I personally have a 1/4 acre that is about 50% grass field and 50% woods. I was going to fence it off, and I was wondering how many would happily romp and feed on the 0.25 acre? I have lots more land I can occasionally walk them to graze on, but that's only a time to time possibility.
6 regular size goats need as much land as 1 cow. So you can probably fit 12 dwarf goat for every 1 cow. You can do a quick google search and find out how much land is need to support 1 cow in your area. If I had to guess I would say 3acre per cow or 0.25 acres per dwarf goat. So you can only sustainable feed 1 goat but you need at least 2 goats.
pygmy goats and fias farms are two sites you need to get really familiar with. Goats are browsers not grazers. They can get along well in small areas and you need a minimum of two since they are very social animals, they do not do well in solitary confinement. Your area of .25 acre will hold up to four nicely, but you will be purchasing feed. It would be better if you could have four .25 acre plots so you could at least move them 4 times a year to keep parasites down.
There is no set answer to how many goats you can keep on .25 of an acre. Each site offers different forage and vegetation density. I don't think you could keep goats on .25 acres and not supplement their feed, unless perhaps you had a small paddock rotation throughout the area and moved them constantly. While at the same time improving the vegetation with additional forage crop plantings and removing hazardous species. Even then I think you'll max out at 2 goats.
If on the other hand you plan to feed imported forage daily and clean regularly you could have a dozen goats in that area no problem.
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