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I. Corn
Status is a herbicide from BASF that contains the same active ingredients as Distinct (dicamba + diflufenzopyr), but also contains the safener isoxadifen. Unlike Distinct, this will allow Status to be applied postemergence to corn from 4 to 36 inches in height without drop nozzles. Status can be applied with a nonionic surfactant, crop oil concentrate, or methylated seed oil. In our trials, we observed no differences in weed control between postemergence applications of Status and Distinct. The remaining stocks of Distinct will be sold out and Status will essentially replace Distinct over time.

Autumn is a new herbicide from Bayer CropSciences that is available for use as a fall-applied herbicide prior to corn planting. Autumn can also be applied up to 30 days before corn planting in the spring. Autumn is not labeled for use on areas that will be planted to soybeans. Autumn is an ALS-inhibiting herbicide which contains the active ingredient iodosulfuron. It should be applied at a rate of 0.3 oz/A. Autumn should be applied with a crop oil concentrate at 1% v/v and a nitrogen fertilizer. In our research with Autumn last year, we observed good control of henbit and common chickweed with fall applications of Autumn or Autumn plus 2, 4-D. Similar levels of henbit and chickweed control were also achieved with Basis plus 2, 4-D and Princep plus 2, 4-D. The addition of 2, 4- D increased control of annual fleabane and corn speedwell compared to applications of Autumn alone. Although we have not evaluated these weeds in our trials, other university researchers have also observed good field pennycress, shepherd'spurse, purple deadnettle, marestail, and dandelion control with applications of Autumn plus 2, 4-D in the fall.

Impact (topramezone) was first available for use last year, but will be discussed briefly as many are still unfamiliar with this product. Impact is a new herbicide from AMVAC that is a HPPD-inhibiting "bleacher" herbicide like Callisto. Impact can be applied postemergence in corn at either 0.5 or 0.75 fluid ounces per acre. In our trials conducted last year, Impact provided similar levels of broadleaf weed control as Callisto, but slightly higher levels of grass control. Both products are enhanced significantly by the addition of atrazine.

Stout is a new premix from DuPont that contains nicosulfuron (Accent) and thifensulfuron (Harmony GT) and is registered for use primarily for grass weed control in corn. Stout may be applied at ½ to ¾ ounce per acre to corn that is up to 16" tall and exhibiting up to and including 5 leaf collars.

II. Soybean
Prefix CP is a new co-pack from Syngenta that contains S-metolachlor (Dual II Magnum) and fomesafen (Reflex or Flexstar). Later in 2007, it is expected that this product will become a premix (both ingredients mixed in one bottle) but at least initially in 2007 this will be sold as a co-pack where one package contains one bottle of S-metolachlor (which actually has Prefix on the label) and one bottle of Reflex. The typical use rate of this product will deliver 1 pint per acre of Dual II Magnum and 1 pint per acre of Reflex. Prefix CP is labeled for preemergence weed control in soybeans and in our trials during the past year, this product has performed similar to Boundary, which is the product from Syngenta that this herbicide will replace.

Sonic and Authority First are identical products from Dow AgroSciences and FMC, respectively. They both contain the active ingredients sulfentrazone (Spartan) and cloransulam (Firstrate) and are registered for use preemergence in soybean at planting or within three days of soybean planting. These products should provide good control of a wide spectrum of broadleaf weeds including waterhemp, lambsquarter, moningglory, ragweeds, cocklebur, and others.

Canopy is now being marketed and sold again from DuPont for preemergence weed control in soybeans. Canopy can also be applied as a burndown product, or as part of a burndown program in no-tillage systems. This is the Canopy formulation that contains chlorimuron (Classic) plus metribuzin (Sencor). Remember that Canopy EX is another product from DuPont that contains chlorimuron (Classic) plus tribenuron (Express), and is primarily utilized for winter annual weed control in the fall-applied market. Canopy may be applied at planting or up to 45 days before planting and provides residual control of a number of small-seeded grass and broadleaf weeds.

III. Wheat
Axial is a new herbicide from Syngenta for use in wheat for the control of winter annual grass weeds like wild oat and annual or Italian ryegrass. However, Axial does not provide control of cheat or downy brome, which are two of our most common winter annual grasses encountered in wheat production in Missouri. Axial (pinoxaden) is labeled for use at 8.2 ounces per acre and should be applied with the Adigor adjuvant at 9.6 ounces per acre.

IV. Grass Pastures and Hay
Remedy Ultra and Garlon 4 Ultra are both new products from Dow AgroSciences that will be replacing the old products Remedy and Garlon 4 in the pasture market. All of these products have triclopyr as the single active ingredient. The difference in the new "Ultra" formulations is that these will contain methylated seed oil rather than kerosene as the solvent or carrier. Additionally, the "Ultra" formulations are low-odor compared to the older formulations. We have not seen or heard of any significant differences in weed control as a result of this new formulation.

Kevin Bradley,
573-882-4039