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Comment by DiabloD3 | Hacker News Reader

Please stop repeating the falsehood that animal pastures can somehow be transmuted into high yield crops for the human food supply: about 1/3rd of farmland in the US can never be transformed into suitable farmland for that task, and this accounts for most of the land used for pasture.

If we're having problems maintain soil fertility levels now, imagine if we needed 2-3x the fertilizer to transform unsuitable land into still unsuitable land (but now growing human-edible crops) because somebody thought this was a good idea.

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I don't believe the argument is that the acreage for animal pastures would be converted, but rather the acreage for the crops they eat would be converted. Or is that in error as well?

Not at all. Those fields are now fertilized with cow manure, though. Without the cattle, you'd need more artificial fertilizer for the crops you intend to feed humans with.

Would it be good for the environment? Quite possibly. Would it result in more fertilizer available on the market? Not really.

The cows need to consume food which has to be grown to produce manure. They don’t magically produce hydrogen, phosphorus and potassium on their own.

Most commercial cattle aren't pasture fed, they aren't free ranging it in a field eating whatever they forage. Hobby and small farms, sure, but the operations that raise the most heads the cattle generally spend the bulk of their life standing in a dirt pen (a feedlot) eating from a trough. They're then fed a mix of corn, soy, ruffage (grasses).

Here is an example of a feedlot https://www.bilaterals.org/IMG/jpg/33a3ab67aa6bbe3184c0441d2...

The cattle come to a side and eat from troughs like this https://cdn.farmjournal.com/s3fs-public/styles/840x600/publi...

It takes 2.5~ pounds of grain and 1,850~ gallons of water to produce 1 pound of beef.

So why not argue for a return to pasture and grass fed and finished cattle then? A lot more people would be willing to agree with you. Intensive use of feedlots has only been going on since the 60s due to an increased demand for beef. The message should be to moderate our consumption of beef and give the cattle a better life at pasture rather than crammed into a feedlot.

There are roughly 1 billion head of cattle in the world, depending on the soil and climate you need anywhere from 2-25 acres per head of cattle to 100% grass feed them (in areas where this is done, obviously 25 acres of desert isn't going to feed a cow).

Even if we assume an average of 3 acres per head, you're looking at 3 billion acres of land just to keep beef going (never mind the 785 million pigs and 33 billion chickens).

If you entirely pasture feed, you're going to get lower slaughter weights too as their weight at slaughter averages about 1,200 pounds compared with about 1,350 pounds for feedlot animals, you'd end up needing something like 30% more cattle to get the same amount of meat https://awellfedworld.org/grazing/

I guess you just completely missed where I said we could moderate our beef consumption. Try again.

Pretty much everything you hear about "solving" the food supply is going to be lies and misinformation.

The people that know what they are talking about are already in the industry. You are not going to see their opinions because they are busy doing what they can.

The people who actually understand things not politicians, academics, or columnists.

Pasture is not just where animals are held. It is land that grows plants eaten directly from the ground by animals, i.e., grazing. So if pasture land isnt suitable to be crop land, then animals fed by grazing pasture is efficient. And according to my reading of this industry website, nearly half of livestock calories come from this:

https://www.sacredcow.info/blog/qz6pi6cvjowjhxsh4dqg1dogizno...

I think you are talking about fodder i.e., crops grown for animal consumption on land that could be used for crops eaten by people. But the above link says only 8% of livestock calories come from fodder. Another 14% come from grains and other food that could have been eaten by people. But altogether this less than a quarter of the calories livestock consume.

The remaining ~30% of calories feeding livestock come from eating stuff generated by the agricultural industry as human-inedible byproducts, chiefly the crop residue left behind when crops are harvested.

Would great appreciate corrections or clarifications if I’ve misinterpreted the above.

People with little to no experience in industries with razor thin margins don't tend to appreciate how optimized for squeezing out pennies those industries are.

>Another 14% come from grains and other food that could have been eaten by people. But altogether this less than a quarter of the calories livestock consume.

Are you wholly unfamiliar with feedlots? 50% + of the bodyweight of the bulk of cattle in the world comes when they live on a feedlot, where they get 5.5 to 6.5 pounds of feed, via trough, to raise them from 600-900 pounds up to the slaughter weight of 1250-1350 pounds.

Corn (dent, which is still usable for human foodstuffs but is mostly just grown for animal feed) is widely used on the feed lot because you don't need 5.5-6.5 pounds per pound of beef, you only need 2.07-2.24 pounds per pound of slaughter weight. Each pound of dent corn yields about 1,566 kcals so you're trading 3241+ kcal of (fertilized) corn crop for 800-1250 kcals of beef.

So for 1 acre of corn you need 40 to 50 pounds of nitrogen, 1 acre of corn. For the 2020 crop year, USDA estimates U.S. corn yield to be 181.8 bushels per acre. 1 bushel is 56 pounds. So to finish 1 cow to slaughter weight, assuming it's pasture fed to 600 pounds, you're looking at roughly 2.9 pounds of nitrogen fertilizer.

So roughly 2.9 pounds of nitrogen, 1345 pounds of corn, and then factor in the water which is 1-2 gallons per 100 pounds of of bodyweight per day times 12-36 months depending on what fat content is desired in the meat.

Again, we can use less fertilizer, reduce water usage, and better use some current cropland (75+ million acres in the United States alone) for crops intended for human consumption, drastically reduce the risk of new diseases by eliminating hundreds of millions of chronically stressed animal hosts, and to simply restore of them to native species in an area and reduce all of the negative environmental impacts of farming in those areas (runoff, soil depletion, loss of native habitats).

Are you disputing the numbers I gave above or just choosing to concentrate on a particular subset of cattle? I don’t believe what you’re describing is representative of livestock in general.

What he’s describing is absolutely standard practice, and is how beef you buy from a typical grocer is raised.

I don't think the numbers you've selected are germane to the conversation. The point of the discussion is how much land substitution there is between animal feed and human feed. The USDA said that in 2013 48% of the US corn crop was used for animal feed, which translates to unbelievably vast acreage. Your numbers indicate that the corn calories are not 100% of the calories consumed by animals.

https://www.usda.gov/sites/default/files/documents/coexisten...

Well, what it tells us is that corn is a large fraction of the crops fed to animals but a significantly smaller fraction of crops fed to humans.

Indeed, it looks like there are 915M acres of agricultural land in the US, and of which 89.5M (<10%) is corn, which works out to 4.7% of all US ag land being used to grow corn fed to animals. Like, obviously that much land is “vast” on an absolute scale, just like any non-trivial fraction of a nationwide number, but it doesn’t strike me as an obviously unreasonable percentage.

Here’s a pretty good chart:

https://www.arespectfullife.com/2018/08/05/41-of-u-s-land-is...

So if we accept that the pasture range cannot be used for crops, then what we are looking at is the animal feed area (which is both fodder and crops that could be eaten by humans but is eaten by animals). It’s 125M acres, I think, or ~14% of all ag land.

Again, I don't like the way you are using numbers. Your 915M acres figure lumps pasture into cropland, which you are using to make the corn for feed number look smaller.

> So if we accept that the pasture range cannot be used for crops, then what we are looking at is the animal feed area (which is both fodder and crops that could be eaten by humans but is eaten by animals). It’s 125M acres, I think, or ~14% of all ag land.

The Bloomberg article that is the source for your source, disagrees with you and categorizes the livestock feed acreage as cropland. So again, you are distorting the picture to make the animal feed number look smaller. Your own source is saying that more acres of cropland are used to feed animals than people.

Sounds like you are misinterpreting me because I haven’t said anything that disagrees with the Bloomberg article, and in particular I agree more land is used for crops eaten by animals than crops eaten by people.

The amount of land used for pasture is definitely germane to the discussion we were having before you began commenting. See my first comment and the one I was replying to.

If you continue to assume bad faith, I won’t continue the discussion.

Grass fed vs grain fed are two different things. If a cow is at pasture it is generally not eating any crops grown elsewhere, that's the point of the pasture they eat the grass that grows on it. I agree with the argument against feeding cattle a diet solely consisting of grain, this is usually done on a feed lot and it's not good for them or the environment. I'm ok with grain finished with a mixed diet since the animal will spend most of its life at pasture. Cattle do require food during the winter so hay and silage must be made for them but these are made from grasses and vetches that can grow on more marginal land than grain crops and they won't deplete the soil as much especially if they are fertilized using the manure from the cattle. So if you are going to make an argument it should be against purely grain fed cattle, you would actually find some traction among ranchers this way as well.

1/3rd of the US farmland being used for pasture and 80% of global crops being fed to livestock are not mutually exclusive on their own.

Edit: Surprisingly our world in data has a breakdown of land uses (which includes grazing) but not of crop use. This study[0] says that about 40% of global crop use (by calories) is used to feed livestock and that it takes about 3.7 crop calories for 1 calorie of animal product. So yes, there's plenty of saving potential even if we kept all the grazing livestock untouched.

[0] https://iopscience.iop.org/article/10.1088/1748-9326/8/4/044...

it can be argued that they actually are.

if that farmland could be used to make human food, which is a lot more remunerative, they already would.

Cows are human food.

they are in fact the preferred way to use that land, because they are more remunerative than planting crops.

makes sense.

Pasture, that is harvested for straw/hay to feed to cattle, still gets fertilized usually at a minimum with added nitrogen. That nitrogen could be better used in other fields growing crops specifically for humans, never mind the negative implications of the runoff that causes damage elsewhere.

> Low values of embodied crop calories are related to production systems for ruminants based on fodder and forage, while large values are usually associated with production systems for non-ruminants fed on crop products.

Cows are ruminants.

> First, we estimated country-wise feed requirements. We calculated feed required per grid cell for each livestock types in ton per year multiplying regional and livestock-wise daily feed requirements (Haberl et al 2007) with the gridded livestock counts.

Honestly, I'm not very interested in their results after reading this. If they're just estimating based on number of livestock x calories required for livestock along with a bucket of crop yields for an area then this is just paper shuffling. You'll have my attention when you get real numbers directly from the farmers themselves rather than just aggregating 3rd hand information over a grid area.

https://iopscience.iop.org/article/10.1088/1748-9326/8/4/044...

The objection I've usually heard is less about farm land being used for pasture instead of growing crops, and more about the amount of crops that have to be grown to feed the cattle... Growing corn to feed cows to feed humans is massively less efficient than growing corn to feed humans, or at least that's how the story goes.

Is there not an efficiency problem there that we could improve on?

(Not an expert in this area, genuinely curious.)

Sure, but go back to pasture based systems. Cows are a fantastic way to turn grass into human edible nutrients. That will probably reduce the amount of meat on the market, but no where near the drastic levels some people talk about.

All land is not fungible, we need to use the best tools for the job, and that will be a mix of a bit of everything, including animal meat.

Not expert either but from forums, I think its a bit of both. People treat pasture country like it would be good for cropping in theoretical climate discussions, and the more correct growing corn/grain/hay etc to feed cattle to feed humans.

Another factor is cattle feed is often poor quality human food, so the reject stuff. That wheat that was harvested a bit early to avoid storms and no good for the flour is great for cattle.

Also, to the main topic of this thread, I wonder if its good for food security we grow extra crops to feed livestock. If there is a food supply shortage, cattle can go to slaughter and there is plenty of extra corn or other about for humans. We eat less meat for a few years while we fix the supply chains type thing.

The way we see supply shortages from COVID, Id hope we never become too efficient in the food supply chain. The consequence of something creating lower food production is far worse than limited computer chips. Its not a system we want to be over optimised for the good times.

It doesn't need to be turned into farmland, we need to stop using existing farmland to grow feed for livestock, which is where so much of it goes.

that only happens because the kind of crops that are farmed are subsidized, so it's economically advantageous to farm those specific crops.

we should stop subsidizing crops it only incentivize monocultures

I was under the impression that a significant percentage of cattle was not fed purely from pastures. Perhaps this what GP's comment was about?

Correct. The vast majority of US cattle are grain fed/finished.

"If all the grain currently fed to livestock in the United States were consumed directly by people, the number of people who could be fed would be nearly 800 million," David Pimentel, professor of ecology in Cornell University's College of Agriculture and Life Sciences, reported at the July 24-26 meeting of the Canadian Society of Animal Science in Montreal. Or, if those grains were exported, it would boost the U.S. trade balance by $80 billion a year, Pimentel estimated.

With only grass-fed livestock, individual Americans would still get more than the recommended daily allowance (RDA) of meat and dairy protein, according to Pimentel's report, "Livestock Production: Energy Inputs and the Environment."

https://news.cornell.edu/stories/1997/08/us-could-feed-800-m...

To add to that, the argument that animal pastures cannot be used for anything else has been proven demonstrably false time and time again. They are not usable for modern day agricultural monoculture cropland, which is the metric that the studies use and I'm sure the commenter is referring to. That does not mean by any stretch of the imagination that they cannot be rewilded or even transformed into usable farm land again through long term soil regeneration methods such as permaculture farming or effective through growing climate appropriate polycultures.

And I suppose the soil unsuitable for crops ( too much clay, etc) but OK for wild grasses, or rocky terrain would just magically fix itself.

Maybe we should blast to level it, and make new soil then?

Around here, Quebec Canada, few cattle are grain fed, and the land they graze on is rocky, hilly, non crop land.

But, even more importantly, is that there is no food shortage. None. Zero. Nada.

In fact, all around the world, Canada, Europe, farmers are paid not to farm.

I detest it when people try to obtain goals, by using false narratives.

Frankly, yes, they do fix themselves. You'd be utterly shocked at what landscapes look like if we leave them. Having been part of forest regeneration efforts across the UK for the past 8 years - from southern heathlands to rocky Welsh and Scottish outcrops, good for "nothing but sheep" - I can say with all certainty that every part of the country except the most extreme alpine regions is suitable for reforestation or some form of plantation dense rewilding, mooring, wild flower meadow, etcetera. The same can be said of much of Canada and America, with my peers over there having the same results when grazing stops. Hell, the Mongolian steppes are turning to results of goat herding, and the Gobi desert is though to have been cause by the same.

In the UK for example, people are completely ignorant to how the place looked before we levelled it for grazing, viewing the 70% ecologically barren agricultural land (of which 80% of that is used for grazing or agriculture to feed cattle) as the norm and the 2.5% old growth forest as a more novelty, and something strangely "unique to that area". The country was 60-80% temperate rainforest before human habitation, depending on what research you go by.

This video is especially poignant, and really shows the dramatic impact simply doing nothing has: https://www.youtube.com/watch?v=3VZSJKbzyMc

Not every piece of land existing should be used to feed us.

We could reforest the pastures (start reducing CO2 in the atmosphere) and return the land to the wildlife (put a stop to an anthropomorphic extinction).

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