Pieris rapae
Pest description and crop damage Larvae are green and very hairy, with an almost velvet-like appearance. Older larvae may be up to 1 inch long. They often have one faint yellow-orange stripe down their backs and broken stripes along the sides.
Management-chemical control
- azadirachtin (Aza-Direct, Neemix 4.5)-See label for rates. PHI 0 days. This is a botanical insecticide with ingestion and contact action that kills larvae by interfering with molting; also reduces damage by repelling and deterring feeding. Repeat in 7- to 10- day intervals beginning at the first sign of infestation when pests are immature. Repeated applications break the life cycle of the pest. Some formulations are OMRI-listed for organic use.
- zeta-cypermethrin (Mustang) at 3.4 to 4.3 fl oz/A (0.04 to 0.05 lb ai/A). PHI 1 day. REI 12 hr. Do not exceed 25.8 fl oz/A (0.3 lb ai/A) per season. Do not make applications less than 4 days apart. This product is highly toxic to bees exposed to direct treatment on blooming crops or weeds. Toxic to fish and aquatic organisms. Do not apply by ground within 25 feet of bodies of water. Do not apply by ULV aerial application within 450 feet or by non-ULV aerial application within 150 feet of bodies of water. Maintain a minimum 10-ft wide vegetative filter strip between the field and down gradient aquatic habitat.