Western corn rootwormWestern corn rootworm Eggs hatch mid- to late-May

Small larvae prune root hairs

Large larvae tunnel roots

Heavy feeding will reduce root mass

Confined to corn after cornUnlike Southern corn rootworm

Southern corn rootworm

Southern corn rootworm

Other Factors Affecting Abundance• Moist Soil• Reduced tillage• High historical pest pressure• High litter/mulch levels– Routine manure applications

Rotation is the most useful management tactic for Western Corn Rootworm

Why Rotate From Corn?

Adults lay eggs in soil during the

summer/fall

Larvae hatch mid- to late-May

Must feed on corn to survive

Pupate during June

Adults eat silk, pollen and foliage, then mate

Alternatives to Rotation

Relative Efficacy

Trade Name Chemical/rate S. Corn Rootworm

W. Corn Rootworm

Poncho 500 clothianidin 0.5 mg ai/kernel

Excellent Poor

Poncho 1250 clothianidin 1.25 mg ai/kernel

Excellent Fair

Cruiser Extreme 500

thiamethoxam 0.5 mg ai/kernel

Excellent Not labeled

Cruiser Extreme 1250

thiamethoxam 1.25 mg ai/kernel

Excellent Poor

Source: IPM Corn Insect, Disease, Nematode and Weed Control Recommendations for 2010 Alabama Cooperative Extension Center

Alternatives to RotationRelative Efficacy

Trade Name Event for Rootworm

W. Corn Rootworm

Agrisure RWAgrisure CB/LL/RWAgrisure 3000 GT

MIR604 Very good

Herculex RWHerculex XTRA

DAS-59122-7 Excellent

YieldGard RWYieldGard Plus

MON863 Fair-Good

YieldGard VT Rootworm/RR2YieldGard VT TripleGenuity VT Triple PRO

MON88017 Excellent

Genuity SmartStax MON88017 + DAS-59122-7

Excellent

Source: IPM Corn Insect, Disease, Nematode and Weed Control Recommendations for 2010 Alabama Cooperative Extension Center