Botulinum toxins are the most lethal toxins known. For type A toxin, the toxic dose is estimated at 0.001 mcg/kg (Franz 1997); the lethal dose for a 70-kg person by the oral route is estimated at 70 mcg, by the inhalational route 0.80 to 0.90 mcg, and by the intravenous route 0.09 to 0.15 mcg (Sobel 2005).
1 hectare = 2.47105381 acres. .07 hectare= .17 acres per person. about 7500 square feet per person. While this figure produces a result of around 5-6 people per acre, there are plenty of caveats to consider. If the soil is not ideal, increase the land. If the growing season is short, increase the land.
A: Cows will eat 2% of their body weight in hay per day in the winter. You can figure that you are going to need to feed hay around 150 days per year. If your cow weighs 1,200 pounds, she will need 24 pounds of good quality hay for 150 days. So a good starting point would be to have 3,600 pounds of hay per cow per year.