More recent crops and forage questions and answers

Crops and forage

Ragweed control

Over the past few years I have leased about 50 acres of pasture on the family farm. I noticed that the pasture that was once fescue and clover has become overgrown with ragweed. What would you recommend as a control for the ragweed? Could its pressence be a by-product of overgrazing?

Common ragweed is often a problem in pastures. Infestations can certainly be accentuated by overgrazing, but it is an opportunistic weed that can infest a variety of environments. It is fairly easy to control. Grazon P+D at 2 pints per acre will be one of the most effective and economical options for this weed, giving greater than 90 percent control. This product (as all pasture herbicides do) will also kill your legumes.

Kevin W. Bradley
Division of Plant Sciences

Feeding fescue with seedheads

I have fed fescue hay for the past 12 years. I never had any problems with toxicity because the custom hay baler was always at my place last. This caused the seed heads to be totally dropped off and the undergrowth was all that was available. This year however, all the neighbors were frozen out and had to wait for the roots to revive the plants, but my fescue came on strong and was the first available for baling. Will this hay be higher in toxcisity because the plant was in the milk stage?

I raise miniature herefords and miniature horses. The herefords will be eating this hay exclusively this winter with protein supplements.

The pregnant horses will be in dry lot on small bales of brome. The others will have the fescue. What is your recommendations as to feeding this hay starting in about January?

Yes, your hay with seedheads will be significantly more toxic than your hay without seedheads. My recommendation about feeding it would be to give it to the cattle only and to supplement the hay; supplementation could include corn or a by-product, such as distiller's grain, soy hulls, corn gluten, etc. This hay should not be fed to pregnant mares.

Craig Roberts
State forage specialist

Tests for endophyte

I've been told that once you convert a pasture or hay field from K31 to MaxQ that there is no test that can be performed in future years to determine if K31 is taking over, all endophytes will test the same. Is this accurate?

The main two tests for the KY31 endophyte and the MaxQ endophyte involve the microscope or a chemical test (antibodies). They both test for presence, not concentration, of endophyte. The microscopic test cannot distinguish between these endophytes. Also, the general chemical test cannot distinguish between them.

There may be a special test that may be available now; I am not sure. If so, it would be a chemical test (ELISA) specific for AR542, which is the MaxQ endophyte strain. Again, I do not know if such a test is available. And even if it were, it would be available to the company, AgResearch of New Zealand. The developer would be Dr. Nick Hill at the University of Georgia.

Also, there would be a test that could be used for court cases. It would be expensive and not feasible for farmers. It would be a DNA test. The main scientist running such a test would be Dr. Chris Schardl at the University of Kentucky.

And lastly, there is an indirect test that measures endophyte compounds, such as ergot alkaloids. The scientists running these tests would include Dr. Morrie Craig (Oregon State University), Dr. George Rottinghaus (University of Missouri), Dr. Ali Mubarak (University of Arkansas), all of whom run a straight chemistry test. Dr. Hill also tests for endophyte compounds with ELISA, though this test can pick up true ergot products (that are not endophyte compounds).

Craig Roberts
State forage specialist

Grass for waterlogged pasture

I am planting some pasture in a wet area for my cattle. What grass do you recommend?

The ideal grass would be reed canarygrass. It is slow to establish but persistent for many years in waterlogged soils. If you plant this grass, be sure to get a variety that produces low concentrations of alkaloids. Such varieties might be Venture or Palaton. Be sure to work with your local extension agronomist and refer to G4649, Reed Canarygrass, Ryegrass, and Garrison Creeping Foxtail.

Craig Roberts
State forage specialist

Endophyte infection test

How can I have my hay and pasture tested for fescue grass that may have the endophyte infection?

The most consistent and rapid testing is by immunochemistry. I would contact the technicians at Agrinostics.

Craig Roberts
State forage specialist

More crops and forage questions and answers

Updated 5/21/08