 20G allows postemergence application on “light or sandy soil” only. 24(c) labels for Phorate 20G in ID, OR (except Lake County), and WA allow for postemergence application on any soil.

20. phosmet (Imidan) at 1.33 to 2.5 lb product/a as a foliar treatment. PHI 7 days at the low rate, 21 days at anything above the low rate. Apply no more than 6.66 lb/a per season. Rates above 1.33 lb are allowed only under a 24(c) label in WA.

21. spinosad (Success, Entrust) at 3 to 6 fl oz product/a as foliar treatment. PHI 7 days. May be applied by chemigation. Entrust is approved for organic production.

22. ‡ thiamethoxam—

Do not apply more than 0.078 lb ai/a per year of thiamethoxam.

a. Actara at 1.5 oz product/a as foliar treatment. PHI 14 days. See “Special Note about Resistance Management” at the beginning of the potato section.
b. Platinum at 5 to 8 fl oz product/a at planting sprayed in-furrow, impregnated in granular fertilizer and applied before or at planting, or sidedress at emergence.
c. Cruiser at 0.11 to 0.16 oz product per 100 lb seed pieces.

Source: 2007 PNW Insect Management Handbook