I wanted to provide a quick reference chart for common pests in cotton and recommended treatment thresholds. I hope a condensed chart will be useful and save time. Please refer to the Georgia Pest Management Handbook for cotton insecticide options or call our office at 263-4103 or my cell phone @ 305-7047.
| PEST | THRESHOLD |
| Aphid (Cotton) | Apply when aphids are abundant and seedling leaves are severely curled, or when “honeydew” is present in older cotton. |
| Beet Armyworm | Apply when 10% of squares are damaged, 10% of blooms are infested, or when 10 active “hits” are observed per 300 row feet. |
| Bollworm/Tobacco Budworm | Apply insecticide on Bt cotton when 8 larvae (1/4 inch or greater in length) are found per 100 plantsOn non-Bt cotton apply when 8 small larvae are found per 100 terminals prior to first insecticide treatment, or when 5 larvae are found after first spray. |
| Cutworm | Apply when stand is threatened. Spot treatment is often adequate. |
| Plant Bugs/Flea Hoppers | Apply when plants are retaining less than 80% of pinhead squares and numerous plant bugs are observed. |
| Soybean Looper | Treatment is necessary when soybean loopers threaten to defoliate cotton with immature bolls. |
| Spider Mites | Apply when mites are spreading. Spot treatment may be adequate. |
| Stink Bugs | Use a 10-15% boll injury threshold during weeks 3-5 of bloom, 20% during weeks 2 and 6 and 30%(+) during weeks 7(+) of bloom. Detection of 1 stink bug per 6 row feet would also justify treatment. |
| Thrips | Apply when 2-3 thrips per plant are counted and immatures are present. |
| Whitefly (banded winged) | Apply when 50% of terminals in rapidly growing cotton are infested, or when honeydew is found on foliage or lint of older cotton with open bolls. |
| Whitefly (silverleaf) | Silverleaf whitefly is difficult to control with insecticides. Early detection and conservation of natural controls are important. |
