Farming
Alabama is currently experiencing a widespread outbreak of fall armyworms with an exceptionally high numbers of caterpillars. It is expected that this forage pest will continue to hang around until the first frost. While fall armyworms can defoliate a field quickly, they rarely kill healthy stands of grass.
Alabama Extension professionals are still getting a lot of questions about what products can control fall armyworms in pastures, especially given the lack of availability in some areas. The following information summarizes the products that Alabama producers can apply and details how the products work, their residual levels, and any grazing/harvest restrictions.
Table 1. Insecticides for Pasture Control of Fall Armyworms
Always use pesticides according to label directions.
Trade names are used only to give specific information. The Alabama Cooperative Extension System does not endorse or guarantee any product and does not recommend one product instead of another that might be similar.
| Active Ingredient | Product Example | How it Works | Residual Level* | Grazing and Harvest Intervals | Notes |
|---|---|---|---|---|---|
| Beta-cyfluthrin | Baythroid XL | Contact or ingestion of treated material; starves to death | Low | Grazing: 0 days Harvest: 0 days | Good coverage is necessary; rapid knockdown |
| Cyfluthrin | Tombstone | Contact or ingestion of treated material; starves to death | Low | Grazing: 0 days Harvest: 0 days | Good coverage is necessary; rapid knockdown |
| Gamma-cyhalothrin | Declare | Contact or ingestion of treated material; starves to death | Low | Grazing: 0 days Harvest: 7 days | Good coverage is necessary; rapid knockdown |
| Zeta-cypermethrin | Mustang Maxx | Contact or ingestion of treated material; starves to death | Low | Grazing: 0 days Harvest: 0 days | Good coverage is necessary; rapid knockdown |
| Diflubenzuron | Dimilin 2L | Ingestion of treated material; dies after unsuccessful molt | Medium | Grazing: not specified Harvest: 1 day | Only works on small, less than 1-inch worms; may take a few days to see results |
| Methoxyfenozide | Intrepid 2F | Ingestion of treated material; dies after unsuccessful molt | Medium | Grazing: 0 days Harvest: 0 days | Only works on small, less than 1-inch worms; may take a few days to see results |
| Spinosad | Blackhawk | Contact or ingestion of treated material; starves to death | Low | Grazing: 0 days Harvest: 3 days | Good coverage is necessary; rapid knockdown |
| Methomyl | Lannate LV2.4 | Contact or ingestion of treated material; dies from respiratory failure | Low | Grazing: 7 days Harvest: 3 days | Good coverage is necessary; rapid knockdown |
| Carbaryl | Sevin XLR Plus | Contact or ingestion of treated material; dies from respiratory failure | Medium | Grazing: 14 days Harvest: 14 days | Good coverage is necessary; rapid knockdown |
| Chlorantraniliprole | Prevathon | Ingestion of treated material; stops feeding | High | Grazing: 0 days Harvest: 0 days | Feeding stops right away; death takes 24 to 72 hours |
| Lamba-cyhalothrin + Chlorantraniliprole | Beseige | Contact + ingestion of treated material; starves to death | High | Grazing: 0 days Harvest: 7 days | Rapid knockdown plus long residual |
For more information about fall armyworm control, contact the Alabama Extension animal sciences and forages regional agent that serves your area.