Creating Good Pasture for Your Horse

Proper pasture management can make a significant difference in yield and allow your horse to graze more, in turn, consuming less supplemental hay. As a general rule, horses will graze 0.26 lbs of dry matter per 220 lbs of body weight per hour. If your horse is 1000 lbs and grazes for ~16 hours this equates to 19 lbs of dry matter in pasture. If we add in the moisture to the weight calculation, it ends up being just shy of 80 lbs of pasture consumed per 24-hour period. Now, most horse owners do not have the luxury of being able to graze their horse on pasture 24/7 all summer. Therefore, this blog post is going to touch on the key aspects of plant management that can improve your pasture.

Let’s begin by discussing the 5 key management tasks.

1)      Mowing

Over a 24-hour period, the horse will graze for a total of ~16 hours. Unfortunately, they do not graze evenly. Horses are selective and will over-graze some areas, while leaving other areas to over-grow. Since horses like shorter, newly growing pasture – mowing is a handy management tool.

It is recommended to never mow below 3 inches. The plant requires this height and leaves to be able to absorb sunlight and continue to grow. Therefore, by regularly mowing your pasture after horses have been rotated off it you can ensure you are creating even growth to promote more even grazing. The pasture will be ready to graze again when it is at least 6 inches tall.

2)      Rotation

Rotating your pastures is another key management tactic. Grazing is extremely stressful on pasture, therefore, ensuring you plan for rotation can increase the yield and general health of your pasture. It is recommended that you should have at least 3 paddocks. One dry lot area, and a minimum of two pasture areas to be able to correctly rotate. Moving the horses to new pasture area will allow the pasture they just grazed to recover.

3)      Manure Management

Manure piles will kill plants. Dragging or picking your paddocks to ensure the manure piles are being broken up is important to avoid dead areas where the horses defecate. It is recommended that you drag or harrow the paddock on hot and dry days to kill parasite larvae.

4)      Weed Control

When weeds outcompete the grass, your pasture can take a turn for the worst quickly. Mowing helps a great deal with weeds, especially annual weeds. But occasionally, a herbicide may be needed as it can take years of mowing to get control over a dense weed patch.

If you are spraying for perennial weeds, the best time to do this in the fall, and if mowing has not been adequate to control the annual weeds then it is best to spray for them in the spring. However, they can be basically managed with mowing. Prior to using a herbicide, it is important to know what is safe to use on grazing pastures. Herbicides are labelled for a site, therefore, ensure you are purchasing a pasture herbicide, not a lawn product. On the pasture herbicide label, there will be grazing guidelines. Following these grazing guidelines will ensure the safety of your horse.

5)      Fertilizer

As previously mentioned, grazing is hard on pasture plants. Supporting the plants with fertilizer can allow you to get a lot more out of your pasture. Prior to purchasing fertilizer, take a soil test and send it to the lab!! This will give you valuable information on the nutrients that you should be adding to that field.

What and When to Plant?

The two general types of pasture grasses are warm-season and cool season grasses. Your geographical area will determine which species will do best. In Ontario, cool-season grasses are what is planted along with a variety of legumes. The main difference between these grasses is the climate in which they do best, but there are also some general nutritional differences as well. Warm-season grasses are typically higher in crude fiber, and lower in crude protein, non-structural carbohydrates as well as energy. Cool-season grasses are lower in fiber, and higher in crude protein, non-structural carbohydrates and energy.

What to plant is unique to the herd and geographical location. However, a popular mix of species that research has shown does well under horse grazing is: perennial ryegrass, endophyte-free tall fescue, Kentucky bluegrass, timothy, and generally a legume such as white clover.

Rejuvenating a pasture can be challenging. In Ontario, the late summer is when you want to be planting your pasture mixes. You will then want to add fertilizer to promote ideal growth. If this is not an option, using a frost seeding technique in March can work well to contribute to pasture rejuvenation too.

What about Easy Keepers?

A question that I get asked frequently, is what species are best for easy keepers or insulin resistant horses. The unfortunate answer is that some horses simply cannot handle pasture grazing. There are better times of the day to graze, and keeping your pasture well-managed and not overgrazed can help…but occasionally, these horses do just need less rich forage.

That being said, there is some new research on teff, which has shown a lower insulin response when horses are grazing this grass. In the study, the horses were grazed on different forage species, and it was shown that the horses grazing teff had lower peak insulin responses when compared to the horses grazing cool season grasses. This is an interesting area of research, but teff can be a difficult forage to plant and harvest. Overall, more research is required before clear conclusions can be assumed.

I personally investigated some teff hay for my easy keeper mare this past summer. I tested both the grass mix hay I normally purchase as well as this other teff option. The teff hay ended up being higher in digestible energy, crude protein, and fat – however, it was lower in non-structural carbohydrates. Since neither forage was over the 12% NSC cut-off for metabolic horses, I decided against purchasing the teff hay.

To conclude, there are many different aspects to pasture management, but the most significant issue in Ontario tends to be over-grazing. Hopefully, this blog post has given you some useful management tactics that can help you get the most out of your pasture!! Since so much of this is unique to the location, number of horses, pasture size etc. I am always happy to discuss it in detail over a basic remote consultation if you are looking for a pasture plan that best suits your herd.

If you have any questions please email me at balancedbaynutrition@gmail.com 

References:

DeBoer, M. L., Hathaway, M. R., Kuhle, K. J., Weber, P. S. D., Reiter, A. S., Sheaffer, C. C., … & Martinson, K. L. (2018). Glucose and insulin response of horses grazing alfalfa, perennial cool-season grass, and teff across seasons. Journal of equine veterinary science, 68, 33-38.

Fleurance, G., Sallé, G., Lansade, L., Wimel, L., & Dumont, B. (2022). Comparing the effects of horse grazing alone or with cattle on horse parasitism and vegetation use in a mesophile pasture. Grass and Forage Science, 77(3), 175-188.

Kenny, L. B., Burk, A., & Williams, C. A. (2018). Managing equine grazing for pasture productivity. In Horse pasture management (pp. 141-155). Elsevier.

Longland, A. (2013). Pastures and pasture management. Equine Applied and Clinical Nutrition, Philadelphia, 332-350.

Staniar, W. B., Bussard, J. R., Repard, N. M., Hall, M. H., & Burk, A. O. (2010). Voluntary intake and digestibility of teff hay fed to horses. Journal of animal science, 88(10), 3296-3303.

Weinert, J. R., & Williams, C. A. (2018). Recovery of pasture forage production following winter rest in continuous and rotational horse grazing systems. Journal of Equine Veterinary Science, 70, 32-37.