Scouting: Spider mites are easy to monitor despite their small size. Shake plants vigorously over a pail or bucket and then look for the tiny moving dots; they look like specs of sand walking around in the bottom of your pail. Initial infestations can be spotty, so it is important to check several places near the edge of the field. Spider mites are often found in potatoes near dusty roads or mite-harboring crops like alfalfa, corn, mint, or wheat.
Control: In many cases, a single, well-timed application will control spider mites. If you can see webbing on the leaves and bronzing or stippling from mite feeding, then it may be too late to get effective control with one application. Most miticide products target eggs and immature stages.
| Stage of Development: Tuber Bulking | ||||||
|---|---|---|---|---|---|---|
| Pesticide | MOA1 | Efficacy2 | Rate per Acre3 | REI4 | PHI5 | Notes |
| Movento HL spirotetramat | 23 | F | 2.0-2.5 fl oz | 24 h | 7 d | Movento HL is not recommended as a rescue treatment for spider mites, but it may delay or prevent mite outbreaks when it’s applied to control other pests. Do not apply after Oberon (another Group 23) unless an application of an insecticide with a different mode of action is used first. |
| Agri-Mek SC abamectin | 6 | G-F | 1.75-3.5 fl oz | 12 h | 14 d | Apply when mites are first detected. |
| Onager, Onager Optek hexythiazox | 10A | G | 16 to 24 fl oz | 12 h | 21 d | Apply at the first sign of mites i.e., apply early in the outbreak cycle. Controls mites via activity on eggs and immatures; it will not control adults, but they won’t lay viable eggs. |
| Oberon 4SC spiromesifen | 23 | E-G | 4-8 oz | 12 h | 7 d | Apply at the first sign of mites before adult populations build up. Controls all mite stages, but juveniles are more susceptible. |
| Comite proparagite | 12C | G | 32 to 40 fl oz | 2 d | 14 d | Apply when spider mites are present. Comite has a REI of 2 days, which is long compared to other miticides. |
| Acramite 4SC bifenazate | 20 | E-G | 16 to 24 fl oz | 12 h | 14 d | Apply when spider mites are present. |
| Minecto Pro abamectin, cyantraniprole | 6, 28 | G-F | 5.5 to 10 fl oz | 12 h | 14 d | Apply when mites first appear. Repeat the application after 7+ days if needed to maintain control. |
| Miteus fenpyroximate | 21A | E | 2 pt | 12 h | 7 d | Apply before mite populations begin to build. Controls all life stages, also stops feeding and egg laying. |
| BioCover MLT mineral oil/petroleum distillate | NC | ND | See Label | 4 h | Apply when spider mites first appear. | |
| Trilogy neem oil | NC | ND | See Label | 4 h | 0 d | Apply when mites first appear. |
1Mode of action. NC = not classified..
2 Efficacy ratings denote the relative ability of a pesticide to control its target. The ratings are E = excellent, G = good, F = fair/suppression; P = poor, and ND = no data. Efficacy ratings are based on the inherent toxicity of the pesticide against its target, the likelihood that the target will contact or ingest the product as applied, duration of impact on the target, and undesired effects, such as negative impacts on natural enemies that could lead to future pest outbreaks.
3 Rate per acre per application. Refer to the product label for maximum use rate per season.
4 Reentry interval.
5The minimum pre-harvest interval. Some products do not list PHI.
Note: always read and follow the directions on the pesticide label.
| Stage of Development: Late Tuber Bulking to Harvest | ||||||
|---|---|---|---|---|---|---|
| Pesticide | MOA1 | Efficacy2 | Rate per Acre3 | REI4 | PHI5 | Notes |
| Agri-Mek SC abamectin | 6 | G-F | 1.75-3.5 fl oz | 12 h | 14 d | Apply when mites are first detected. |
| Athena abamectin (avermectin) and bifenthrin | 3, 6 | G-F | 10-17 fl oz | 12 h | 21 d | Apply when mites are first detected, but only if it’s about 4 weeks to vine kill or harvest. |
| Onager, Onager Optek hexythiazox | 10A | G | 16 to 24 fl oz | 12 h | 21 d | Apply at the first sign of mites i.e., apply early in the outbreak cycle. Controls mites via activity on eggs and immatures; it will not control adults, but they won’t lay viable eggs. |
| Oberon 4SC spiromesifen | 23 | E-G | 4-8 oz | 12 h | 7 d | Apply at the first sign of mites before adult populations build up. Controls all mite stages, but juveniles are more susceptible. |
| Comite proparagite | 12C | G | 32 to 40 fl oz | 2 d | 14 d | Apply when spider mites are present. Comite has a REI of 2 days, which is long compared to other miticides. |
| Acramite 4SC bifenazate | 20 | E-G | 16 to 24 fl oz | 12 h | 14 d | Apply when spider mites are present. |
| Minecto Pro abamectin, cyantraniprole | 6, 28 | G-F | 5.5 to 10 fl oz | 12 h | 14 d | Apply when mites first appear. Repeat the application after 7+ days if needed to maintain control. |
| Miteus fenpyroximate | 21A | E | 2 pt | 12 h | 7 d | Apply before mite populations begin to build. Controls all life stages, also stops feeding and egg laying. |
| BioCover MLT mineral oil/petroleum distillate | NC | ND | See Label | 4 h | Apply when spider mites first appear. | |
| Trilogy neem oil | NC | ND | See Label | 4 h | 0 d | Apply when mites first appear. |
1Mode of action. NC = not classified..
2 Efficacy ratings denote the relative ability of a pesticide to control its target. The ratings are E = excellent, G = good, F = fair/suppression; P = poor, and ND = no data. Efficacy ratings are based on the inherent toxicity of the pesticide against its target, the likelihood that the target will contact or ingest the product as applied, duration of impact on the target, and undesired effects, such as negative impacts on natural enemies that could lead to future pest outbreaks.
3 Rate per acre per application. Refer to the product label for maximum use rate per season.
4 Reentry interval.
5The minimum pre-harvest interval. Some products do not list PHI.
Note: always read and follow the directions on the pesticide label.
