We ran them last year in 9x6 pasture tractors, had to reduce it to 3 birds each by the time they got to size.
This year we did a bigger tractor, but set the base too low and it proved too hard to move on bumpy ground. So we parked it near a fenceline and used dog kennel panels to fence it in. 20x20 surrounds the lockable shelter.
Started with 10 in there, once gender became obvious we started selling off the girls (we don't eat the girls, instead their sale feeds the boys we keep).
It took them 3 months to take the grass down to dirt. In theory, we could shift the pen down the fenceline to refresh the grass but the next spot over isn't flat and there is a tree in the way. I sold 3 more girls, leaving 4 Toms in there, which has the grass growing back if I keep it watered.
We netted the top to keep them from flying out, since they're Heritage birds.
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