Dry Beans XIII-12

Spider Mites

Gary L. Hein & Frank B. Peairs

Two-spotted spider mite.

Identification (and life cycle/seasonal history)

The two-spotted spider mite is a minute arthropod found in colonies under webbing on the lower surface of leaves. Infestations are often associated with drought stress and hot, dry weather conditions.

Plant Response and Damage

Damaged leaves will have a silvery or bronzed look.  Little is known about the effect of spider mite feeding on dry bean yield and quality, but the earlier in crop development that infestation starts, the more likely it is that significant losses can occur. 

Management Approaches

Infestations are rare in the region with the possible exception of western Colorado.  Damage is most often seen in dry years adjacent to areas of broadleaf weeds that have been cut down or severely stressed.  Chemical control of spider mites is difficult and seldom recommended.

 

 

Products for Spider Mites:

Insecticide

Product

Preharvest Interval , remarks

Di-Syston 15%R,       8R

15%: 6.0 oz./1000 ft            8: 0.9-1.9 oz./1000 ft

PHI 60 days; REI 72 hrs.            

dimethoate1

multiple formulations

See label for rates.

PHI see label; REI 48 hrs.

Kelthane MF

1-3 pt/A

PHI 21 days; REI 12 hrs.

Temik 15GR

 

7.0-14.0 lbs./A 

Apply at planting. Potential for groundwater contamination.  See label for environmental precautions and restrictions.  PHI 90 days; REI 48 hrs. 

Thimet 20GR                         

4.5-7.0 oz/1000 row ft

Apply at planting; drill to side of seed, not in contact with seed; PHI 60 days; REI 72 hrs.

RRestricted use pesticide 1Labeled for chemigation

The information herein is supplied with the understanding that no discrimination is intended and that listing of commercial products, necessary to this guide, implies no endorsement by the authors or the Extension Services of Nebraska, Colorado, Wyoming or Montana.  Criticism of products or equipment not listed in neither implied nor intended.  Due to constantly changing labels, laws and regulations, the Extension Services can assume no liability for the suggested use of chemicals contained herein.  Pesticides must be applied legally complying with all label directions and precautions on the pesticide container and any supplemental labeling and rules of state and federal pesticide regulatory agencies.  State rules and regulations and special pesticide use allowances may vary from state to state:  contact you State Department of Agriculture for the rules, regulations and allowances applicable in your state and locality. 

 

 

Categories:  Dry Beans, Spider Mites

 

Date: 04/24/2006