It seems that HM is considerably more labor intensive than other schemes. I'd be worried the extra cost would eat up the promised gains. How would you address such fears?
It can be more labor intensive, absolutely. Anybody thinking they can get into ranching (or any agriculture for that matter) and do it right, and not work their butt off is very naive. Labor costs most certainly are a factor in any management plan. HMPG is no exception.
So you keep saying but that doesn't answer the question. Reportedly, the range was being over-grazed. Even if the amount of forage is increased, why would it be necessarily enough for more than 150 heads of cattle?
I think your stumbling block is this: Overgrazing doesn't increase the forage the animals eat. It actually reduces it. If it is being over-grazed then the flora is being stressed and not growing, thus not producing as much forage, thus supporting fewer cattle. So if highly stressed over-grazed land can support say 300 cattle, then that same land grazed properly can support at least 400-500, maybe more. Even 1 cow can over-graze where 100 wouldn't. It is a factor of time and timing not numbers of cattle. Think of it this way. plant a seed. In a week or so it sprouts with a single leaf. Graze it then and it produces what? A microscopic tiny amount of forage? And then because it is grazed so young it dies, never to regenerate? But maybe that seed if allowed to grow a few months might produce 5 pounds of forage. Graze it then and you could take 2-3 pounds of that growth without harming the plant, as long as after grazing the plant is allowed to recover, and the grazing left behind manure and urine to fertilize the new growth. So it is all about times and timing, not numbers of cattle. But numbers do affect some things. More numbers of cattle leave more manure. So if you time it right and are able to get more cattle, then more manure, and more vigorous regrowth. Time it wrong and you kill the plants and dead plants don't feed anything, cows nor wildlife. No forage means no animals, means no manure, means slow recovery. So you can take your feedback curve in a positive direction and increasing grazing, or you can take your feedback curve in a negative direction with reduced grazing. Whenever you see a "solution" to over-grazing being reducing the numbers of cattle, then you know they are on that negative feedback curve and don't understand how to generate the positive feedback curve.
How was established that compacting the soil will be beneficial? Intuitively it would seem like compacted soil would make burrowing more difficult. Presumably you know of experiments showing that this is not true?
"Compaction" is too general a term here. Deep compaction is not good. But compression around the seeds can help dormant seeds to sprout (when water and nitrogen is present too). Animal impact can break the crust, compress the seed sprouting zone, and still not compress the deep zone all simultaneously. But it needs to be timed right and the cattle need removed after. What I was referring to in the first comment was the beneficial effects of soil structure seen in the rhizosphere.
With what you say about plant cover, it sounds like you say that the landscape will become more grassland-like. Now, given that the tortoises do not spread into grassland, it seems odd that this would be beneficial.
I wasn't talking about the sod producing grasslands found in areas with more moisture. I was talking about non-sod forming desert bunch grasses and forbs. Tortoise do great in that type of ecosystem. It is nearly ideal.
Most importantly, since research suggest that livestock has a direct negative impact on the tortoises, how can we be sure that effects you claim will overcompensate for that?
Actually the research is inconclusive, if the truth be told. But I'll admit that in some cases grazing can be detrimental. Other cases a positive affect. So that's where proactive monitoring is critical, a major part of every holistic managed grazing plan. Without the monitoring and adaptive parts, it will likely fail sooner or later.
Basically using cattle instead of herbicide. Makes a lot of sense.
It seems, though, like this would require very close monitoring of the cattle. Is that even economically feasible?
Herbicide isn't free either. Cattle can be sold at a profit. The line between profit and loss is narrow though. That obviously needs carefully considered when making the plan. It can be done and it has been done, but not always easy. It might take some creative thinking and human ingenuity to pull it off. There are actually business models where animals are rented to both public and private concerns to provide biological invasives control. That might be one way to approach it. It also might be possible to generate enough profit just from the sale of beef. Maybe some combination of the above. And yes, VERY close monitoring is required.
My understanding was that the restrictions would be imposed dynamically, each year based upon the range condition. To me, it sounded very much like what you proposed. Except of course, that it would be a yearly thing rather than the continuous real-time monitoring you propose.
Yes, that's correct. And of course the restrictions were arbitrary and ill advised, unless made in some context of exactly what type of grazing would be done. The restrictions are very likely spot on perfect in the context of continuous grazing, but wouldn't even be realistic in HMPG.