I agree with Bill, wheat is something that is not grown in Roanoke. You'd do better with the tobbacco, some cotton, beans and peas, a bit of corn and apple orchards. Most of the Roanoke valley area is horse and dairy farms, not crops, so open grassy areas with white fencing, barns and animals is much more common and would make more sense to model. I've had good results using thick string dipped in glue and sprinkled with fine ground foam, glued in rows to a dirt "field" to duplicate early growth crops, select a string thickness and foam color that is close to the kind of crop you wish to model. I can make a large field in one evening this way.
Don't use the Pensylvania style barns, most southern barns are less ornate and much more "functional" in construction. Leave off the coupulas, hex signs and dystelfinks and such, just a simple red or white barn with a weather vane is sufficient to duplicate a generic VA barn.