Carving a Cactus

[Underboss]

The plan is to carve a Cactus that is about 3 feet or so in height (maybe 2 and a half). I need thicker pieces of wood to do this, thin pieces wont make it look proportional or life-sized, and I can't simply buy wood from a local lumber yard, they don't sell 3x3x3 blocks.
So my plan is to buy a log from someone with a woodpile and go to (hard) work carving a cactus out.
Any suggestions?

[Ashbys]

If the wood doesn't matter , you could use 4 *4 * 8 (standard) or 6*6 * 8 ( also standard) as well as 8*8 are standards. Or just contact a mill and order direct or mix them 8*8 center 6*6 arms and 4*4 raised arms. These are or should be mill standards for pine. Well at least they use to be.