Nothing is harder on grass than constantly being grazed down to the roots, and horses are notorious overgrazers. Grass needs to be rested occasionally to allow it to rejuvenate. This pasture management method, called rotational grazing, offers your pastures their best chance at rejuvenation. Rotational grazing also helps keep weeds at bay and combats soil compaction by promoting root growth.
Rotational grazing requires that all animals be removed from a pasture when the grass is grazed below two inches. The pasture then sits empty until the grass has grown above six inches. For a rotational grazing system to work, though, you must be able to rest each pasture up to a month at a time. Larger pastures should be subdivided as much as possible to encourage the horses to graze the grass more evenly than they would normally. The smaller your pastures, the more intensively you'll need to manage them.
An example of temporary fencing that can be used to section off larger pastures. Note that the corner metal stakes are capped. Solar power is used to charge the fence tape. Temporary fences should always be contained inside permanent fencing (Image right).
But a rotational grazing plan involves more than just moving horses from pasture to pasture. To get the most out of your land, follow these steps:
Have your soil analyzed to determine its fertility level and pH, and have the pastures limed and fertilized accordingly.
Have your fields aerated, if possible, once a year. Seed bare areas each fall.
Determine how many times you can subdivide each pasture. There is no magic number when it comes to horses. You'll need to take into account the activity level of each herd, and how quietly they interact. For instance, a sedate herd of geldings can be squeezed into a smaller space than can a group of youngsters or a mixed-sex group. You don't want the horses to feel too crowded or they can become aggressive toward each other. If you're not sure how much crowding your horses will tolerate, start slow by subdividing a large pasture once. Test that for a couple of weeks, and if all goes well, try subdividing it again.
Designate one of the subdivisions as a sacrifice area-a pasture or paddock that you sacrifice for the sake of the other pastures. You'll put the horses in the sacrifice area whenever the ground is wet or if none of your pastures has regrown to more than six inches. A sacrifice area should be on the best-drained part of your land and as far from a stream or low area as possible. A sacrifice area's surface can be anything that won't wash away, from grass (or earth) to bluestone to wood chips.
Subdivide your pastures. Because you may need to move the interior fencing, it should be portable, such as horse tape and step-in posts. For highest visibility, use at least two strands of wide, white tape.
Start your horses in the pasture that is in the best shape. Monitor the grass length, and move the horses when the majority of grass has been grazed down to 2 to 3 inches in height. The amount of time spent in each pasture will vary depending on the time of year.
Each time you move the horses, drag the newly vacated pasture to break up and spread out manure.
Move the horses once the grass gets short. If the next pasture hasn't regrown to six inches, put the horses in the sacrifice area until the pasture is ready.
Occasionally clip the pastures no shorter than six inches to prevent weeds from going to seed and to keep the grass palatable, which promotes even grazing.
Using a soil probe to take a soil sample on farm near Iowa City, IA (Image right) . Source: Photo courtesy of USDA Natural Resources Conservation Service
Note: Soil samples should be taken every three years to monitor pasture fertility and nutrient content of the soil. For more information on how to prepare a soil sample and interpret the soil test results, go to the MSU Soil and Plant Laboratory home page.
Rotational grazing allows your pastures to stay green, which is healthier for your pastures and your horses. As a bonus, you should see a decrease in your feed bill as well. For more information on horse manure management and other soil conservation and water quality practices, contact you local Soil Conservation District.
Possible Grazing Rotation and Use of a Sacrifice Area
When to Use a Sacrifice Area:
The grass has not had adequate time to re-grow to a height that it has adequate food reserves stored to tolerate grazing again. (As in this example.)
You are short on pasture acres and you limit grazing time each day which will extend the number of days the animals can use the pasture.
You have wet field conditions and putting animals out on the pasture will compact the soil and damage the grass in the pasture for the rest of the season.
You are in a drought and grazing below minimum recommended heights will kill the grass. Total reestablishment costs and the value of future lost grazing production exceeds the costs of purchasing hay in a drought or other pasture related shortfall.
For more information contact your local Soil Conservation District/ Natural Resources Conservation Service/ (SCD/ NRCS) office or county Maryland Cooperative Extension (MCE) office. The Horse Outreach Workgroup was established to provide information to horse owners on pasture and manure management issues. Technical assistance is available from local county Soil Conservation Districts/Natural Resource Conservation Service and the Maryland Cooperative Extension office. The workgroup consists of representatives from local Soil Conservation Districts, Maryland Department of Agriculture, Natural Resource Conservation Service, Cooperative Extension, University of Maryland, the Equiery, and the Maryland Horse Council. The Maryland Department of Agriculture’s Office of Resource Conservation provides coordination for the workgroup. January 2001, revised January 2007
Equine Facilities: Pasture and Paddock Area Requirements. 2011. eXtension.org/horses article.
Equine Pasture Management. 2012. eXtension.org/horses Learning Lesson.
Grazing Systems for Horses. Robert A. Mowrey. 2009.
Planning a Horse Pasture. Krishona Martinson. 2009.
Pasture Management for Horse Acreages Webcast. 2009. Dave Freeman for My Horse University and eXtension.org/horses.