Improving Soil Health with Grazing

Grazing is practiced by many Pennsylvania farmers. It is an excellent type of land use on soils that are steep, shallow, rocky, poorly drained, as well as on deep, level soils. The perennial vegetation permanently protects the soil from erosion, there is no soil tillage, you have living roots in the soil year-round, and the perennial grasses and forbs help build soil health. Further, grazing can be a very interesting type of farming for producers with limited acres who perhaps don't farm full-time. Infrastructure investments in buildings and equipment are relatively small and it is possible to start small and continue building up your herd and expertise as you go. This is difficult with other types of agriculture such as dairy farming or field crop production. But you can also graze in a way that degrades soil. In fact, grazing has a bad name in many parts of the world due to the common practice of overgrazing. So, as we enter into the winter, what are some principles that graziers should abide by to help their soils improve?

1. Leave at least 4 inches of residual. You may be thinking this is just a waste of resources because these leaves often turn brown and decompose on the soil surface come spring. However, the standing residual helps improve the microclimate at the soil surface, protecting buds developed in the fall for new growth in the spring. The standing vegetation will also capture more snow than if you graze to the ground, further protecting these buds. If you graze to the soil surface, any new growth will have to first use reserves in the roots, and that weakens the plant. One result will be faster regrowth in the spring. But soil health also improves because a more vigorous root system helps improve the soil, while any decomposing dead leaves will feed soil life. Besides, the residual also protects the soil from erosion.
2. Move animals regularly and limit access to previously grazed pastures until they are ready for regrazing. Today we have ready access to mobile fencing that can be used to offer grazing animals only as much as they can eat in a short time period. For example, if you move animals daily, and then don’t come back to the same paddock until it is ready to be grazed again, you protect that soil tremendously from being compacted by animals that go back and forth over it to consume regrowth. Moving animals regularly becomes especially important when the soil is sloppy. Regular animal movement also assists in distributing nutrients from manure and urine more uniformly. A mobile watering system can be of great help to make regular animal movement easy. However, even if you have to allow animals access to a permanent water source you can creatively work with your (mobile) fencing to create lanes so the animals can access water while keeping them out of the grazed pasture.
3. Have a hard surface or sacrifice area for emergencies. When the soil stays very wet, it may be better to keep them on this reserved area where they are fed hay instead of letting them muck up all your pastures.
4. Have a diversity of pastures and mixtures. If you have a diversity of pastures, you can better extend the grazing season, and thus keep rotating your animals around the farm. Diversity in the pasture itself is also beneficial – for example, by mixing legumes and grasses, you can improve the nitrogen status of the forage, and you can eliminate or greatly reduce the amount of nitrogen you have to add. The different root types of grasses and legumes occupy different niches in the soil and help create porosity and soil aggregation throughout the profile.
5. Take soil tests and follow recommendations. Perhaps you have never tested your soil. This is not uncommon among graziers. But if your soil pH is low, for example, your forages will not be very productive, and the root systems will be small, leading to poor soil health. You may also have a critical deficiency of a certain nutrient that you should add. Penn State's Agricultural Analytical Lab offers excellent soil testing services and quick turnaround with recommendations calibrated for our soils and climate.