IFAS Extension
Recommended Chemical Controls for Root Weevils
READ THE LABEL.
Rates for pesticides are given as the maximum amount required to treat mature citrus trees unless otherwise noted. To treat smaller trees with commercial application equipment including handguns, mix the per-acre rate for mature trees in 250 gal of water. Calibrate and arrange nozzles to deliver thorough distribution and treat as many acres as this volume of spray allows.
Table 1. Recommended chemical and biological controls for citrus root weevils.
|
IRAC MOA1 |
Pesticide Trade Name |
Rate/Acre2 |
Comments |
Pests Controlled |
|---|---|---|---|---|
|
Parasitic Nematodes | ||||
|
NR |
Nemasys® R |
|
| |
|
Nemasys® R |
18,000–40,000 nematodes or greater per square foot |
Nemasys® R contains live nematodes to reduce Diaprepes and Pachnaeus spp. subterranean stages. Make 1 or more applications per year when soil temperatures exceed 70°F. Apply through microirrigation or through herbicide boom to moist soil; 0.5–1 inch irrigation is needed after application. |
Root weevils | |
|
Note: Nematode products that have been tested and recommended by UF/IFAS are currently unavailable. | ||||
|
Soil Barrier | ||||
|
3 |
Bifenthrin |
|
| |
|
Brigade WSB |
0.25–0.5 lb a.i. |
Restricted use pesticide. Apply uniformly to moist, weed-free soil. Do not apply via irrigation. Do not exceed 32 oz/acre per season. |
Root weevils, fire ants, Asian cockroach | |
|
Foliar Spray | ||||
|
1A |
Carbaryl |
|
| |
|
Sevin 4 F + Petroleum Oil 97+% (FC 435-66, FC 455-88, or 470 oil) |
1–2 gal + 1 gal oil |
Contact/residual foliar spray. Lower rates will result in reduced residual activity. Do not exceed 20 lb a.i./acre/year for all uses. Do not exceed 2 applications per season. May increase spider mite populations. Do not apply when temperature exceeds 94°F. 470 weight oil has not been evaluated for effects on fruit coloring or ripening. Heavier oils are more likely to be phytotoxic than lighter oils. |
Root weevils, orange dog, katydids, grasshoppers, crickets, scale | |
|
Sevin XLR + Petroleum Oil 97+% (FC 435-66, FC 455-88, or 470 oil) |
1–2 gal + 1 gal oil | |||
|
1B |
Phosmet |
|
| |
|
Imidan 70 WP |
1–2 lb |
Contact foliar spray. |
Root weevils | |
|
3 |
Fenpropathrin |
|
| |
|
Danitol 2.4 EC |
16–21 oz |
*Restricted use pesticide. Contact foliar spray. Do not apply when temperatures exceed 94°F. |
Root weevils, thrips, citrus psyllid | |
|
15 |
Diflubenzuron |
|
| |
|
Micromite 80 WGS + Petroleum oil 97+% (FC 435-66, FC 455-88, or 470 oil) |
6.25 oz + 1 gal oil |
*Restricted use pesticide. Residual foliar spray. Maximum of 3 applications per season. Do not apply when temperature exceeds 94°F. 470 weight oil has not been evaluated for effects on fruit coloring or ripening. Heavier oils are more likely to be phytotoxic than lighter oils. Do not combine with Boron within 21 days to harvest. |
Root weevils, citrus leafminer, citrus rust mites | |
|
1 Mode of action class for citrus pesticides from the Insecticide Resistance Action Committee (IRAC) Mode of Action Classification v. 11.4 (2025). 2 Lower rates may be used on smaller trees. Do not use less than the minimum label rate. | ||||
