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lambda-cyhalothrin (Warrior II)

Warrior II has contact and ingestion activity. It is toxic to many kinds of insects with a relatively long duration of impact from residues. This and other pyrethroid insecticides (Group 3) should not be used mid-season because they kill predatory insects that help to keep aphids, psyllids, thrips, and spider mites in check. Warrior II is not systemic or translaminar, but residues should persist for 7-14 days. Re-apply if needed to protect new foliage. High water volumes help with product distribution. Make only two consecutive applications before rotating to an insecticide with a different MOA. Similar products with lambda-cyhalothrin are available but use rates vary.

Restricted
Material Type: Insecticides and Repellents
Chemical Classification: Pyrethroid
Signal Word: Warning
Formulation: Liquid
EPA Number: 100-1295

Usage for lambda-cyhalothrin on Potatoes

Max Application per Season: 7.68fl oz

Emergence to Row Closure

Target Application per Acre REI PHI MOA Eff. Notes
Aphid 1.28-1.92 fl oz 24 h 7 d 3 F-P Apply before aphid populations start to build, and it is before mid-June. Not particularly effective for aphids.
Armyworms, Cutworms, Loopers fl oz 24 h 7 d 3 G Apply when small caterpillars are present, but only if it’s before mid-June.
Beet Leafhopper 0.96-1.6 fl oz 24 h 7 d 3 G Apply in May and June to minimize spread of phytoplasma diseases (e.g., purple top) if BLH populations are building.
Colorado Potato Beetle 1.28-1.92 fl oz 24 h 7 d 3 G Apply at 50% egg hatch while larvae are small, but only if it’s before mid-June.
Lygus Bugs 1.28-1.92 fl oz 24 h 7 d 3 G Apply when nymphs are present before mid-June.
Potato Psyllid 1.28-1.92 fl oz 24 h 7 d 3 G (n+a) Apply when adult psyllids are migrating into the field and it’s before mid-June. If early nymphs are present, it may not control nymphs on the underside of leaves where the product is not well distributed.

Tuber Bulking

Target Application per Acre REI PHI MOA Eff. Notes
Aphid 1.28-1.92 fl oz 24 h 7 d 3 P Use of pyrethroid insecticides is not recommended mid-season. Not very effective for aphids. If used, apply before aphid populations build. Monitor for subsequent pest outbreaks.
Armyworms, Cutworms, Loopers fl oz 24 h 7 d 3 P Use of pyrethroid insecticides is not recommended mid-season. If used, apply when small caterpillars are present. Monitor for subsequent pest outbreaks.
Colorado Potato Beetle 1.28-1.92 fl oz 24 h 7 d 3 P Use of pyrethroid insecticides is not recommended mid-season. If used, apply when larvae are small. Monitor for subsequent pest outbreaks.
Lygus Bugs 1.28-1.92 fl oz 24 h 7 d 3 P Use of pyrethroid insecticides is not recommended mid-season. If used, apply when nymphs are present. Monitor for subsequent pest outbreaks.
Potato Psyllid 1.28-1.92 fl oz 24 h 7 d 3 P Use of pyrethroid insecticides is not recommended mid-season. If used, apply when psyllids are present. It may not control nymphs on the underside of leaves where the product is not well distributed. Monitor for subsequent pest outbreaks.

Late Tuber Bulking to Harvest

Target Application per Acre REI PHI MOA Eff. Notes
Colorado Potato Beetle 1.28-1.92 fl oz 24 h 7 d 3 G-F Apply at 50% egg hatch while larvae are small.
Potato Psyllid 1.28-1.92 fl oz 24 h 7 d 3 G (n+a) Apply when psyllids are migrating into the field.
Tuberworm 1.28-1.92 fl oz 24 h 7 d 3 E Target PTW larvae feeding in the canopy in the weeks prior to vine desiccation or harvest. PHI is 7-days. Ground or air application to dense canopies may not provide sufficient coverage or lower leaves, use sufficient water carrier. Use only 0.1 to 0.2-inches of water with chemigation.