Central Kentucky Agricultural Extension agents and University of Kentucky Ag Equine Programs hosted the 11th annual Pastures Please!! pasture management workshop virtually on Jan. 26. The workshop included three expert talks about managing carbohydrates in the equine diet, current herbicide effectiveness on weed control and investments for pasture management.

Ray Smith, PhD, professor and forage extension specialist and Krista Lea, MS, plant and soil research analyst and coordinator of the UK Horse Pasture, both from UK’s Department of Plant and Soil Sciences, concluded the program with a presentation about wise investments for pasture management.

The discussion highlighted the steps to take in order to evaluate pastures and get the best use out of them. Smith detailed how management practices such as weed control, use of fertilizers, nitrogen, overseeding and pasture resting can improve a pasture.

Smith began with weed control. He shared an image of a pasture full of flowering buttercup and pointed out that by the time weeds get to that point, it is too late to use herbicides or to manage them effectively.

“Weed control is often misused. You want to make sure you know what weeds are there, and spray for the ones that are there. Some herbicides have good residual control, meaning they control weeds even after spraying. Others don’t last very long. But the unintended consequence of killing weeds is you have bare soil, and then you need to do something to cover that bare soil… So, you’ve got to be very careful with what herbicide you use because they have different wait periods before reseeding.” Smith said.

An average range for the cost of herbicides is $12-$25 per acre. Smith indicated that if weeds are rampant in a pasture, this is a small price to pay to help lessen the burden. When weeds are minimal, then the best recommendation is patience and good grazing management  

While weed control and management is a useful tactic, it is not the answer to all pasture problems. Other issues, such as low nutrient density, should be managed in other ways.

One of the ways that Smith encouraged nutrient management is through the use of fertilizer.

“Fertilizer is often misunderstood, in how to apply the fertilizer and when you need to apply the fertilizer. When I’m talking about fertilizer in this context, I’m going to talk about particularly in Kentucky, applying lime to change the pH, applying phosphorus and applying potassium. So, the real value of applying those nutrients is maximizing the production and also the stand life. It is safe to apply fertilizers and these particular products when the horses are on the field.” Smith said.

Using the fertilizers Smith mentioned can cost up to $65 per acre.

For the best results, Smith recommended a soil test be conducted to indicate what is needed so as to not overdo the concentration of a particular nutrient. Pastures should be soil tested every two to three years in order to accurately treat the pasture. Fertilizers may be applied any time of the year, except when the land is wet.

“You can’t fertilize your way out of poor management,” Smith said, meaning overgrazing and poor upkeep of pastures cannot be fixed with fertilizer.

Nitrogen, while it is a fertilizer, is its own entity for the purpose of pasture management. The use of it increases yield. Fall application of nitrogen is recommended and encourages leafy growth, strong roots and early spring growth. Early spring application boosts newly planting seedlings and helps develop overgrazed pastures, but can result in excess pasture growth and more mowing. Remember that nitrogen is beneficial to all plant species, including weeds, so be judicious in the amount of nitrogen applied. The average cost of nitrogen is $23 per acre.

Smith addressed overseeding as an effective pasture management tool, but one that is often poorly executed. Overseeding allows for growth to occur in bare areas which, in turn, prevents weed growth. Timing and resting the growth is critical to development of the plants. In Kentucky, the ideal time for overseeding is in September.

The ideal planting depth when overseeding is between ¼ and ½ inches below the soil. Bluegrass does best when planted in the fall but takes a while to gain a decent amount of growth. Orchardgrass is the most shade tolerant grass, and therefore can compete well with existing grasses in a pasture. Perennial and annual ryegrass come up quickly, but since they are short-lived, they should only be used as a temporary fix for muddy or overgrazed areas in a pasture.

Smith closed out the session with information about resting pastures.

“Resting allows grasses to rebuild leaves and roots after grazing, increases stand life, increases forage quality, favors grasses over weeds, reduces soil erosion and nutrient leaching and the pasture looks better. And the cost of rest is free.” Smith said.

Pastures need to be rested in order to allow existing grasses to regrow leaves and restore carbohydrate reserves in long-term survival, according to Smith. Seedlings in particular are vulnerable to close grazing consistent hoof traffic. Allowing pasture an opportunity to rest also encourages improved forage production, which permits the feeding of less hay and grain.

Smith used images of experiments to further convey his point. The comparisons between rested pasture and continuously grazed pasture growth show that resting is beneficial for plant growth.

To properly rest a pasture, it should be grazed down to 3-4 inches, and then mowed if the pasture is uneven. Horses should be relocated off of the pasture for two to four weeks in order to regrow about 8-10 inches of forage. After this, the horses may be returned to grazing in the pasture. Rotational grazing is a great method to allow pasture resting time.

For all of the pasture management practices that Smith discussed, the total cost would be about $153 per acre, done every three years. By doing this, the amount of usable forage in a pasture may be doubled.  

Smith shared resources for additional information, including the forage extension webpage, The Equine Science Review, county extension agents and the UK Horse Pasture Evaluation Program. A recording of the talk can be found on the KY Forages YouTube channel at Wise Investments for Pasture Management, Dr. Ray Smith.

Sydney Carter, a junior majoring in equine science and management and minoring in journalism, is a communications and student relations intern with UK Ag Equine Programs.