Pasture improvement

This page is outdated—from when I was on the faculty at Iowa State University.  I’ll update with Georgia specific content eventually...but the general principles are the same....

Pastures are ideally suited to Iowa. For those of you not familiar with the state, you may be surprised to know that most of Iowa is not flat. If you make a big "U" in Iowa around the west, south, and east sides of the state, you will see considerable amounts of land that look somewhat like the picture below, and are ideally suited to be permanent pastures.

If you head north from from Des Moines to Minneapolis on I-35, you will be in the middle of the "U" and the land is generally, though not exclusively, flat. Even on this flat land, pastures can be very profitable, although in general these pastures are typically planted with high production species, like alfalfa and orchardgrass, and grown in rotation with corn and soybeans.

My interests are in developing varieties of various species that will be adapted to Iowa pasture conditions--both permanent and rotational pastures.

Grazing tolerance
I have had a long-time interest in grazing tolerance, dating back to my time on my family's farm and as a graduate student with Joe Bouton at the University of Georgia. At ISU, we have done quite a bit of work evaluating alfalfa and other species under intense continuous grazing--see Brummer & Moore, 2000 and the Iowa Crop Performance annual alfalfa trial bulletins. We evaluate under the worst possible conditions for insurance: if entries survive this, they will survive on anyone's farm. But we don't recommend doing this at home! In addition to evaluation, we have selected some reed canarygrass and smooth bromegrass plants for survival under these conditions. We are currently evaluating this material to see if it has enhanced grazing tolerance.

Putting cattle on grazing trials, mid-May

After about 1 month of grazing.

After four months of continuous grazing.

Germplasm collections from old pastures
Several years ago, Steve Barnhart, ISU Extension Forage Specialist, and I received a small grant from the Leopold Center for Sustainable Agriculture at ISU to collect orchardgrass and white clover plants from old pastures throughout the state. The collected plants were intercrossed to form an "Iowa Adapted" germplasm that is being used for further selection. Our hope was that selecting in pastures would give us plants that are adapted to the grazing management, climate, and soils of Iowa, and hence, that these materials might be useful to develop improved pasture varieties.

Steve and his golf cup cutter, looking for prime genotypes to collect in a northeast Iowa pasture

This is an example of the mixed pastures we were looking at--many different species growing in complex mixtures.

Steve points to an excellent orchardgrass genotype he just cut out of the pasture--this is one of about 250 orchardgrass plants we used to form our population.

A crossing block of orchardgrass, surrounded by a border of rye to help prevent pollen contamination.

The white clover population in the greenhouse at Ames.

Birdsfoot trefoil breeding
The major breeding effort I have with birdsfoot trefoil is improving the persistence, grazing tolerance, and biomass production of rhizomatous trefoil germplasm. A few years ago, Paul Beuselinck, USDA-ARS, Columbia, MO, released a germplasm, ARS-2620 that expressed rhizomes. We are attempting to select superior genotypes from this population for an eventual variety release. Our first efforts to do this failed when the most vigorous individuals we selected were winter killed. We are trying again to get this population developed. Note that in its infinite wisdom, USDA-ARS transferred Paul Beuselinck to work on soybeans! He was the only full-time trefoil scientist in the US. Missouri has many soybean scientists. Makes you wonder.

A sprawling rhizomatous trefoil plant (single plant).

Its roots, showing the large rhizomes (white), expressing in the late autumn.

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