Below are the results of a spider mite trial sprayed last week in Gibson County (40 PSI, 10 GPA, FF80015). Ratings were taken 4 and 7 days after application. Note that Athena, a pre-mix of abamectin and bifenthrin (Brigade), was used at less than the recommended rate of 10-17 per acre. However, 8 oz/acre of Athena provides the same rate of abamectin as in 6 oz of Agri-Mek. Athena at 8 oz also includes bifenthrin at an equivalent rate as 3 oz of Brigade.
All treatments provided statistically significant control compared with the untreated plots. Oberon (4 or 8 oz/acre) was the best treatment followed by Zeal (0.75 oz/acre), Liberty (29 oz/acre), and Agri-Mek (6 oz/acre). Brigade, as usual for this time of season, did not perform well.
Many are using Agri-Mek or one of the other abamectin products because the price is right. I don’t disagree, but keep in mind that two applications at a 5-7 day interval are often necessary when dealing with increasing populations of spider mites. Two applications will almost always do better than one application at a higher rate.
| Product and Rate per Acre | 4 DAT | 7 DAT |
| Athena (8 oz) | 75.8 bc | 47.8 bc |
| Brigade 2E (6.4 oz) | 97.8 b | 60.0 b |
| Agri-Mek 0.15 EC (6 oz) | 70.0 bcd | 28.0 cd |
| Zeal 0.72 WG (0.75 oz) | 44.5 def | 22.8 cde |
| Oberon 4SC (4 oz) | 23.0 f | 9.5 e |
| Portal 0.4E (16 oz) | 60.8 cde | 47.5 bc |
| Oberon 4SC (8 oz) | 37.3 ef | 17.5 de |
| Liberty 280SL (29 oz) | 39.3 ef | 24.8 cde |
| Untreated | 196.8 a | 105.3 a |
Means followed by same letter do not significantly differ (P=0.05, LSD).
