New herbicides - All about Spartan, Valor and Roundup
April 15, 2004
The North Dakota Department of Agriculture, Valent and IR-4 are all working together to get Valor labeled as a dry bean desiccant. Residue trials will be conducted this summer and Section 18 registration may be possible in 2005, depending on the fall weather.
NDSU trials have shown that Valor is faster and more effective than Roundup as a dry bean desiccant and doesnt cause blemishes on the seed as do some other products. It also costs less than Roundup, $3.50 to $4 per acre depending upon the adjuvant used, compared to $6 for Roundup.
Glyphosate label very likely
Glyphosate registration on dry bean as a preharvest application is slated for review at the EPA at this present time, making registration this year likely. Growers must realize that glyphosate will be labeled for weed desiccation, not dry bean desiccation, in physiologically mature dry beans. The label will restrict applications before dry beans are mature. Valor will be for dry bean desiccation, glyphosate for weed desiccation prior to harvest.
Spartan is a new pre-emergence herbicide labeled in dry beans. A non-ALS inhibitor, Spartan is a good rotation choice if ALS resistance is becoming a problem for you. Spartan controls lambsquarter, nightshade, pigweed, smartweed, kochia, Russian thistle and biennial wormwood. It suppresses foxtail, wild mustard, wild buckwheat, common ragweed and others. Cost is $3.50 to $10 per acre, depending upon rate.
Spartan performance and crop safety can be affected dramatically by soil pH and organic matter. The solubility of Spartan increase as pH increase making it more active in high pH soils. However, organic matter safens the Spartan on dry beans in high pH soils. At the North Central Research Station, Minot, N.D., researchers saw as much as 50% damage in low organic matter, high pH soil plots. In high organic matter, high pH soils in the eastern Dakotas, excellent dry bean safety was observed.
Here are some guides:
· The finer the soil type, the safer.
· The more organic matter, the safer.
· The lower soil pH, the safer.
· Requires 0.5 to 0.75 inches of rain to work.
· Pre-emergence application is preferred than pre-plant incorporated application.
If you have used Pursuit and/or Raptor eight to nine times in dry beans and other crops in the rotation, you are approaching a level where resistant populations may develop. This is especially true for eastern black nightshade. Use non-ALS herbicides in the rotation to prevent resistance from becoming a problem.
In dry beans, Pursuit and Prowl are good options if you are battling wild buckwheat. Wild buckwheat is showing up more and more in row crops due to weather the past few years, increase in row crops, and increase in the use of glyphosate (Roundup). It is slightly tolerant to Roundup, and once the plant begins to vine, tolerance to glyphosate increases, allowing the weed to escape.
Reflex is a good choice for nightshade control in dry beans. Reflex is likely to get a Section 18 label again. North Dakota is applying for a Section 18 for the whole state, not just east of highway 281. Make sure to use a high rate of water per acre to get the coverage needed for good control.