Description of the Pest
Flea beetle adults are small, ranging in size from 0.06 to 0.12 inch (1.5 to 3 mm) long. These insects derive their name from their well-developed hind legs; when disturbed they jump like fleas.
Damage
Adult beetles chew small holes in leaves, giving them a sievelike appearance. The small, slender, white larvae feed on underground parts of the plant. On rare occasions, flea beetles may feed directly on ripe fruit, just below the calyx. This damage is usually seen only in late-season plantings that show extreme foliar stress resulting from lack of water or powdery mildew.
Management
Eliminate plant stress from insufficient moisture and powdery mildew.
Start monitoring after transplanting or when seedlings emerge. During stand establishment flea beetles can damage seedlings and may require an insecticide application. If field monitoring at the time of ripening shows feeding signs on fruit, base treatment decisions on the severity of damage.
| Common name | Amount per acre | REI‡ | PHI‡ | |
|---|---|---|---|---|
| (Example trade name) | (hours) | (days) | ||
| Not all registered pesticides are listed. The following are ranked with the pesticides having the greatest IPM value listed first—the most effective and least harmful to natural enemies, honey bees, and the environment are at the top of the table. When choosing a pesticide, consider information relating to air and water quality, resistance management, and the pesticide's properties and application timing. Always read the label of the product being used. | ||||
| A. | ACETAMIPRID | |||
| (Assail 30SG) | 2.5–5.3 oz | 12 | 0 | |
| (Assail 70WP) | 1.1–2.3 oz | 12 | 0 | |
| MODE-OF-ACTION GROUP NUMBER1: 4A | ||||
| B. | CLOTHIANIDIN | |||
| (Belay) | 9–12 oz | 12 | 21 | |
| MODE-OF-ACTION GROUP NUMBER1: 4A | ||||
| COMMENTS: Review and follow the California neonicotinoid regulations effective January 1, 2024. Permissible application rates may be lower and application timing may be restricted if using managed pollinators, applying more than one neonicotinoid active ingredient, or using more than one application method in the same season. | ||||
| C. | CARBARYL* | |||
| (Sevin XLR Plus) | 1 qt | 12 | 3 | |
| MODE-OF-ACTION GROUP NUMBER1: 1A | ||||
| COMMENTS: Observe plant response precautions listed on label. Avoid excessive applications. | ||||
| D. | LAMBDA CYHALOTHRIN | |||
| (Warrior II with Zeon) | 1.28–1.92 fl oz | 24 | 1 | |
| MODE-OF-ACTION GROUP NUMBER1: 3A | ||||
| E. | METHOMYL* | |||
| (Lannate SP) | 0.5–1 lb | 48 | See comments | |
| (Lannate LV) | 1.5–3 pt | 48 | See comments | |
| MODE-OF-ACTION GROUP NUMBER1: 1A | ||||
| COMMENTS: Labeled for use on cucumbers, melons, and summer squash. Highly toxic to bees. PHI is 1 day when 0.5 lb or less for 90SP or 1.5 pt or less for LV formulations is used; when more than 0.5 lb (90SP) or 1.5 pt (LV) is used, PHI is 3 days. | ||||
| F. | CRYOLITE | |||
| (Prokil Cryolite 96) | 10–16 lb | 12 | See comments | |
| MODE-OF-ACTION GROUP NUMBER1: UN | ||||
| COMMENTS: Labeled for use on cantaloupe, squash, and watermelon. Applied as a spray. Thorough coverage using ground equipment is necessary for adequate control. Do not apply immediately before harvest. Remove excess residues on edible portions by washing, brushing, or other effective means. Effectiveness of this material is lower than materials listed above. PHI is 7 days for summer squash and 14 days for winter squash, cantaloupe, and watermelon. | ||||
| G. | PYRETHRIN# | |||
| (PyGanic EC 1.4) | 16–64 oz | 12 | 0 | |
| MODE-OF-ACTION GROUP NUMBER1: 3A | ||||
| COMMENTS: Buffer final spray to a pH of 5.5 to 7.0. | ||||
| ‡ | Restricted entry interval (REI) is the number of hours (unless otherwise noted) from treatment until the treated area can be safely entered without protective clothing. Preharvest interval (PHI) is the number of days from treatment to harvest. In some cases the REI exceeds the PHI. The longer of two intervals is the minimum time that must elapse before harvest. |
| 1 | Rotate chemicals with a different mode-of-action group number, and do not use products with the same mode-of-action group number more than twice per season to help prevent the development of resistance. For example, the organophosphates have a group number of 1B; chemicals with a 1B group number should be alternated with chemicals that have a group number other than 1B. Mode-of-action group numbers (un = unknown or uncertain mode of action) are assigned by IRAC (Insecticide Resistance Action Committee). |
| * | Permit required from county agricultural commissioner for purchase or use. |
| # | Acceptable for organically grown produce. |