Category:Terrestrial Plants and Soils
Chris and commenters I want to emomcnd all on the thoughtful discussion.You can skip the narrative and dive into the points below:I have 30 years of experience as an NRCS range specialist and grazing specialist. I was raised on a small place near Abilene Texas so I've been around grazing pretty much all my life. I became aware of Short Duration Grazing advocated by Allen Savory in the early 1980s and worked with some of those systems in rangelands throughout Texas. They are complicated, sensitive and required consistent and continuous high levels of management. Some worked and some did not. I also saw high intensity-low frequency, and many other grazing systems at work along with fire and the other tools of range management.I became aware of Greg Judy's efforts with MOB grazing after being transferred to Iowa and now work with almost 10 of these systems from dairy to cow/calf. The difference between rangeland/prairies and pastures is day to night and I would not approach range management like pasture management. In pastures we can start over in our rangelands on my home ranch we can never start over.Point #1 Impacts on Soil Organic Matter cattle recycle about 85% of what they eat and deposit bacteria filled organic matter on the soil surface for worms and beetles to bury. I am also convinced, no data, that the pulses of root die back and regrowth from mob grazing events can beat preservation prairies in carbon storage where that cycle occurs about once per year instead of two to four times. That is why i believe soil O.M. impact is fast.Point #2 Impact on weeds:Like Kathy I've helped ranchers teach cattle to eat canada, musk and other thistles etc. I agree that the perennials may survive long term but their impact is lessened immediately. In the mob systems I work with two awesome things are occurring. Musk thistle which is a biennial decreased more than 80% by the second year. In oak savannahs we are seeing up to 1000 oak, walnut, and hickory seedlings per acre after mob grazing with plenty surviving into year 2 and 3. My observation is that the forage that grows after a grazing event with 90+ days rest can outcompete most annual weeds. The tree seedlings are savannah species that are used to waiting out herbaceous vegetation, fire and even some grazing then bolting past the forage to dominate their space. I work with pasture so it's more of a turf versus bunch scenario, weed seeds have a hard time finding bare ground. Acorns from our 150 year old oaks can be pushed into the soft soil by hooves and some grow!Point #3 What is MOB GrazingIn the Midwest for pasture 250,000 pounds of liveweight per acre or more, grazing for a day or less, with not less than 45 days rest up to 120 days rest. This will be different for range and for drier and for changes in weather and on and on. The art is in high stock density, long rest and being careful to not abuse livestock in the last trimester or early lactation.Point #4 When does it work?Mob grazing is a tool and nothing more as a grazing management system. It works when the landowner is putting in the effort and has the intelligence to make it work. I'm working with the TNC now to use MOB grazing on reed canary grass dominated floodplain that should be sedge meadow. Other methods can work but are erased by each flood event. We are trying grazing, 2011 is first year, to check impact in a 99% dominated reed canary area where there is no hope otherwise to get some sedges back into the mix.Point #5 Forage HealthAs Rick Warren might say it's not about the grass We are seeing natives, legumes, and many desirable species show up after the first grazing event. Even though there is little research the proof is still in the pudding. The oldest MOB system that i work with has doubled cow/calf numbers in 3 years with no seed, no fertilizer, no forage degraded, fewer weeds, and they sell grass-finished beef at 6 chain groceries competing with grain fed.You are close enough for show and tell next growing season. Let's continue to chat.
Pages in category "Terrestrial Plants and Soils"
The following 5 pages are in this category, out of 5 total.