Uniform grazing distribution difficult with converging soil types
Posted on: Oct 12, 2012
Grazing managers often discuss the importance of uniform grazing distribution, which means having livestock graze plants evenly across the pasture. Lacking good distribution, livestock will often graze some plants heavily, while other plants in the same pasture may be grazed minimally. Poor distribution and the associated uneven utilization rates affects plant recovery times between grazings, nutrient content of the forage, and even wildlife habitat. Achieving more uniform utilization rates with good distribution often times makes grazing management easier (depending on your objectives).
On one Montana ranch, achieving uniform utilization rates proved to be quite difficult due to multiple converging soil types in the same pasture. Different soil types often possess different plant species, and cattle may graze them differently. The photos below show such an example.
Different utilization rates are readily apparent in these photos. Where cattle grazed lightly, abundant standing forage is visible. Conversely, use rates appear higher with little standing forage just feet away. (In the photo to the left, three soil types appear to converge, and cattle grazed all three differently.)
Grazing managers have little means of correcting this situation. In the photos above, this pasture was grazed for only 7 days, and stock densities reached 2 head per acre. Use of more intensive fencing and/or herding are options, but the return per effort invested makes such tools undesirable. Maintaining the health and performance of this pasture thus depends more on ensuring grazing durations are kept short (7 days is as long as cattle should be in this pasture), recovery periods between grazings are lengthy, and timing of grazings should be altered each year so that plants are not grazed at the same time each year. With such tactics, land health and wildlife habitat may both be maintained.