The Four Principles of Soil Health Applied to Forages

Soil Health is one of the main tools that will help sustain farms in the future. It will help us feed the world. NRCS recognizes four principles of soil health. They are very basic but can be applied many different ways to any agricultural system. Here is how I implement them on my forage fields.

1. Plant Diversity

Diversity is the spice of life; except for very specific instances I avoid monocultures. When most people think of monocultures they think of annual crops, but it is very easy to get into a monoculture perennial forage system without realizing it. In our region of Tennessee, a lot of farmers’ pastures have turned into monocultures of fescue when it is cool and crabgrass when it is warm. This locks them into depending on these two species making a crop as well as reducing the biodiversity in the root system.

When I am planting perennial pasture I normally do a minimum three species planting mix depending on what my goals are. Some of my favorite grasses for my area are fescue, orchardgrass, bromegrass, and crabgrass. I normally mix some annuals such as triticale or rye in. For clovers I like red and white with a little crimson mixed in. I am a big fan of small amounts of vetch. I also like mixing a small amount of tillage radishes in. This biodiversity means something is always growing and there for my animals to eat. It also provides multiple root structures for the microbes in the soil.

For annual mixes I like to get up to a minimum 6 species or so mix. I like keeping a couple of the seeding rates high (normally cereal rye in the spring and sudex in the summer) and then just sprinkle in several other species. This seems to work best on my farm under my management strategy. Keep in mind the different growing habits of different species and how they must be managed when building a mix to plant.

There are lots of resources out there to help you come up with seeding mixes. The best place to start is your local soil conservation district or ag extension agent.

Don’t be scared to mix annuals with perennials, but pay attention to what you are doing. Some annuals can smother out existing perennial pasture. Some perennials will overwhelm annual seedlings and you won’t get a stand. When used in sync it will give you the best of both worlds.

2. Minimize Disturbance

Most people have a vision in their head of the original Flat Bottom Steel Plow designed by Mr. John Deere as being the only source of soil disturbance. They think that as long as they are not tilling below about three inches they have not disturbed the soil. This is about as far from the truth as you can get. Soil Disturbances come in many ways and have many different effects. Not all disturbances are bad, if you have a reason for what you are doing and a plan to manage the effects. Some of the common ones I see are:

Cutting Hay

This is probably the biggest soil disturbance you can do on the average cattle farm. You take a massive stand of mature plants and remove them down to less than two inches. This exposes and allows sunlight to penetrate to the soil which then bakes the life out of the top two inches. Because you took away the energy source for the plants 75 percent of the roots immediately die, and it will be over two weeks before new root growth happens. You have also allowed any seeds that are laying on top of the ground the opportunity to germinate and grow. In my experience about 114 percent of those seeds will be an undesirable weed. This is just the beginning of what hay does to plants and the soil.

Overgrazing

Many farms I see are either overgrazing or practicing rotational overgrazing. Rotational overgrazing has similar effects to cutting hay. Continued overgrazing allows for erosion, very little plant production, very little root production, no soil shading, and the list goes on.

Fertilizing- Fertilizer can be just as bad as it is good. When used in large individual quantities it can “shock” or “burn” the life out of the soil. Most farmers only notice the extreme effects such as plant loss, but there are always effects.

These are just a few examples. The biggest thing is think about what you are doing, what it is doing to the soil, and how you are going to manage the results.

3. Keep Plants Growing

This is easier in a forage based system compare to cropland. Basically, just make sure you always have something growing. Reduce overgrazing to allow increased plant vigor. Lock your animals to a sacrifice area during winter or select times to maintain grass heights on the rest of the farm of three inches or more. Incorporate more variety of growing seasons in your forages or plant annuals to fill growth gaps. Also, keep recovery time in mind. A four-inch plant can recover and resume growing up to two weeks sooner than a two inch plant.

4. Keep the Soil Covered

Maintain a good stand of grass that is over three inches high. This keeps the soil shaded and acts to cool the soil in the summer and keep it warmer in the winter. This provides multiple benefits to both plants and soil life. Typical bare spots in pastures include overgrazed spots of desirable species, hay ring spots, lots, cattle trails, around watering troughs, etc. Also remember, a bare spot is a future weed patch.

Follow these basic principles to start building soil health on your farm. Results will not be instantaneous but well worth it in the long run. Most of us will measure the time spent on our farms by decades, so don’t sacrifice the future for the present.