Making growboxes what material to use?
expensive. Can I use treated lumber for this? I can get 2"x8"x16'
for < $10. Or do you have suggestions of where to get inexpensive
You can use treated lumber, or you can use regular pine. It will last a lot longer if you paint it first - inside and out - with a good exterior paint.
In some places around the world people use a chain saw and cut up their trees. A fabulous garden in Popayan, Colombia is perched on a hillside, with many of the beds held in place with slabs of wood from the big trees they cut down to eliminate the shade.