POSTEMERGENCE FOXTAIL HERBICIDE CHOICES IN WHEAT
Postemergence herbicide choices for foxtail (pigeongrass) control in wheat include Achieve, Cheyenne, Dakota, Hoelon, Puma, Stampede, and Tiller. The following is a listing of herbicide application rates and timing for foxtail and wheat, approximate costs, and additional weeds controlled.
Application rate = 40 acres/box. Foxtail stage = 1- to 5-leaf stage. Wheat stage = 2-leaf to boot. Cost = $17/acre. Also controls wild oat.
Application rate = 40 acres/box. Green foxtail stage = 2-leaf to 2-tiller. Wheat stage (HRS or winter wheat only) = 3-leaf to end of tillering (6-leaf). Cost = $17/acre. Also controls wild oat and barnyardgrass, and numerous annual broadleaf weeds.
Application rate = 1 to 1.33 pt/acre. Green foxtail stage = 2-leaf to 2-tiller. Wheat stage (HRS or winter wheat only) = 3-leaf to end of tillering (6-leaf). Cost = $6/acre. Also controls numerous annual broadleaf weeds.
Application rate = 2 to 2.66 pt/acre. Foxtail stage = 1- to 4-leaf. Wheat stage = up to 4-leaf. Cost = $16-22/acre. Also controls wild oat.
Application rate = 0.33 pt/acre for green foxtail and 0.4 pt/acre for yellow foxtail. Foxtail stage = 2-leaf to 2-tiller. Wheat stage = 2-leaf to 6-leaf. Cost = $8.50 to 10/acre. Also controls volunteer corn and wild oat (at 0.67 pt/acre). Consult label for broadleaf herbicide tank mixture restrictions on grassy weed control.
* Stampede 80EDF + MCPA ester:
Application rate = 1.25 to 1.4 lb/acre + 0.5 pt/acre. Foxtail stage = 1- to 3-leaf. Wheat stage = 2- to 4-5 leaf . Cost = $5.50 to 6.50/acre. Also controls selected annual broadleaf weeds.
Application rate = 1 pt/acre for green foxtail and 1.2 pt/acre for yellow foxtail. Foxtail stage = 2-leaf to 2-tiller. Wheat stage (HRS or winter wheat only) = 3- to 4-leaf up to 6-leaf. Cost = $9-11/acre. Also controls wild oat (at 1.7 pt/acre) volunteer corn and several annual broadleaf weeds.
Refer to herbicide labels and NDSU Extension Service circular W-253 "2000 North Dakota Weed Control Guide" for required information on use and other details including tank mixtures.
FLEA BEETLES IN CANOLA
As most canola has emerged in the region, it is important to be monitoring for flea beetle and associated injury to the crop. Canola fields should be frequently checked (daily) from plant emergence to at least the stage when the first two true leaves are fully expanded. If beetle populations are high and the crop is slowly developing, field scouting may need to continue into the 3- to 4-leaf stage. Cool, moist weather conditions favor canola development and reduce beetle activity.
The treatment threshold for flea beetle is when canola injury is approaching 25% and beetles continue to be present in the field. Insecticides labeled for postemergence treatment of flea beetles include: Capture, endosulfan (Endocide 3 EC or Thiodan 3 EC), ethyl-methyl parathion 6-3, and methyl parathion 8EC. Capture recently received a reduced rate label allowing use of 1.3 to 2.1 fl oz/acre for flea beetle control. See insecticide labels for required information. Foliar treatments must be made quickly to stop an accelerated level of injury. Residual control is limited to a few days, providing the potential for reinfestation of the insect.