Download Dry Beans XIII - Wireworms

High Plains IPM Guide, a cooperative effort of the University of Wyoming, University of Nebraska, Colorado State University and
Montana State University.
Dry Beans XIII-2
Wireworms
Gary L. Hein & Frank B. Peairs
Wireworm larva.
Wireworm damage in dry beans is rare because when beans are emerging the soil surface
temperatures and moisture are not conducive to wireworm feeding.
Identification (and life cycle/seasonal history)
Wireworms are slender, yellowish, hard-bodied larvae that may grow to an inch or more
in length. Adult beetles are attracted to grasses to lay their eggs during mid-summer.
Therefore, rotations that include sod, cereals or grassy weeds are more likely to be
affected by this insect. Several species of wireworms may occur in this region, and their
life cycle may range from 2 to 5 years extending the potential for damage. Wireworms
begin to feed in the spring when soil temperatures rise above about 50oF. They move
deeper in the soil and cause less damage when the soil surface dries and soil surface
temperatures rise in early summer.
Plant Response and Damage
Wireworms are attracted to the carbon dioxide given off by germinating seeds and
seedlings. They tunnel into the seed, feed on roots, and may also feed on the stem just
above the seed. Damaged areas in the field will show up as spotty areas with reduced
stands. Later feeding on the stem may result in stunted or wilted plants and may predispose these plants to seedling diseases.
Management Approaches
Wireworm damage to dry beans is not common because beans in the region are planted in
late May or June and soil temperatures allow for rapid germination and establishment of
the bean plant. Several management options should be followed to reduce the risk for
damage by these insects:
1. plant when conditions allow rapid emergence of seedlings,
2. use seed treatments when planting in a high risk field; such as,
- fields with recent history of wireworm damage,
- fields previously cropped to sod, cereals or with extensive grassy weed
problems within the last 1 to 3 years,
3. monitor previous crops for presence of wireworms or wireworm damage.
High Plains IPM Guide, a cooperative effort of the University of Wyoming, University of Nebraska, Colorado State University and
Montana State University.
High Plains IPM Guide, a cooperative effort of the University of Wyoming, University of Nebraska, Colorado State University and
Montana State University.
Product List for Wireworms
Insecticide
Product
Seed Treatment
Preharvest Interval , remarks
Cruiser 5FS
See treatment directions and
1.28 fl oz/100 lb seed
precautions on label.
Gaucho 480
2-4 fl oz/100 lb seed
See treatment directions and
precautions on label.
R
Restricted 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, Insects, Wireworms
Date: 04/24/2006
High Plains IPM Guide, a cooperative effort of the University of Wyoming, University of Nebraska, Colorado State University and
Montana State University.