by Robin Stanback

A drive down scenic Old Frankfort Pike in Central Kentucky is all it takes to see firsthand the effects of last year's record-setting drought. The corridor, lined with historically important horse farms and a few that do not share the glory of a storied past, displays many green pastures that are not as lush as they have been in the past— despite a rainy spring in 2008.

Some pastures show the signs of careful stewardship but still lack the green patina that shouts, "Health food for horses!" Other fields look slightly parched, eaten down a bit too short by hungry animals, and some display the snaggle-toothed appearance of a variety of weeds.

Drought recovery does not happen overnight on even the most carefully tended properties. It often takes a series of seasons and dedicated managers who use every available resource to return fields to top form. Fortunately, the best possible time to make a real difference is right around the corner, and farm managers have a new source of help to make the most of it.

The University of Kentucky has launched a Pasture Management Program, part of the university's Equine Initiative, which is designed to help farm managers maximize their soils and existing pastures. In its third full year of operation, the program sends trained agricultural professionals to participating farms to identify and evaluate the percentage of grasses and weeds in their pastures.

The evaluation also includes a report on the pasture's levels of ergovaline. This toxic byproduct of the fungal endophyte present on some fescue grasses has been linked to late-term equine abortions and red-bag deliveries. This year, the program includes an optional pilot study of ascarid egg contamination as well.

"This program was developed during the fall of 2005," said Ray Smith, Ph.D., UK's forage extension specialist. "We evaluated pastures on 14 Central Kentucky farms focusing on the percentage of tall fescue that could present a toxicity problem for broodmares. The program was well received, and its success has led to an expanded form of evaluation."

This year, assessments will be performed from April through October. Farms that apply to the program receive an initial consultation followed by a sampling analysis of its pasture soils and grasses. After the assessment is completed, specialists provide a detailed description that provides a wide array of information about the tested paddocks.

Of primary importance to many horsemen is the percentage of tall fescue infected with the fungal endophyte. The farm report will contain information on the concentrations of ergovaline and an estimate of how much of the substance a horse grazing in that paddock is likely to ingest. Other grasses and weeds also will be identified.

Soil map of farm

Photographs of the property, including satellite images and a global-positioning map, are offered as an aid in monitoring improvements in the pastures. A comprehensive soil map of the entire farm comes along with recommendations for the number of horses per acre that can successfully be grazed on the land. The soil maps that are provided can be shared with county extension agents, who will help to develop detailed plans for targeting areas that might need extra fertilizer or lime.

"Another valuable aspect of this program is that farm owners and managers can ask questions directly of the people who have tested and analyzed their paddocks," Smith said. "They can discuss weed control, grazing management, and pasture renovation and reestablishment. Their questions can be answered immediately, and they can work together to design a program that best fits that particular farm."

Considering all the information the program offers, Smith said the cost is a bargain. The basic evaluation package, covering six paddocks or 80 acres, costs $750. Additional acreage can be added to the package at $10 per acre. A follow-up reevaluation of ergovaline measurements costs $75 for every field tested.

During a field day held at the University of Kentucky's Spindletop Farm, some of the agricultural professionals who are a part of the program were on hand to discuss different aspects of it. One of the more pressing problems facing horse farm owners right now is the reestablishment of paddocks and fields damaged by the drought.

The first step in that process is to test the soil and develop a program to bring it to optimal standards, both to feed existing grasses and to support germination and growth of new grasses. Next, the type and concentration of grasses and weeds should be determined to allow the farm manager to decide what type of weed control can best limit plants that might compete with the new grasses being planted. That program may consist of proper mowing strategies, or it may call for specific herbicides that will kill broadleaf plants. One serious consideration is the eradication of fescue tainted by the fungal endophyte that causes so many problems for broodmares.

Smith and his colleagues led field-day participants through a session of grass identification similar to that done by the pasture evaluation teams. Large rectangular areas of grass were sectioned off for study. Pointing out the differences between the grasses, Smith explained, "Orchardgrass is light green, and flattened at the base. Fescue is round with stiff, dark green leaves that are rough. The edges of the leaves are sharp. Bluegrass has a dark green, very slender blade with tips shaped like a boat's bow. Then there are the weeds to examine as well. We look for the concentrations of grasses and weeds and the types that are present in each field."

Cool-season grass

"Kentucky 31 tall fescue is one of the most abundant cool-season grasses in Kentucky," said graduate student Jennifer Johnson. "It is estimated that, of the eight-million acres of Kentucky pastures, 5.5-million have this fescue in them. It has lots of advantages—it is persistent, hardy, and drought-resistant.

"However, some of those very desirable things can be attributed to the endophyte within the plant. Horse owners can control the effects of ergovaline by removing mares from the pastures that contain high levels of the toxin two to three months prior to foaling. Or, farm owners can try to limit the amount of Kentucky 31 tall fescue in their pastures."

Smith emphasized the advantages of the evaluation program. It provides an assessment of the percentage of tall fescue plants infected with the endophyte and the concentration of ergovaline available to the horses grazing on that pasture.

"There are many options that can be discussed, from limiting the spread of the existing fescue [mowing the pasture to keep the fescue from being able to develop seed heads and reseeding the pasture with other more desirable grasses] to renovating the entire pasture by killing off all the grasses and starting from scratch," he said.

The most drastic method of ridding a pasture of undesirable plants is to kill the existing vegetation with herbicides and start over. Less severe is the use of herbicides that target specific types of weeds and grasses. If this method is used, the herbicide should be sprayed when the vegetation is actively growing but, depending upon the chemicals used, at least a couple weeks before reseeding the area with grass.

"Fall is when you need to reseed pastures if you are using cool-season grasses like bluegrass, orchardgrass, and tall fescue," said Steve Higgins, Ph.D., agriculture research specialist at UK.

Higgins explained the futility of planting seed at any other time. "Sure, you can plant grass seed in the spring. It may even come up and start looking good, but then the summer heat and dry weather will kill off your progress. The very best time to plant seeds is from August 15 to early October. The earlier in that time frame, the better. You might think, 'August? It is too dry in August,' but once the seed is in the ground and we get those late summer showers, it gets the seeds growing and then the cool weather of fall helps them along."

Recommendations

The pasture evaluation program package includes recommendations on the types of grass seeds that will do best on the tested pastures. Based upon the university's research trials and those done in neighboring states, the grasses that are suggested will be those that perform well in the region's climate and soil quality. In Central, Eastern, and Northern Kentucky, bluegrass is popular for its ability to withstand close grazing and hoof traffic. It also forms a tight sod.

Two other types of grasses that do well in those areas are orchardgrass and endophyte-free tall fescue.

"Not all fescue grasses are infected with the endophyte like Kentucky 31, but not all of them have the same hardy nature that holds up well in horse pastures," Smith said. "We are researching different types of endophyte-free fescue and trying to develop one that will have all the properties we want, without the worry of ergovaline."

Another grass that is getting attention from Kentucky horsemen is bermudagrass, a hardy turf grass that is low-growing and palatable to horses. It also holds up very well to droughts and hoof traffic. When some of the cooler-season grasses are wilting in the summer sun, bermudagrass will do very well. The leaves are blue-green, small, and linear, with rough edges. This type of grass, however, is best established with a spring planting rather than in the early fall.

Once the seed type is determined, University of Kentucky's experts recommend purchasing high-quality seeds that are free of contamination from other seed crops and weeds. These seeds will usually have high rates of germination. Getting them into the ground where they can flourish is up to the farm owner and his or her budget.

The most effective and expensive method of seeding is to till the seeds into freshly worked topsoil. This requires that the pasture be rested until such time as the grasses are established.

Because many horse owners probably will be planting the seeds in already-established pastures, no-till planting or broadcast seeding might be used effectively. The advantage to no-till planting, in which a machine is used to put the grass seeds at specific depths (a quarter-inch to a half-inch for most of the grasses discussed), is that the grass seed gets directly into the soil.

Broadcast seeding, sometimes referred to as frost seeding, is not as reliable. While horses and other livestock can be depended upon to walk some of the seeds in to the required depth, not all of the seeds will get that benefit.

Managing pastures and reseeding where horses continue to graze can be a challenge. It becomes especially trying when rain makes mud pits out of areas where horses like to congregate. Part of the pasture evaluation program involves recommendations for grazing management. The evaluation team will look at available paddocks and help the farm owner determine the best possible grazing rotation to optimize the forage available to the farm's horses.

Finally, the program provides a CD-ROM with all the information the experts have gathered on the farm along with their recommendations. The disc becomes a working electronic version of a pasture and paddock action log. "Farm owners can use this to chart their farm's progress," Smith said. "They can easily share the information with their county extension agent and with the people who may be providing services such as fertilizing and seeding."

Click here for more information about UK's horse pasture evaluation program. 

Robin Stanback is a freelance writer based in Versailles, Kentucky