Because beef feed is the most water efficient crop that can be grown in many areas. Cattle have four stomachs, they are very efficient at turning grass and similar crops into calories. They are inefficient at turning energy dense foods such as grains into calories.
In other words, if the most environmentally friendly crop for an area cannot be eaten directly by humans, the most environmentally friendly thing may be to use cattle to turn them into calories that can be eaten by humans.
A large portion of North America used to be grassland fed upon by Bison. Range cattle have a very similar ecological footprint to Bison. By that measure, they are much more "natural" than any other food (except perhaps bison or mastodon). Pasture and hay land is rarely/never a monoculture, it is rarely/never sprayed with chemical. (Which is much more environmentally friendly than the organic alternative, plowing). It's also rarely irrigated. You're much more likely to find wild life on pasture and hay land.
As far as I'm aware, most beef cattle in North America is free range and grain finished. In other words, they eat hay (or their mother does) for most of their lives and are only fed grain for a couple of months before being slaughtered or on especially cold winter days.
It mostly depends on the relative prices of corn and beef. Corn is heavily subsidized in the States, so an unnatural amount of it is fed to cattle.
>Most of the farms with livestock were farms with pastured livestock types and few other livestock, represented by 707,365 farms (54 percent). Farms with few livestock numbered 361,031 (27 percent), farms with confined livestock types numbered 237,821 (18 percent), and farms with specialty livestock types numbered 8,834 (0.7 percent).
>Overall, farms with pastured livestock types and few other livestock accounted for only 17 percent of all livestock sales
Of course, farms w/ confined cattle may raise free-range cattle as well.
>Farms with confined livestock types accounted for 99 percent or more of all animal units on all farms with livestock for each of fattened cattle, milk cows, other dairy cattle,11 swine, chickens, and turkeys
From skimming. This actually has some pretty interesting data, prolly warrants a more serious look.
Yep. Cattle just don't do well, long term, on grain. It acidifies the stomach(s) which they're not equipped to handle. All cattle in the US is grass fed for the first 2/3 of its life, then moved to grain for most. Mine eat grain as a treat, it's like candy to them. But the primary source of their food is grass. Grass that I would be mowing otherwise (well, my wife - I'm allergic).
In other words, if the most environmentally friendly crop for an area cannot be eaten directly by humans, the most environmentally friendly thing may be to use cattle to turn them into calories that can be eaten by humans.
A large portion of North America used to be grassland fed upon by Bison. Range cattle have a very similar ecological footprint to Bison. By that measure, they are much more "natural" than any other food (except perhaps bison or mastodon). Pasture and hay land is rarely/never a monoculture, it is rarely/never sprayed with chemical. (Which is much more environmentally friendly than the organic alternative, plowing). It's also rarely irrigated. You're much more likely to find wild life on pasture and hay land.