PEST MANAGEMENT DECISION GUIDE: GREEN LIST
Fall armyworm on wheat
- Avoid late or off-season planting and avoid planting new crop near infested fields
- Avoid staggered planting (planting at different dates in the same field), as this provides a continous source of food for the pest
- Use short maturing and less preferred wheat varieties to escape the pest infestation that might occur later in the season
- Ensure optimum use of fertilizer for wheat plants to be able to compensate for damage done and apply at the right time
- Conserve shelters and flowering plants on the edges for beneficial insects such as ground beetles and parasitoids
- Destruction of volunteer wheat and weedy grasses in ditches around field margins can eliminate these sources of armyworms
- Rapid disposal of wheat residues after harvest
- After germination of seedlings, scout fields, at 5 or more spots, weekly (starting from the field margin) for larvae on plants and whether the problem is widespread or confined to certain areas or edges.
- Caterpillars: light green to dark brown with longitudinal stripes. Dark head with an upside down pale Y-shaped marking on the front. The second-to-last body segment has four dark spots forming a square (3rd instar and above)
- Look for leaves that seem to have had all of their green tissue removed which gives the leaf a "window pane" appearance. Examine some plants showing evidence of injury, and look for small caterpillars. The suggested treatment threshold is 2-3 larvae per linear foot of row in wheat with active feeding symptoms.
- Fall armyworm larvae feed primarily during the night and during cloudy weather. During the day, look for armyworms under loose soil and fallen leaves on the ground.
- Use a pheromone with the Universal Bucket Trap to estimate adult moth population
- If available, spray young caterpillars with neem-based products before they move to neigbouring plants
- Use microbial biopesticides based on bacteria, fungi and viruses if available
CREATED/UPDATED: April 2018
PRODUCED BY: Plantwise
©CAB International. Published under a CC-BY-SA 4.0 licence.