Amaranth provides almost a complete diet; is a compete diet with vegetable oil, beans, salt, and a multivitamin. High grow out ratio.
Emergency Seed production
Suppose the U.S. no longer has wheat seed to plant. This could easily happen. The wheat seed that is planted is the same as the crop that is harvested. Companies could decide, for economic or political reasons (similar to going on strike) not to plant the wheat seed, but to sell it off as food instead. How long would it take to rebuild the wheat seed supply?
In the 2016 to 2017 wheat crop year (winter wheat is planted in fall and harvested in late spring), the U.S. harvested 2.3 billion bushels of wheat. A bushel of wheat is 60 lbs. So the total harvest across all types of wheat, not just winter wheat, is 138 billion pounds of wheat. Average yield that year was 3162 lbs per acre. The planted acreage was 50.12 million acres. The average yield was 2753 lbs per acre taking into account crop failures. So for crops that came to harvest, yield was over 3000 lbs/acre. But since there is always some crop failures (in this case it was just under 13%), the yield across all plantings was less than 3000 lbs/acre.
Planting 50 million acres takes 5 billion lbs of wheat seed. And the harvest was 138 billion lbs. So the grow out ratio was actually less than in some cases at only 27.6 to 1, rather than the idealized 30:1 (which is attainable).
If we didn’t have the 5 billion lbs of wheat to plant, how long would it take to rebuild the wheat seed supply?
Starting with one thousand lbs of wheat seed, it would take 5 crop cycles to produce the seed, and a sixth crop cycle to produce the final harvest of wheat for food. There is only 1 crop cycle of winter wheat per year. For other types of wheat, depending on the climate or region of the country, you could get two crop cycles per year. So the time to rebuild the seed supply is 3 to 6 years. And that is only if you can find a 1000 lbs of seed to start.
If you wanted to harvest 138 billion lbs of amaranth, here’s how long it would take:
Starting with one pound of amaranth seed only, the third harvest would produce between 1 billion and 8 billion pounds of amaranth seed, and the fourth harvest would produce between 1 trillion and 16 trillion pounds of amaranth grain. (The grain is the seed; they are the same.) A typical yield is 1000 to 2000 lbs harvested per pound planted.
Now the fourth harvest would not be possible in the U.S. as we don’t have enough cropland. But the point is that we would have as much grain as we had land to plant by the fourth harvest. In other words, we could start eating grain after the third harvest, as long as we saved enough to plant for our target yields in the fourth harvest. If we wanted 138 billion pounds in the fourth harvest, we would save and plant 138 million lbs of amaranth to plant to obtain that fourth harvest. That’s 138 million out of 1 to 8 billion.
The time to get to complete the fourth harvest would be only two years, at two plantings per year. And the amount of food produced would be greater.
To feed the whole planet on amaranth, 183 kg per person per year, you would only need four crop cycles, starting with 1.4 kg (about 3 lbs) of grain. That assumes a 1000:1 grow out ratio. But ratios of 2000:1 or even 4000:1 are possible. At 4000:1, starting with 22 kg of amaranth, you could feed the planet for a year by the third harvest (if you had the land available).