Pasture Management for Bison

Cathie Erichsen Arychuk, P.Ag.
Bison Production Specialist
AAFRD, Fairview

Summary

Good pasture management looks after both the bison and the plants. Proper management of pasture plants will enhance forage production and quality, and will extend the life of your pasture. If you look after the grass, it will look after the bison.

Some bison producers see their pastures simply as a place to keep bison. This makes sense, doesn't it? After all, you raise bison. Management on many farms emphasizes the animals, not the land. Often, this results in pastures that rapidly become weedy, unproductive and sod_bound. Many of these pastures need to be broken and reseeded every five or six years. Changing your management focus may help make you a better pasture manager, and save you some money.

Most forage plants used in pastures are long_lived perennials. To make to best use of these plants, your pasture management should balance bison needs with plants needs. We know bison need access to plenty of good quality forage for grazing. But what do the plants need?

One key to keeping forage plants productive is to find a balance between grazing and rest. This is the basic principle in controlled grazing. Controlled grazing is not new. Wild bison herds practiced it, both instinctively and by necessity. The animals bunched together in herds to avoid predation and were always on the move to fresh pasture.

Forage plants are stressed by overgrazing. Overgrazing is now commonly defines as grazing a plant before it has recovered from the previous grazing. Overgrazing occurs when:

1. Animals remain in a pasture long enough to regraze plants that are recovering. During periods of rapid plant growth, this can happen in just a few days.
2. Bringing animals back to a paddock too quickly.

Inadequate rest after grazing weakens forage plants. When a plant is bitten off during an active growth period, photosynthesis stops. The plant has to use energy reserves from the crown and stem bases to grow new leaf material so that photosynthesis can resume. These reserves then have to be replaced so the plant can survive the winter. Overgrazing weakens the plant, and if it happens repeatedly, can eventually kill it. Other less productive but more grazing tolerant plants move in to replace these desirable plants. Often these are weeds.

Managed grazing moves bison between several different pastures (at least two) to allow forage plants to recover after they have been grazed and before they are grazed again. Management attempts to provide the plants with the recovery time they need while maintaining productive, high quality pastures for the bison. Good pasture managers look after their grass, and let the grass look after the bison.