Maximize Grazing and Improving Soil Health

"When my soil is healthy, my animals are healthy" – was the adage one of the graziers I’ve worked with.  As a person interested in improving soil health, this really piqued my interest. So how do you improve soil health while maximizing pasture production? Let us boil it down to a few key points:

• Don't graze your pastures to the ground. A common rule of thumb is 'graze half – leave half'. The key for perennial cool season pastures is to leave at least 3-4 inches of vegetation when the animals are rotated out of the pasture. For warm-season grasses, more residual needs to be left – at least 6-8 inches. This is because grasses store reserves for regrowth in the stem just above the soil surface. When you leave sufficient residual, they can quickly recover from the shock of losing so much leaf matter. If you remove these reserves, they have to pull energy from the roots and that severely impacts the root system – which reduces soil health! Further, any trampled material will decompose and contribute to soil organic matter, feeding the soil life.
• Allow for sufficient regrowth time before letting the animals back in. This is the principle behind rotational grazing – you graze for a short period (typically no longer than 3 days) and then let the pasture rest for a long period (typically 20-30 days, depending on weather) before grazing them again. This helps the root system to develop as well as the top-growth. Additionally, the reduced exposure of the soil to the animal impact reduces the potential for detrimental soil compaction. If the animals are left in the field for longer than 3 days they typically go back and graze the new regrowth and this really weakens the root system.
• Maximize the grazing season by diversifying your grazing supply. Grazing farmers in the Northeastern U.S. rely first and foremost on cool-season grasses for grazing. These grasses have two big flushes of production: the biggest in the spring, after which they typically go into a summer slump when the weather is hot and dry, and then in the fall they resume growth and produce another bump in production. Warm-season perennial grasses such as switchgrass, big and little bluestem, and Indiangrass have a different growth pattern. These grasses produce most in the heat of summer. They are the mainstay on prairies that used to feed our herbivores but have gone out of fashion for commercial grazing in the Northeast. They got a bad rep due to poor forage quality testing, but this needs to be revised based on ground-breaking work by Dr. Pat Keiser from University of Tennessee and others, who recorded excellent Average Daily Gains (as much as 2.5 lb./day) of grazing weaned steers. Warm-season perennials can be an excellent place to graze in summer, which allows the cool season pastures rest. Another interesting thing about them is their tremendous root system that helps to improve soil organic matter content and aggregation - considered to be the reason that the best soils in the world developed under prairie. It is also possible to use warm-season annual mixes for summer grazing. Sometimes, these are reserved until fall so that the cool season pastures can be rested for stockpiling. Cool season annuals can be planted after the warm-season annuals – options are oats/peas for late fall grazing, or rye or wheat for winter and/or early spring grazing.
• Use no-tillage to establish your annuals and perennials. No-tillage helps preserve the soil structure and organic matter in your soils. It has proven to make your soil resist soil compaction. Pugging is a lot less on a no-till soil than a tilled soil. Further, no-till helps favor soil life – you will have more earthworms, soil insects and microbes which improve soil health.
• Monitor soil moisture conditions and cattle impact on the soil. When you notice the animals starting to tear up the pasture and soil, it is important to move them more quickly, or - if things get really dicey – to put them in a sacrifice lot or in the barn.

These are five keys to help you maximize grazing while at the same time improving your soil!