by Cynthia McFarland

With spring just around the corner, the growing season is nearly upon us.

In some parts of the country, this means horses that have spent limited time outdoors during the harshest months of winter will soon be enjoying more hours outside. In milder regions, horses do not need to be stabled through the winter, but dormant pasture grasses afford reduced nutritional value, depending on their maturity level at dormancy.

To give your pastures the best opportunity for healthy growth well into summer, specialists in four different regions of the country were interviewed to discover what farm owners and managers should be aware of now.

Kentucky

Kentucky farm owners typically have orchard grass and bluegrass as the primary pasture grasses. “There is also some fescue, although there has been a concentrated effort on some Thoroughbred farms to remove fescue,” said Bob Coleman, Ph.D., extension horse specialist at the University of Kentucky.

If you want to add seed to thicken the stand in orchard grass and bluegrass fields, this is typically done in late August or early September. “If we get good environmental conditions, then it will start growing, but you have to keep horses off it,” Coleman said. “If you put out seed in the spring, you have to protect the pasture and not use it for grazing, ideally for a year, but for at least eight months to establish the pasture.”

While Coleman is looking ahead to this spring and summer with “guarded optimism,” he said Kentucky farm owners need to be prepared to implement a good weed- control program this year.

“Be aware that there’s the potential for weeds to be more aggressive this year, particularly if you have some areas in pastures that were overgrazed,” said Coleman. “Because of the drought we had, some pastures were stressed and ended up with some bare ground, and areas that were used as ‘sacrifice areas’ may be more weedy this year. Weeds always handle drought better than grass.”

Controlling and eliminating those weeds may require judicious use of herbicides. To be a good steward of the environment, Coleman urged farm owners to consult with their local cooperative extension agent on what herbicides to use and when. Some weeds can be targeted in early spring, while it is advisable to wait until later in the season for others. Your extension agent can help you identify weeds and advise on the best ways to control them without damaging the pasture.

If at all possible, incorporate a rotational grazing plan. “If you can move horses off pasture and let it rest for a minimum of three weeks, this will help give the stand of grass a chance to come back and re-establish root reserves,” Coleman said. “The more plant material you’re able to leave, the faster it will recover.”

Pull horses off when at least three to four inches of active plant material remain. If you want to top off the grass, Coleman recommends not mowing any lower than four inches.

In the Bluegrass region, Coleman recommends fertilizing in the fall, not spring. “Fertilizing stimulates the plant to grow, and if you do it in March when plants are actively growing, you end up with this huge, luxurious top growth that you may or may not be able to make use of. But if you fertilize in October or November [usually somewhere between Halloween and Thanksgiving], you will thicken up the stand of grass.”

With Chuck Dougherty, Ph.D., specialist in grassland management and utilization, Coleman has been involved in a University of Kentucky study on using Bermuda grass as summer pasture. The study is also intended to help horse owners come up with helpful grazing strategies.

“Up here, you need to select a winter-hardy variety of Bermuda grass, and there are a couple varieties available. We’re probably as far north as it’s going to work,” Coleman said. “I see it having a possible place in a rotational system, but it takes a lot of work, and you’re going to have to wait a year to use it for grazing. If you’re not prepared to manage it, you don’t want to do it. Bermuda will handle the summer slump when the cool-season grasses back off; Bermuda grass keeps on growing, and it takes a lot of abuse.”

A five-acre stand of Bermuda grass was established at the University of Kentucky facility and has been used extensively for the past two years. Electric tape was used to divide the pasture into five one-acre sections to allow rotational grazing from the end of May through mid-September. A group of Thoroughbred and Quarter Horse mares grazed on the Bermuda grass, and the group is rotated so that each one-acre field is grazed for a week and then rests for four weeks.

With this system, the horses involved in the study maintained their body weight without any other supplemental feed except salt and minerals, and the pasture maintained a good stand of grass.

Florida

February is a great time to take a soil sample in the south so you know what is needed when you fertilize in the spring once the rains start.

“If you haven’t taken a soil sample, you can take one now prior to fertilizing to find out if you have any deficiencies of a particular nutrient you need to adjust, and to find out if there are adequate amounts of nutrients that you won’t need to apply,” said Mark Shuffitt, University of Florida-IFAS Marion County extension agent in Ocala.

“Our grass doesn’t start growing and coming out of dormancy until the end of February, first of March,” Shuffitt said. “Usually, this is our time to fertilize. Now is not the time to overseed with Bahia grass seed because it needs soil temperatures up in the 70s, which usually doesn’t happen until May or June.”

Drought has affected pastures in Florida’s horse country, but the negative effects are most clearly seen in pastures that have not been managed properly. Shuffitt says a common problem is that people move to the area and overstock their horse pastures.

“You see a pasture that hasn’t been grazed and it has knee-deep grass in the middle of growing season, and someone moves here and puts 10 to 15 horses on a 10-acre field. Those horses eat the grass down, and when it goes dormant in the winter, it’s really hard on the pasture,” Shuffitt said.

“People want to know what to do in the middle of a crisis, but your best plan is to put yourself in a position that you’re not likely to get hurt by the drought,” he added. “Here with improved pasture, you should have at least two acres per horse. That way if you do run into drought, you have some margin, and you’re not against the wall with overstocking. You can prevent a lot of headaches based on what can happen outside your control weather-wise.”

Shuffitt notes that you can actually double your stocking rate if you carefully manage the amount of grazing allowed on a pasture. For example, if you have more horses than the stocking rate allows, do not provide 24-hour access to the pasture. Limit the hours in which horses are turned out to graze and, instead of relying primarily or completely on pasture, feed supplemental hay as needed to maintain healthy body condition.

New York

Horse owners in the Northeast region of the country are not dealing with the drought issues some other areas are facing.

“Right now, we’re above normal in both rainfall and snow, so we’re not looking at a drought. We’re looking pretty good,” said Debbie Cherney, Ph.D., associate professor of animal science at Cornell University in Ithaca, New York.

In fact, some pastures are so rich, due to excellent growing conditions, that horse owners should be aware of the possibility of founder.

“We’re starting to be a little concerned about pasture quality getting too good,” Cherney said. “We cannot keep white clover out of our pastures, so we’re starting to talk about things we can do, such as not over-liming because this encourages high pH, which encourages clover to come in. You certainly don’t want to plant legumes (such as clover) in pastures where you have horses that are subject to foundering. You may even want to feed some hay before turning these horses out. Grazing pastures heavily in the spring is a good idea to keep the growth down.”

In New York horse pastures, the number one grass is still timothy, but there is also a good deal of orchard grass and some types of fescue. The standard stocking rate is one acre per thousand-pound horse, but this varies widely depending of the type of pasture grass and how well it is managed.

Overseeding existing pastures at this time of year can be done, but with varying degrees of success. “It really depends on if we’re having a freeze and thaw period,” Cherney said. “If it freezes and thaws, the ground develops tracks and the seeds drop down into the ground. But if it just turns warm and doesn’t freeze again, we get a total failure because the seeds germinate, but they’re right on top of the ground so the young plant dies quickly.”

To boost pastures that need improvement, Cherney recommends doing a soil test and applying fertilizer in the spring based on the results, and then again during the summer.

Cherney suggested walking pastures regularly several times throughout each season to make sure weeds are not becoming a problem. Because weeds begin growing at different times, walking the pasture just once a season is not enough.

Walking the pasture is also important because you want to find any poisonous plants that spring up or spread over the fence where horses can reach them. Common poisonous plants in this area are yew, rhododendron bushes, maple trees, and wild cherry trees (both leaves and bark).

“We don’t recommend removing trees, but if a green branch falls off a tree, pick it up,” Cherney said. “We don’t have too many horse poisonings up here since horses will usually stay away from poisonous things unless feed is short.”

If you have any questions about identifying poisonous plants, contact your local cooperative extension agent. Most offices provide a booklet or brochure with drawings or photos of poisonous plants native to that area.

California

Pasture availability varies depending on the part of the state, with dirt-lot turnout being common in Southern California and actual grazing pastures found farther north. Managing those pastures can be challenging because of weather conditions and the number of horses grazing the pastures.

Horses at the Animal Science Horse Barn at the University of California-Davis are kept in dry-lot paddocks through the wet winter months to spare the pastures.

“We have very heavy rains from December through March, so none of our horses are on pasture right now because we get a lot of pasture damage when the ground is so wet,” explained Nicole Webster, manager of the Animal Science Horse Barn. “Horses are different from other livestock with cloven hooves because of their weight and one solid hoof. If the ground is damp, they can very easily cause serious damage to the pasture. Cattle aren’t as bad, but horses really tear it up.”

The UC-Davis facility maintains pastures that are heavy in orchard grass with some timothy, alfalfa, and a small amount of clover. “We reseed our pastures annually in late November with a pasture mix that contains all of these,” Webster said.

She adds annual reseeding most likely would not be necessary if pastures are not grazed intensively. Late fall is ideal for reseeding because the ground is typically not too wet, thus allowing agricultural equipment to be brought in to do the job, and the winter rains will benefit the newly seeded fields.

If you have kept horses in dry lots, or “sacrifice areas,” for the winter to protect pastures when the ground is wet, you must take care when turning horses back out on lush spring grass to guard against founder or colic problems.

Webster begins putting horses on pasture again about the end of March and does so gradually, starting with just a half-hour a day for the first two days. She then increases the time by one hour, so that horses are out for 11⁄2 hours on the third and fourth days. “We keep increasing the time by an hour until they’re out for eight hours a day, and then we just leave them out round the clock,” she said.

If you have cool season grasses, watch your stocking rates carefully because summer heat dramatically slows the growth of these grasses. “When you’re at 100° for more than a month, it causes a lot of damage,” Webster said. “The orchard grass and timothy doesn’t get a lot of growth in the hot weather.”

Once the grass backs off, the weeds tend to come on strong, so take proactive measures before weeds get the upper hand. “You’ll want to spray with herbicides before weeds go to seed because otherwise you’ll end up having to spray more and it will cost you more,” Webster said.

In Northern California pastures, mustard weed, star thistle, and curly dock can pose big problems if not treated aggressively. Webster has pastures sprayed in the winter and again in early summer, as necessary. Knocking weeds back early in the season will allow the grass to overtake them as the grass growth spurts ahead in spring.

Depending on your area, pasture turnout may provide more of a mental benefit for horses than nutritional. Webster adds that it is better for mares and foals to be out on pasture than in a small dry lot, even if they’re not getting a lot of nutritional value from the grass. Feed supplemental hay to keep horses in good condition when grass value drops due to stress from weather or overstocking.

Cynthia McFarland is a Florida-based Thoroughbred Times correspondent