–by Jeff Whitworth — Field Crops
“Worms” (larvae of armyworms, fall armyworms, etc.) are still causing considerable concern, at least throughout the eastern 2/3rd’s of Kansas. They have slowed a little over the last couple of weeks, as many have been pupating, mating, egg laying, etc. Therefore, if you have experienced significant “worm” activity in the last month or two, it will be a great time to start monitoring those vulnerable areas, i.e. seeding wheat, brome, alfalfa, etc. to detect any new “worm” infestations while the worms are small before they can do much feeding. The picture on the left is a brome field in Saline County that had a significant infestation of armyworms and was sprayed approximately 2 weeks prior to this picture and there was no rain between spraying and the date of this picture. The picture on the right is a patch of that same pasture that could not be sprayed.
(Pictures provided by a rancher in Saline Co.)
Also, we have conducted 2 separate insecticide efficacy trials against armyworms, one in brome and one in volunteer wheat. The raw data from the trial in brome are presented here. Analyzed results of both trials will be available on the KSU Entomology website, hopefully, in the near future.
| Total worms/ft2/4 Reps | |||
| Treatment | Rate | 19 Sept (7 dat) | 26 Sept (14 dat) |
| Fastac CS | 2.4 fl. oz/a | 0 | 1 |
| Besiege XL | 8.0 fl. oz/a | 0 | 2 |
| Stallion | 6.0 fl. oz/a | 0 | 2 |
| Grizzly Z | 2.5 fl. oz/a | 0 | 0 |
| Lorsban 4E | 1.5 pint/a | 3 | 3 |
| Check (control) | – | 25 | 26 |
| Check (control) | – | 18 | 20 |