Colaspis Beetles in Soybean
Crop Injury: Colaspis beetles (Colaspis spp.) are found in most soybean production areas of the U.S. Grape colaspis (Colaspis brunnea) is most common, but other colaspis species such as Iowa colaspis (Colaspis crinicornis) are found in some soybean production areas. Most economic injury is from larvae feeding on roots of plants soon after planting. Corn and rice are more vulnerable to root feeding than soybean. Damage often occurs in patches and can be confused with damage from nematodes and other cryptic root feeders. Adults are defoliators of soybean but are seldom numerous enough to cause economic levels of defoliation by themselves.
Pest Description: Adult beetles are clay-orange in color and are from 1/8 to 3/16 inch long. They have parallel tan lines on their forewings. The larvae are small, white grubs with visible legs and are up to 1/4 inch in length.
Colaspis beetle on soybean.
Brandon Kleinke
Colaspis beetle adult.
Daren Mueller
Life Cycle: Colaspis beetles overwinter as small larvae in the soil. In the spring, larvae feed on roots, sometimes causing economic damage to young plants of many species. Following pupation, adults emerge from the soil in mid-summer. Adults feed on a wide variety of crops, but seldom cause economic damage. Mating and egg-laying occurs within two weeks after emergence, and eggs take one to two weeks to hatch. Larvae feed on roots in the fall before overwintering begins again. One generation occurs each year throughout North America.
Scouting: Scouting is not generally recommended for colaspis beetle because the damage is caused by the larvae in the soil and there are no rescue treatments available after planting. Digging in the soil around plants to look for larvae can confirm an infestation. Using a sweep net after adult emergence in mid-summer can be used to select management options for the following year, but no thresholds are established. Dry soil conditions can exacerbate grape colaspis beetle injury.
Management: Economic injury from this pest is rare in most regions. When planting in fields with a history of colaspis beetle larval injury, use an insecticidal seed treatment and good agronomic practices to ensure that early plant root growth is vigorous. Crop rotations with cotton or rice may reduce damage to soybean, but corn is a suitable crop for colaspis beetle oviposition, so rotation between soybean and corn has not been shown to reduce populations.
Developed and reviewed by Fred Musser, Mississippi State University; Erin Hodgson, Iowa State University; and the Iowa State University Integrated Pest Management Program.
Colaspis beetle on soybean.
Colaspis beetle.
Gallery images courtesy Brandon Kleinke and Daren Mueller.
This publication was developed by the Crop Protection Network, a multi-state and international collaboration of university/provincial extension specialists and public/ private professionals that provides unbiased, research-based information to farmers and agricultural personnel. This information in this publication is only a guide, and the authors assume no liability for practices implemented based on this information. Reference to products in this publication is not intended to be an endorsement to the exclusion of others that may be similar. Individuals using such products assume responsibility for their use in accordance with current directions of the manufacturer.
In accordance with Federal civil rights law and U.S. Department of Agriculture (USDA) civil rights regulations and policies, the USDA, its Agencies, offices, and employees, and institutions participating in or administering USDA programs are prohibited from discriminating based on race, color, national origin, religion, sex, disability, age, marital status, family/parental status, income derived from a public assistance program, political beliefs, or reprisal or retaliation for prior civil rights activity, in any program or activity conducted or funded by USDA (not all bases apply to all programs). Remedies and complaint filing deadlines vary by program or incident.
Persons with disabilities who require alternative means of communication for program information (e.g., Braille, large print, audiotape, American Sign Language, etc.) should contact the State or local Agency that administers the program or contact USDA through the Telecommunications Relay Service at 711 (voice and TTY). Additionally, program information may be made available in languages other than English.
To file a program discrimination complaint, complete the USDA Program Discrimination Complaint Form, AD-3027, found online at How to File a Program Discrimination Complaint and at any USDA office or write a letter addressed to USDA and provide in the letter all of the information requested in the form. To request a copy of the complaint form, call (866) 632-9992. Submit your completed form or letter to USDA by: (1) mail: U.S. Department of Agriculture, Office of the Assistant Secretary for Civil Rights, 1400 Independence Avenue, SW, Mail Stop 9410, Washington, D.C. 20250-9410; (2) fax: (202) 690-7442; or (3) email: program.intake@usda.gov.
This work is supported by the Crop Protection and Pest Management Extension Implementation Program from the U.S. Department of Agriculture’s National Institute of Food and Agriculture. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and should not be construed to represent any official USDA or U.S. Government determination or policy.
USDA is an equal opportunity provider, employer, and lender.
©2025 by the Crop Protection Network. All rights reserved.
