Ted,
A tobacco sled was a sled. It was pulled by horses or, more often around here, by mules. When the tobacco leaves were ready to harvest, the farmer would hitch up the sled to a mule. The mule would pull the sled at a somewhat slow pace, and the field hands would pinch off the tobacco leaves and put them into the sled taking care with the leaves.
The sled was long and skeleton-like--just a floor, braces and crossbeams, as few as possible to make the sled sturdy, but with little wood to bruise the tobacco leaves. In order to keep the leaves from falling out, croker sack (or sometimes burlap) was put all around the inside of the sled forming the four walls. I don't recall whether the croker sack also was put over the floor of the sled, but I wouldn't be surprised since the farmer was trying to keep the leaves from bruising.
It was great fun riding in the sled while the workers pulled the leaves. Once there was a good number of leaves, we kids had to get out--you know, since kids would bruise the leaves a lot more than the wooden frame of the sled.
That's a great memory of mine: riding in the tobacco sled behind the mule--the sound of the runners of the sled moving over the earth--watching that mule trek his large body up and down the rows--turning the tobacco worms inside-out-with my stick. Just great fun.
It's all been modernized now. Just doesn't happen around here anymore. And the tobacco is put into sleds (modern) with vinyl lining--and the tobacco barns look like metal trailers. Everything's practical--and the beauty has been lost altogether.