Volume 20, No. 1

MARYLAND WEED REPORTER

By now, most of you should have received a new copy of Extension Bulletin 237, Pest Management Recommendations for Field Crops. The spiral binding was a hit the past 2 years so we decided to keep on using it. While we are selling hard copies of this bulletin, we are also making it available on the web. At first, it will be somewhat difficult to navigate. You will have to download large sections. Printing may also be a problem. However, we are working on making it more user friendly in the future. The $19.00/copy price is steep. Because they shut down Ag. Duplicating, we had to use University Press and their costs are sky high. Steve Rothman is looking into alternative printers for next year.

Most of the following changes have been added to EB 237. With the rapid growth of Roundup-Ready soybeans, there isn't much growth in the soybean market as far as herbicides are concerned. Most of the growth is in corn and other agronomic and horticultural crops.

Last year, Syngenta introduced Lumax, a new package-mix product for use in corn. It contains a mixture of Dual II Magnum + atrazine + Callisto. While you get sufficient Dual II Magnum and Callisto in the package-mix, there generally isn't enough atrazine to provide season-long control of large-seeded broadleaf weeds like morningglory and cocklebur. Therefore, it is suggested that you add an additional 1 to 1 ½ pints of atrazine per acre to improve your overall broadleaf weed control.

Due to the fact that there is not enough atrazine in the current Lumax formulation, Syngenta will be introducing a new Lumax (yet unnamed) formulation in 2005. The following table gives you the breakdown of what's contained in Bicep II Magnum, the current Lumax formulation and the proposed Lumax formulation for 2005.

Not everyone wants to use a preemergence herbicide in their corn production system. Whether you're growing Roundup-Ready corn or regular field corn, there are a number of options available. DuPont had the market share for early postemergence weed control in corn with a product called Basis Gold. However, they are phasing out this product and introducing two new package-mixes, called Steadfast and Steadfast ATZ. The following table shows you the breakdown of the products contained in each.

You'll notice that the rate of Accent is insufficient when treating perennial grasses such as johnsongrass. Thus, additional Accent will be required under those situations.

For those of you that use Roundup or Touchdown in your farming operation, we are also seeing changes in formulations. Last year, Monsanto introduced Roundup Weather Max, while Syngenta had Touchdown IQ. This year, Syngenta will be introducing a new glyphosate formulation called Touchdown Total. The following table summarizes the similarities between the two manufacturers and their glyphosate containing products.

BASF will gradually be phasing out the current formulation of Prowl and replacing it with Prowl H20. This formulation will be more water soluble, less volatile and have minimal odor as compared to the EC formulation. Plant corn at least 1.5 inches deep and completely cover with soil. Rates will run from 2.0 to 4.0 pints/acre.

Monsanto will be reintroducing Lasso for the soybean market under the trade name INTRRO. The RR in INTRRO stands for Roundup-Ready soybeans. Their goal is to introduce cheap alachlor for those growers that want a preemergence herbicide up-front where they plant Roundup-Ready soybeans. Rates will run from 2.0 to 3.0 quarts/acre. This particular formulation is not labeled for corn, but is labeled for sorghum.

BASF has finally received a label for the use of Distinct on noncropland, pasture, hay and rangeland. This "new" product will be trade named Overdrive. Use rates range from 4.0 to 8.0 ounces/acre in pasture, hay and rangeland. On noncropland, a maximum of 10 ounces/acre can be applied. What is unique about this registration as compared to Banvel or Clarity is the grazing restriction. The label states, "pasture and rangeland grass treated with Overdrive can be grazed or harvested for livestock feed immediately after application." For noncropland, the label states, "do not enter treated areas without protective clothing until sprays have dried."

I just received word that Osprey 4.5WDG from Bayer CropScience has been registered by the EPA for postemergence control of Italian ryegrass control in wheat. Registration may be pending in Maryland until Bayer solicits a state label. Use rate will be 4.75 ounces/acre. As for rotational restrictions, soybeans may be planted 90 days after application, while corn may be planted 12 months after application. Most other crops can be safely planted after 10 months.

Thought I'd get this out in a timely fashion since the growing season is around the corner!