Is Mob Grazing as effective as people say?

https://onpasture.com/2017/11/06/is-mob-grazing-as-effective-as-we-thought/

Read this article the other day and thought I'd put it up for discussion.  I've never grazed any animals, so I am certainly not an expert or knowledge source.  It has been my experience in other things that people do tend to exaggerate or over emphasize the benefits of things online, and was wondering if Mob grazing is one of those cases.  What really striked me in this article is that mob grazing was found to have less consumed forage and less soil creation, which I would have thought otherwise.  

Thoughts?

Carson,

I don't have access to the article they are referencing in Michigan, but I am very excited that this is being discussed and tested. The only thing they didn't reference is invasion of pastures by noxious weeds and saplings, which presumably is improved by mob grazing. There were no assays of soil microbes reported which is the ultimate goal of any ruminant system in my world. The density of their rotational grazing is pretty high, and that may be a factor. I have been suspicious that there is a limit to stocking density, the old pictures don't show bison so close they are touching after all.

The most interesting to me is the organic matter is increasing at 1/3 of a % per year. That is awesome, I mean I would love more but that is kicking! The old saying was you couldn't increase topsoil or OM more than 1/16" or 1/10% per year. This is really great. The other advantage to mob grazing in my understanding is that the organics go much deeper, promoting deeper rooting due to an acceptable biome further in the B strata. This doesn't seem borne out by this study, and maybe keylining/subsoiling is the answer there, as MArk Shepard is doing.

I also haven’t grazed any animals, yet. It is one of my goals to have cows on my farm in managed rotational grazing, but this is about three years away.

Here’s my take on the article. I think there’s a few empty spaces, like when they talk about cow weight gain under rotational or mob grazing, they do differentiate between cool season grasses, warm season, annual and perennial, but without naming specific varieties and there’s no mention of specific legumes or other forbs. Grazing endophyte fescues for example, results in poor cow weight gain, but this can be offset by the cows grazing clovers in conjunction. There’s no mention of the water the cows drink. Maybe the cows in these studies stand in the ponds and pee & poop in the water they drink, which is what the farmers around me let happen, which can result in high parasite load and also have an affect on weight gain. I think this article lacks important details, which may be evident in the original research that this article is a summary of, as noted by the author at the beginning.

The article talks about impacts on the soil, and the author admits very limited research is available on soil organic matter changes under these grazing practices, but there is no mention if the pastures in these tests have dung beetles. Dung beetles can rapidly transport dung below ground increasing soil organic matter more quickly compared to pastures that don’t have dung beetles.

I think this particular article starts off presenting a question of doubt, right with the title and how it’s phrased - “Is mob grazing as effective as we thought?” I don’t know why they’re presenting doubt. I think summary articles of more in-depth works can sometimes be tailored to offer a certain view by choosing what information is used and omitted and how it’s presented.

James Freyr wrote:there is no mention if the pastures in these tests have dung beetles.

Save the dung beetle!  https://www.reuters.com/article/us-environment-economy/save-the-dung-beetle-global-science-chief-says-biodiversity-vital-idUSKBN1CO2CI

First of all, thanks Carson for posting this link and opening the discussion.  I think TJ, James and Tyler have raised excellent points.  In the spirit of openness and honesty, I've never rotationally grazed cattle or any other animal, despite trying very hard to convince dairy farmers I've worked for to let me try it.  I've been reading and watching quite a bit about the topic for many years and I hope to be able to put that knowledge into actual practice this year on my own bit of land.

I agree with James that the author seems to have a bias going in to the article, though I should admit that I have a bias in the other direction based on my reading and information gathering.  I purposely do not call that research as I define research as actual experimentation and data collection, not reading what others have researched.  I also think that the scientific method is flawed, at least as taught to me throughout grade and high school as I have always felt that stating a hypothesis before starting an experiment establishes a bias right from the start.  One study or experiment can also have flawed results, either due to faulty design, pure chance, or both.  The best way to make a determination is to do a meta-analysis of many studies and also to consider the statistical significance of the results, not just depend on a single study or small sample of studies.  There are very few studies in this area, so that doesn't seem to be an option.  I should also state that I'm no expert on statistics or proper experimentation design, though it's been a subject of interest to me and I've done one or two undergrad courses and a grad course on stats, so I probably only know enough to be dangerous.  With that said, I'll tell you what I think of this article and the study it's based on.

Almost right away, this gets my spidey sense tingling:  

an RG system refers to stocking densities less than 100,000 pounds of bodyweight per acre and one- to 20-day stays in a paddock before rotating to the next one.

 Seriously?  Anywhere from 1 to 20 days?  After 3 days on the same paddock, the cattle will be grazing the tender shoots of the species they first grazed.  At 20 days on the same paddock is there any meaningful difference between that kind of rotation and just constant stocking?  If you want a meaningful experiment, you would need to break the 1-20 days into subsets of 1, 3, 5, 10 and 20 days, or something like that and compare each of those to the MOB grazing.  

Then we run into math.  Here's the breakdown of the notation he's using:

For example, a cattleman may have 200 heifers that each weigh 1,000 pounds on a 1-acre tall fescue-based paddock for eight hours (0.33 days), and those animals may not rotate back to this area for 60 days.

To present the subject, a shorthand notation that Dr. Woody Lane and I have developed (see Dr. Lane’s article in the June issue of Progressive Forage) will be used. For instance, the example of mob-grazed heifers mentioned above could be summarized with the shorthand MOB,0.33,200K (note the lack of spaces).

Similarly, a rotational grazing (RG) system where those same 200 heifers grazed a 10-acre, tall fescue-based paddock for three days before being rotated to the next 10-acre paddock could be described with the shorthand of RG,3,20K.

So, under the MOB notation, it's 200 heifers on 1 acre paddocks, 3 times a day, for a total of 3 acres per day.  The RG notation is the same number of heifers on 10 acres for 3 days, so 200 heifers on 10/3= 3.3 acres a day, 10% more acreage per day.  That's not an equal comparison.

Now we get

In Michigan, perennial cool-season grass pastures had forage up to 30 percent lower in protein and 15 percent lower in digestibility when managed under a MOB,0.33,100K system compared to an RG,1,30K system.

which means 100 heifers on 1 acre, 3 times a day for 3 acres a day compared to 100 heifers on 3.3 acres for a day (100/3.3=30) so, again, 10% more pasture.  That means that the MOB is eating more of the grasses as they have less available and, as the top part of the plant has more energy and protein available, they're probably eating roughly 20% more of the plant with the diminishing returns, stressing the plant that much more, resulting in poorer regrowth on the MOB pasture.  The lower down on the plant they eat, the lower the protein content and the lower the digestibility, so we're just seeing what we'd expect to see. Wait, it gets better.

Arkansas, an RG,1,50K system – meant to represent a MOB-like system common in their region – resulted in a significant loss of body condition in cows compared to an RG,6,5K system.

 Under the previous nomenclature, the RG,1,50k could be 50 heifers on 1 acre for a day, or 50 heifers on 6 acres in 6 days and RG,6,5K would be 50 heifers on 10 acres for 6 days, or 1.67 acres per day.  With 60% fewer acres a day for the same number of heifers, is it a surprise that there would be a loss in BC for the RG,1,50k group?  

Let's get stupid:

In contrast, researchers in Nebraska found that yearling steer gains averaged 0.4 pounds per head per day on a MOB,0.5,200K while an RG,10,5K system produced 1.5 pounds per head per day (Figure 1).

 So, 200 heifers on 1 acre twice a day, so 2 acres a day compared to 200 heifers on 40 acres (200/5=40) for 10 days.  200 heifers on 20 acres in 10 days vs 200 heifers on 40 acres for 10 days; twice the acreage for the latter group should produce better gains per head.  With twice as much pasture available I don't think a 300% increase in gains per head is surprising.

Here's where he's being completely disingenuous:

They found that cattle grazing in a MOB,0.5,200K system took 5,551 steps per day, while cattle in an RG,15,7.5K took an average of 1,592 fewer steps each day. Their observation was that this was likely the result of having long (300 feet) and narrow (12 feet) rectangular paddocks where animals were stocked so densely they had to regularly move around other cattle to find enough forage.

 Those numbers really jump out at you, right?  5,551 steps per day versus only 1,592 steps per da... wait a minute, that's 1,592 FEWER steps per day, so actually 3959 steps per day, but that doesn't jump off the page like printing 5,551 and 1,592.  If Mr. Dennis Hancock hadn't already lost your respect for  fucking with the numbers, he should right here.  The reason the MOB group has more steps also isn't due to having

to regularly move around other cattle to find enough forage

it's because the paddock set-up will have travel lanes back to the water supply that fence the heifers out of the recently grazed paddocks so they don't re-graze the new shoots, thereby weakening the grazed plants.  If you watch any video of MOB grazing, they're not jockeying for position, they're just standing and eating.  If they're grazing a large paddock for 15 days, they're wandering all around to find the new shoots on the best plants.  At this point I'm pretty pissed at this Hancock guy.

Species shift:

Each of the researchers stated the variability in species diversity they observed seemed to have more to do with weather events than grazing management

is the over-riding conclusion, but it's not mentioned until after the Cock says

they tended to lose shorter-growing grass and legume species in the MOB,0.33,100K relative to the RG,1,30K systems

and no grazer wants to lose legume species.  This guy's not biased, is he?

The efficiency of forage use is often the most hotly debated aspect between advocates for rotational and mob grazing. In Nebraska, the MOB,0.5,200K resulted in 56 percent of the forage being trampled while 33 percent disappeared (likely consumed; Figure 2). In contrast, the RG,10,5K system resulted in only 19 percent being trampled and 44 percent being consumed.

 Again, we're comparing 200 heifers on 20 acres for 10 days vs. 200 heifers on 40 acres for 10 days.  Of course you're going to get more trampling with twice the stocking rate.  Add to that, the top 33% of the plant has the majority of the energy in the grasses, so consuming 33%, trampling 56% and leaving 11% standing is pretty much the picture of perfect MOB grazing management.    

Additional research in Nebraska examined incremental increases in MOB stocking densities of up to 750,000 pounds of bodyweight per acre and found the rate of trampling did not increase at stocking densities greater than 100,000 pounds of bodyweight per acre.

 How's that for a non sequitur?  It has nothing to do with anything, but it implies that increasing stocking density doesn't result in any benefit.  

Proponents of mob grazing have observed that the trampling of forage keeps the soil from heating up in the sun and helps to keep the soil from losing moisture. Research in Michigan, however, found that soil temperatures were lower and soil moisture was higher in the RG,1,30K relative to the MOB,0.33,100K systems.

 First of all, we're talking Michigan, not Texas, so it's entirely possible that a) warmer soil temps can have a positive effect as soil microbes can benefit from the 'free' energy provided by warmer soil, which anyone who gardens in the north can appreciate when it comes to getting plants to grow and b) there's absolutely no quantification of the temperature and moisture levels, so there's no indication of whether or not they are anywhere near the point of being harmful and, c)

Conclusions from their research must be drawn cautiously until more replications of these treatments can examine these effects over more soil types and landscape positions

the guy pretty much admits that it's a crock of shit.

Mulch on the soil surface – With all that trampling of forage, one would assume that a mob system would result in more residue on the soil surface. However, work in Nebraska indicated that the MOB,0.5,200K resulted in an average of 2 percent loss in litter mass, which was similar to the non-grazed control.

Meanwhile, the RG,15,7.5K and RG,10,5K systems resulted in a 7 to 12 percent increase in residue on the soil surface (Figure 3).

 Actually, if one has an understanding of microbial activity in the soil and the benefit of litter mass with regards to that microbial activity, one would assume that, when the use of MOB grazing results in 56% of the pasture being trampled compared to the 32% and 19% as seen in Figure 2, yet the resulting litter mass experiences a 2% loss in litter mass, the law of conservation of mass would imply that the high amount of trampled litter is being very efficiently incorporated into the soil as organic matter by the microbes.  It doesn't just disappear.

Soil compaction – With those ultra-high stocking densities, some worry that excessive soil compaction may occur as a result of the hoof traffic. Here again, the research does not provide clear answers.

 It's late and I'm ready to punch this guy, so let's just go with "does not provide clear answers", even though he then goes on to point out that MOB results in more compaction in MI because, let's face it, we all know he's got an axe to grind at this point.

Very limited research data are available on this aspect, but the research in Michigan found that soil OM was higher in the RG,1,30K relative to the MOB,0.33,100K system at each increment in a 12-inch soil profile. Again, one should be cautious with conclusions until this research can be replicated across other soil types and landscape positions.

 So, not only does he preface and postface his statement, he still wants to say that the OM was lower in the MOB grazing, though he won't tell us by how much (so, not much), nor if it's significant (it's not; you don't preface and postface if it is).  I think his mother ran off with a MOB grazer and he's still emotionally scarred by it.

The greenhouse gas emissions from the soil of the RG,1,30K pastures were 50 to 70 percent less than the MOB,0.33,100K system per animal unit. This is largely because the RG,1,30K and MOB,0.33,100K systems in their experiment were different in the stocking rate.

 This whole section is a jumbled mess.  There's no explanation of the testing parameters or timeline.  Are we talking about short-term emissions, because the high impact of MOB will expose more volatile elements in the short term compared to lower stock densities but, as I've pointed out, the long-term carbon sequestration of MOB grazing should be accounted for, as should the sequestration of methane and nitrous oxide from microbial and insect activity.

Profitability

 There's not enough info given to analyse this.  I suspect profit is listed on a per head basis, but it's not clear.  MOB grazing will almost certainly result in a lower profit per head, but it maximizes profit  (meat production) per acre, especially over a longer time period.  The way to maximize your per head profitability is to drop your stocking rate down, letting a few cows selectively graze your entire acreage.  Without knowing what the chart is actually supposed to represent, it's impossible to critique it.

Weaknesses and Data Gaps

 I like this.  Can we just say that encompasses the whole 'article' (I use the term loosely)?  

More importantly, most of the studies to date set the stocking rate equal across treatments. Research has not yet determined if rotational and mob grazing management systems differ in their optimal stocking rates or in carrying capacity over the long run.

 Every beef producer that uses MOB grazing seems to carry far more cattle per acre (stocking rate) as well as stocking density.  The consensus seems to be that you will see poorer performance per animal but the greater number of head per acre more than makes up for it, resulting in a higher profit per acre.  Additionally, many experienced practitioners of MOB grazing carry 3-5 times the stocking rate of their non-MOB neighbours and are unable to get enough cattle to utilize the forage they have available.

I know most of you are thinking That's great, Timtohy, but tell us more! (I should really change my user name to TL;DR).  There's a quote that Mark Twain attributes to Benjamin Disraeli

There are three kinds of lies: lies, damned lies, and statistics.

and it's quite apropos.  There is a significant number of people who aren't comfortable with numbers, regardless of their intelligence.  Some people like to hurl 'statistics' at them in order to baffle them.  Ancel Keys published the "Seven Countries Study" that linked dietary fat to heart disease.  This study became a significant pillar of the nutritional guidelines, though it seems that Keys completely omitted 15 countries where the diet and heart disease didn't fit his hypothesis.  Recently, there's been this graph floating around, purporting to prove that the US is actually experiencing a cooling trend:

 
I highly suggest you check out this article Why is it so Easy to Deceive People for a fascinating explanation of how to use stats to lie.  I feel like this mob grazing article, if not nefariously intended, is at best horribly conceived and misleading.

tl;dr:  I disagree with the article

Tim,

Good running commentary. I like the baseline skepticism. I don't know this magazine, probably a freeby they send you when you shop the seed n' feed. The fact that he doesn't give a citation to the different reference studies is a big tipoff. Still, it is probably not the venue that most people expect that.

I found this gem in the commentary:
This is a nice summary of the existing (very scarce) literature.

To quibble a bit: I read the 3 papers from the the Michigan study and it doesn’t seem like a good comparative of Mob-stocking vs lower density rotational grazing.

First, the non-mob system had irrigation, and the mob didn’t.

Second: after only 3-4 years, the rotational system had 18.7 t/ac more Soil Carbon and 1250 lbs/ac more soil nitrogen than the exclosure. This is not possible (>300 lbs N/ac/yr accumulation due to grazing management??!!!) and likely indicates that there were substantial soil differences before the experiment started (the researchers didn’t do baseline sampling.) Comparison to rates of gain from converting to pasture would be misleading, because these research sites were pasture for more than 20 years previously.

If we exclude that study, we are left with the results from Arkansas and Nebraska, which while interesting, are hardly enough to make broad conclusions.



Those are a couple of significant points. One pasture irrigated and one not? Come on!  

If someone can point me to the source articles in Michigan I would appreciate it, I can get them if I have some more data than just the state. Every study has weaknesses, and I am willing to move beyond that. I plan on repeating it anyway in my environment. I am glad that some of these are done, maybe I will take a whack at writing something for these guys in rebuttal, although this is a two year old article.

Good catch, Tj.  I know it's incredibly hard to do studies with large numbers of livestock as comparing farms and even pastures within farms is so hard to do.  I think the minimum would be to include soil testing before and after and the irrigated/non-irrigated is just irresponsible as far as doing a study.  That limitation (probably all of them) should be listed right off the top, but it also blows the whole study out of the water.  

A couple of the other comments (I wouldn't have realised there were comments if you hadn't pointed it out) show confirmation bias.  People, myself included, have a propensity to agree with studies that agree with our opinions.  Most scientists have a middling understanding of statistics (better than the general population, but poor compared to statasticians) and a very poor understanding of proper experiment design, at least from my experience with studies.  I think more peer reviews should start with an unbiased statistician's evaluation of the experiment design; in fact, each experiment should have that before being conducted.  It really grinds my gears when crap science is presented to people and they base real-world decisions on it.

 

Carson Albright wrote:.... that people do tend to exaggerate or over emphasize the benefits of things online, and was wondering if Mob grazing is one of those cases.

Thoughts?

I do think this happens and is a fair statement. I’ve been reading about grazing, mob grazing, rotational, just trying to soak up as much as I can before I bring any cows onto my farm. There’s one commonality that I think holds true, and that is mob/rotational grazing is better for the soil, forages and cows than unmanaged grazing or letting a herd of cows have free reign over a huge area. I know managed grazing conditions vary from farm to farm and by region to region and are very difficult to compare, especially when trying to write some sort of scientific study on grazing, which by default includes nature, which has tons of vairables like weather that are out of control don’t repeat themselves consistently year to year.

As far as unmanaged grazing goes, it happens a lot in my area, and I see over grazed pastures full of unpalatable growth and farmers think the answer is to spray to kill the weeds and fertilize to get the grass to grow. Having a herd of unmanaged cows results in them eating mostly just the grasses, all the time. In spring, as soon as any new growth happens, the cows are right there nibbling off the tender young growth, and that means the grass hardly gets a chance to capture sunlight and grow more roots, which in turn grows more grass faster. This leaves the uneaten “weeds” to grow and capture tons of sunlight, without any neighboring grasses to compete and shade them out to reduce the “weed” growth. High density daily rotated grazing means the cows eat grass and also some of their less favorite forages without over grazing, and with the grasses left somewhat tall and not nibbled short, there’s good grass blade surface area to capture solar energy and regrow strongly which also helps outcompete undesirable things growing in pastures.  Sometimes I want to grab the local farmers, shake them, and say “can’t you see man?! There are better ways!” But that’s the wrong way to go about it and it’s hard to get people to change, especially when it’s “the way they’ve always done it”. I really hope that after a few years of doing mob grazing on my farm, I will get my grazier neighbors curious about my healthy pastures and cows and get them asking me questions, so I can explain my techniques and offer to help and guide them for free to better pasture management, and then they’ll tell their friends, and so on and so on, and the adoption of ecological pasture management will be exponential as graziers abandon old ways when they realize they can grow better pasture forages and improve the soil without the purchase of annual poison and petroleum fertilizer applications. That's money in the bank, and almost everyone can relate to that.

As a guy that has mob grazed, and now I do not, I will say that the problem with this sort of stuff is that you read it, then feel compelled that it is all true due to the scientific aspect of it.

It is all bullshit. Both for and against.

This is the skinny on Mob Grazing. It works, but it is an incredible time-suck. Honestly, I have better things to do then constantly move fence. Is it beneficial by doing so? Sure...but I get the same results from spending a few hours on a tractor and bushogging my field.

For the person who is committed to this sort of thing, and bitter against burning a few gallons of diesel fuel, I can fully understand their passion. Myself, I got the organic matter in my fields already, and having parasite free sheep is important to me; giving them more land in which to graze really helps with that. So I am not hard pressed for the benefits many are looking for.

I do have mutiple fields in wire, and can swap sheep from pasture to pasture easily, and do; but I do not mob graze under a tight scripted way based upon grass growth, and pounds of sheep on the hoof per acre like I used to. I just kind of split the difference between Mob Grazing and Set-stocking, and I am fine with that compromise.

Travis Johnson wrote:but I get the same results from spending a few hours on a tractor and bushogging my field.

I have my doubts that your tractor poops fertility as it's out in the fields

All humor aside, one thing I've learned from talking to farmers in the area and good people on premies is everyone does what they do differently, and does what works for them. I know very little about mob grazing or traditional grazing of sheep and have only been focusing my learning on cows. I imagine both the amount of poop and the biological profile is different from a 200 or 300 lb sheep compared to a 1500lb cow or an even larger bull. I know both are ruminants and have four stomachs, but there's really no other comparison since they are two different species. Both are in the in the classification family of Bovidae but the similarities end there and are each in different subfamilies, genus and species. I do know that cows graze by tearing the grasses and other forages with their tongue and sheep bite using their teeth. It seems sheep graze closer to the soil, leaving less grass behind to capture sunlight and recover where as cows are somewhat limited to how close to the soil they can graze, leaving taller grass behind after grazing to capture more sunlight and recover a little quicker.

Travis, to the only guy commenting who really knows what he is talking about- thanks! The practical cannot be shaded out by the theoretical.

I totally get the time factor. I spend around an hour a week moving the chicken paddock. It would be maybe an extra 10 minutes with twice the chix, and maybe another hour with ten times the number. Scale really matters. If you didn't see it with several hundred sheep, I'm thinking I will be frustrated with ten. I just hate mowing snakes and turtles honestly. Ironically my brother does rotationally graze and he still mows because the ticks are so bad. And when stuff is really growing fast, he mows to keep it from seeding and keep it at boot or below. I started scything, but I really can only keep up a couple acres that way, and stuff still seeded out because it grew a foot in a couple weeks.

Only question I have with the more selective grazing is do you see an increase in noxious weeds and unpalatable stuff? Thats my biggest concern.

I am not really sure you understand what I am doing James. My tractor does not poo manure of course, but my grazing sheep certainly do. What I am doing is mowing my pasture after my sheep graze it. Mob grazing just means you add so many animals to a given acreage, that they are forced to eat all the sward, not just their preferred type of grasses. I do not load up a given acreage as much, so my sheep eat what they prefer. What they do not eat, I mow.

Mob grazing does not change how much manure is distrubuted because it does not matter if 100 sheep graze 10 acres, but are moved 3 times, or 100 sheep graze 10 acres and are moved 15 times; the same amount of manure is produced in a given year for the same ten acres! I still am moving my sheep from pasture to pasture, I have too, because otherwise they would load up on parasites. And I am still getting manure on the pasture, I am just using my tractor to do the clean-up of grasses they do not like.

You are correct that a sheep grazes closer to the ground than a cow, but how much sward is left before a flock/herd is moved, depends on the farmer, and not the sheep/cow. Left too long, cow or sheep, the paddock will be overgrazed.

The size of the animal has no bearing either. Everything in grazing is determined, not by the animal species on the land, but rather a common donominator called ANIMAL UNITS. An animal unit is 1000 pounds. It may be 10 calves that weigh 100 pounds per head, 5 sheep that weigh 200 pounds per head, of 1 yearling steer that weighs 1000 pounds, all equate to one animal unit. 5 sheep, 20 lambs, or 10 calves all poo the same amount of manure since ruminants poo 85% of what they eat back out.

Since the carrying capacity of a given field is given in Animal Units, from that a farmer can determine how many animals they can graze. Generally the limiting factor for animal units is NOT based on what they eat, but the poo they put out. How mach manure a given field can safely accept without producing contaminated run-off is the biggest issue, and is based on sward, soil type, slope, etc. If that sounds odd, it should not; again, when livestock are moved from a paddock is based on what is left for grass. If a farmer leaves them too long, and they are starving, the farmer is losing weight gain, and thus losing money. But if they contaminate a given area, then that goes into streams, and affects everyone. The USDA is REALLY concerned about that.

I say all this so you can understand the only thing mob grazing does: forces animals to eat grasses they normally would not want to. Rather than move temparary fencing, I just clean up the left over grasses and weeds with my tractor. I chop and drop. People without tractors, or those who want to use animals to do teh same thing, moves fences.

Move fences all grazing season, every day for 15 minutes per day?
Spend 8 hours mowing the pasture twice a year?

There is no wrong answer, just preference.

Tj Jefferson wrote:Only question I have with the more selective grazing is do you see an increase in noxious weeds and unpalatable stuff? Thats my biggest concern.

Yes!

But nature is in my favor on this. Noxious weeds seed much later than desirable grasses, so I bushog (called clipping my pastures), before they go to seed. That is why here in Maine, I must clip my pastures twice per year. The key is mowing at a height that is above the second crop coming in.

I am in NO WAY mowing grass, I am knocking down the noxious weeds before going to seed, if that makes sense. Over time this encourages desirable grasses to thrive, and noxious weeds to be stunted, and not allowed to take root.

It is a cross between chop and drop, and grazing.

This is really interesting. I've read a lot on mob grazing, but Travis' arguments seem very convincing. I wonder if anyone has further thoughts on this? Thanks and best wishes

Hi Lu,

Welcome to Permies.

Lu Kbraun wrote:This is really interesting. I've read a lot on mob grazing, but Travis' arguments seem very convincing. I wonder if anyone has further thoughts on this? Thanks and best wishes

I'd say Travis is right, but that doesn't mean that what you're reading about mob grazing can't be valid at the same time.

If you've read any of Gabe Brown's work, you may have heard of his principles of soil health. The 5 principles are: 1. minimize disturbance 2. armor on the soil surface 3. living roots in the soil 4. diversity of species 5. animal integration

However recently he has turned that into 6 principles. Now the #1 principle he always tells people is: know your context.

This is perhaps the most important principle of all. The problem with the study linked in the OP, and so many other scientific studies, is that they don't take into account context. Often it is impossible to. Which is why when many studies try to replicate the efforts of people such as Gabe Brown or Masanobu Fukuoka, two farmers who have come to essentially the same conclusions despite radically different circumstances, they end up with contradicting results. Going off of these studies, holding them in higher regard than people's experience since science is supposed to be objective, it's easy to dismiss them as quacks. But there are certain things that simply cannot be deduced via the scientific method. They can only be deduced by personal observation.

Another reason these studies often fail to reinforce the experiences of individuals is they don't really understand what the individuals were doing, and so they improperly try to apply the exact methods that they used in an inappropriate context. With Fukuoka, after first reading his book I remember reading about studies that attempted to replicate his findings, all of which failed to and concluded that what he was doing just doesn't work. As such, I wondered if what he preached was really legitimate, even though it made so much sense. Since then, there have been countless studies that back up what he was telling people since the 70s, as well as countless individuals who independently discovered the same principles as he did even in much different contexts. The important thing is not the exact method, it is the principles we follow and how they apply to our context.

Mob grazing is not just about having a high stocking density. It is about maximizing impact when it's most needed and still following the other principles of holistic management, such as taking and leaving the right amount of forage and allowing the right amount of rest. Gabe Brown, and his partner Allen Williams, although they may talk about mob grazing, have never said to do mob grazing all of the time. They push what is called Adaptive Grazing. This is about using the right kind of management decisions according to your context and what you observe, while following the soil health principles.



The people you typically see using mob grazing to great effect are large-scale ranchers who are running hundreds of heads of grazing animals across hundreds to thousands of acres. The great thing about rotational grazing is that it scales up so magnificently. I have personally observed, from working on different farms, the contrast between moving 5 cows, 20 cows and 100 cows. In many ways, it's actually easier to move the larger groups. And setting up paddocks for them hardly takes longer than the smaller groups. For the larger groups, mob grazing can very much make sense. For just 5 cows, the experience will be similar to Travis's. It just isn't worth the effort.

Point being, if you only have a small group of animals or even just one cow, you should still rotate them through your pastures. But it's pretty pointless to replicate one-to-one the guys who are moving 100 head twice a day at high stocking density. That doesn't mean you still can't learn from them. I do believe that a larger herd is more efficient in just about every way for building soil. Still, I have seen the amazing effect that even a basic rotation of a single cow can have on soil fertility in just a few years. And it's a great way to learn when you are merely keeping a cow while working a full-time job. Maybe some day you can use the experience to do it at a much greater scale.

I've never been a strong advocate mor mob grazing. That said, it does have its place and does have useful aspects to it. It all depends on what you are trying to accomplish (THE OBJECTIVES) with mob grazing. It also depends, I think, on the ecosystem that the mob grazing is being applied in. I do not think anywhere east of the Mississippi (roughly) is suited to mob grazing, largely because of the relative even/temperate distribution of rainfall. Elsewhere, where rainfall is much more seasonal (the 'west') and a good portion of Africa (where mob grazing has its roots) mob grazing is effective and has its place.