Lygus bug Reference Page

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Lygus Bug Resource Page

Lygus Bug Reference Page

Hemiptera (True bugs): Miridae(Plant bugs)
Species:Lygus hesperus
Key Hosts: alfalfa, alfalfa seed, dry beans, red clover, mint, other crops and several weed species

Pest description and crop damage Adults are ³⁄16 inch long and have a light yellow “V” on the back. Lygus bugs pierce buds and suck sap, injuring both vegetative and reproductive buds. Blasted buds, blossom drop, and shriveled seed result from feeding by this pest.

Sampling and thresholds

First application— Apply insecticides on warm days in late May as populations approach three per sweep and appear to be increasing. Use at least 10 gal spray/a for aerial applications.

Second application— May need to be applied during bloom if lygus bugs (adults plus nymphs) reach three to four per 180-degree sweep of a 15-inch net but before majority of the field population of nymphs reach fourth instar. Use bifenthrin (Capture 2EC). Naled (Dibrom ) is not recommended during early season if leafcutter or alkalai bees are active. Capture 2EC (bifenthrin) at the lower label rate tends to be least destructive to beneficials.

Management—chemical control

1. bifenthrin—

2. dimethoate at 0.25 to 0.5 lb ai/a. PHI 7 days. Do not use any crop part for feed within 10 days of treatment. Do not apply to bloom.

3. endosulfan (Thiodan ) at 1 lb ai/a. PHI 21 days. Do not make more than two applications per season. Do not graze treated fields or feed treated forage, crop residue, or seed millings. SLN ID-980012, ID-980003, ID-970009, ID-030004; WA-990032, WA-030024; OR-030007 expires 12/31/06.

4. formetanate—

Carzol CDMS website access to labels and MSDS pages

5. gamma cyhalothrin (Pro-axis) at 0.01 to 0.015 lb ai/a. PHI 1 day for forage, and 7 days for hay. REI 1 day. Do not apply more than 0.06 lb ai/a per season.

6. lambda-cyhalothrin (Warrior) at 0.015 to 0.03 lb ai/a. PHI 1 day for forage, and 7 days for hay. Do not apply more than 0.03 lb ai/a per cutting or 0.12 lb ai/a per season. Do not apply on the ground within 25 ft, by air within 150 ft, or by ULV within 450 ft of aquatic habitat.

7. malathion at 1 to 1.25 lb ai/a. PHI zero days.

8. methidathion (Supracide ) at 0.5 to 1 lb ai/a. PHI 7 days. No part of treated field may be used as feed. Lower rates are recommended in new seed-growing areas to help prevent the development of insecticidal resistance. SLN ID-000005; OR-000010 expires 12/31/07.

9. methyl parathion (Declare) at 0.25 to 0.5 lb ai/a. PHI 15 days for harvest, cutting, or grazing.

10. naled (Dibrom) at 1 to 1.5 lb ai/a at 7-day intervals. No part of treated field may be used as feed. PHI 0.5 day. SLN ID-010017; OR-990032 expires 12/31/06. ID and OR only.

11. permethrin at 0.05 to 0.2 lb ai/a. PHI zero days at rates less than 0.1 lb ai/a, or 14 days for rate equal to or greater than 0.1 lb ai/a. Do not apply more than 0.2 lb ai/a per season If used during bloom, remove bees from field for 2 to 3 days.

12. tralomethrin (Scout X-tra) at 0.013 to 0.019 lb ai/a. Do not apply more than 0.019 lb/a per treatment. Do not make more than three applications per season. No part of crop may be used as feed. Do not apply by ground within 25 ft or by air within 75 ft of aquatic habitat. SLN ID-930010. ID only.

13. zeta-cypermethrin (Mustang) at 0.035 to 0.05 lb ai/a. PHI 3 days for cutting or grazing; 7 days harvesting seed. Do not reapply within 7 days of last application. A maximum of 0.05 lb ai/a per cutting and 0.15 per season.

Resistance management Growers are advised strongly to rotate insecticide families (i.e. organophosphates, carbamates, and synthetic pyrethroids) in their lygus control program to help prevent the development of insecticide resistance.

Note Protect pollinating insects. See the supplement “How to Reduce Bee Poisoning from Pesticides,” in this handbook.

Pest Images