A Good Grazing Manager’s Lingo
Posted on: Sep 01, 2014
How do good grazing managers describe their management practices? Ranch Advisory recently traveled to central Montana and found an example. Here's how one young grazing manager described management of a pasture:
"We harvested 9 ADAs (animal days per acre) in late May, then offered an 80-day rest period, and pulled another 17 ADAs in late August. Next year, we won't do two grazes of this pasture due to plant vigor concerns, but will offer spring rest and graze again in the fall. We should also extend the 80-day rest period to 90 or even 100 days."
Translation: The ranch set a stocking rate of 9 animal days per acre for the spring graze, which is calculated by multiplying the herd size by the grazing duration in the pasture and dividing by the acres in the pasture. ("X" number of cows, multipled by "Y" number of days in the pasture, divided by "Z" acres equals the stocking rate.) The stocking rate, as expressed in ADAs by this cowboy, is the grazing manager's primary expression of pasture performance. Stocking rate reveals a great deal about rangeland health and the ability of the operation to generate revenue. The 9 ADAs was combined with the 17 ADAs harvested in late August for a total of 26 ADAs harvested in that pasture. The number 26 serves as a reference point to be compared to prior years (ideally, if management practices improve rangeland helath, stocking rate may increase through time) and also as a planning tool for future years. Next, the ranch planned an 80-day recovery period between grazing events in which grasses were offerend an uninterrupted opportunity for growth. They could then replenish lost leaf, root, and energy reserves before the next grazing event. This manager then used the early-warning indicator of reduced plant vigor to guide him in lengthening this recovery period to 90 or 100 days in years in which the pasture is grazed twice. This should help correct the plant vigor issue he observed when examining the pasture in fall 2014. Because that recovery period wasn't long enough, the pasture will not be grazed in spring 2015, but will be allowed uninterrupted growth until fall. In coming years, that 90 or 100 day recovery period can be evaluated to determine if plant vigor concerns have diminished.
Much debate has centered in the past on use of grazing on western rangelands, but little focus is placed on grazing management. Too often, opponents of grazing attack the tool of grazing, just as proponents support the tool of grazing. Both sides miss the critical point that, as a tool, grazing may be well managed or poorly managed. Like a hammer that may either hit you on the head and cause pain, or build you a house and create comfort, grazing has various forms in which it may be used. The use of that tool through time (and the associated recovery periods and animal impact that accompany it) determines such important factors as rangeland health, riparian condition, wildlife habitat, and financial wellbeing of the operation.
As this Montana grazing manager spoke, he was surrounded by healthy rangelands and varied wildlife such as elk, mule deer, sandhill cranes, and kestrels. The land he manages appeared to be thriving. Yet his vocabulary shows his desire to further improve the performance of the pasture where he stood. It is in this context of management actions where the grazing debates in our nation need to go.