Bean, snap-Lygus bug

Lygus spp.

Pest description, crop damage and life history

See:

Pest monitoring Use sweep nets to sample for lygus bugs. In the Pacific Northwest, a suggested treatment threshold is one-half adult or one-half for fourth or fifth instar per sweep. In California, for dry beans, treatment thresholds vary depending on the variety and the stage of the crop, from one-half to two lygus bugs per sweep.

Management-biological control

Generalist predators, such as lacewings and damsel bugs, may prey on lygus bug nymphs. Conserve populations of these biological control agents by minimizing applications of broad-spectrum insecticides.

Management-cultural control

Lygus are likely to move when other food sources become unsuitable. Common weeds that are good hosts of lygus bugs include pigweed and wild radish.

Mowed alfalfa fields nearby are commonly a source of large numbers of lygus bug adults. There are a number of practices to reduce or control the movement of adults from alfalfa into nearby bean fields. These techniques leave uncut, tall alfalfa (which is attractive to lygus bug adults) within or near the cut area.

Management-chemical control: HOME USE

Follow information given on the label about the timing and cutoff date for the particular vegetable you are spraying.

  • azadirachtin (neem oil)-Some formulations are OMRI-listed for organic use.
  • Beauvaria bassiana-OMRI-listed for organic use.
  • bifenthrin
  • carbaryl
  • esfenvalerate
  • gamma-cyhalothrin
  • kaolin-Applied as a spray to foliage and stems it acts as a repellant to some insect pests. Some formulations are OMRI-listed for organic use.
  • malathion
  • plant essential oils (garlic, rosemary, etc.)-Some have demonstrated efficacy. Some formulations are OMRI-listed for organic use.
  • pyrethrins (often combined with other ingredients)-Some formulations are OMRI-listed for organic use.
  • zeta-cypermethrin

Management-chemical control: COMMERCIAL USE

  • bifenthrin (Sniper) at 0.08 to 0.1 lb ai/a. PHI 3 days. REI 12 hr. Do not exceed 0.2 lb ai/a per year.
  • borate complex (Prev-Am Ultra) applied as a 0.4% to 0.8% solution. Spray to complete coverage. PHI (see label). REI 12 hr. Retreatment interval 4 days. OMRI-listed for organic use.
  • carbaryl (Sevin 4F) at 1.5 lb ai/a. PHI 3. REI 12 hr. Do not exceed 6 lb ai/a per crop. Retreatment interval 7 days. Toxic in aquatic habitats. Latex-based formulations, such as Sevin XLR Plus, are less hazardous to bees. Do not apply carbaryl dust to blooming weeds because of severe hazard to pollinating bees.
  • chlorantraniliprole/lambda-cyhalothrin (Besiege) at 0.06 to 0.1 lb ai/a. PHI 7 days. REI 24 hr. Retreatment interval 5 days. Do not exceed a total of 31.0 fl oz of Besiege or 0.12 lb ai of products containing lambda-cyhalothrin or 0.2 lb ai of chlorantraniliprole per acre per growing season. Do not graze livestock or harvest vines for forage or hay.
  • dimethoate (Cheminova Dimethoate 4E) at 0.5 lb ai/a. PHI 0 days. REI 48 hr. Retreatment interval 14 days. Do not exceed 1.0 lb/a per year. Do not feed treated vines.
  • Isaria fumosorosea (PFR-97 20%WDG) at 1 to 2 lb product per acre. PHI 0 days. REI 4 hr. Repeat every 3 to 10 days as needed. OMRI-listed for organic use.
  • lambda-cyhalothrin (Warrior II) at 0.02 to 0.03 lb ai/a. PHI 7 days. REI 24 hr. Retreatment interval 5 days. Do not exceed 0.12 lb ai/a per year. Do not graze livestock in treated areas or harvest vines for forage or hay.
  • methomyl (Lannate SP) at 0.45 to 0.9 lb ai/a. PHI 1 to 3 days for beans, 3 days for feeding vines, 7 days for hay. REI 48 hr. Do not exceed 4.5 lb ai/a per year.
  • naled (Dibrom) at 0.94 lb ai/a. PHI 1 day. REI 48 hr. Retreatment interval 7 days. Do not exceed 5 treatments per season.
  • phorate (Thimet 20G)-Do not exceed 1.5 lb ai/a. PHI 60 days. REI 48 to 72 hr. At planting time only. Do not graze or feed to livestock. Toxic to fish and wildlife.
  • sulfoxaflor (Transform) at 0.047 to 0.071 lb ai/a. PHI7 days. REI 24 hr. Retreatment interval 14 days. Do not exceed two consecutive applications per crop. Do not exceed 0.266 lb ai/a per year.

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