>Most slaves were needed for about 2 weeks a year for picking season, maybe a bit for planting. The challenge for slave owners was how to warehouse those people at the cheapest per-unit cost for the other 50 weeks.
Depends. A lot of slaves were put to other tasks during the winter, such as low-skilled construction labor. If there was livestock though then there was no change, there is no off-season with cattle, hogs, goats and whatnot. In fact it gets tedious in the winter, you have to move them every day and moving them can be a bitch. If there's a lot of calves and you're by yourself like I was earlier they can be stubborn and you have to time it right while the mamas are distracted with the bait feed. I was chasing them around on the gator earlier today, in fact. I'm glad a lot of the calves are going to be gone soon, I'll tell you that.