Any energy in sage brush?

Just saw an add by Exxon/Mobil on algae research, and it reminded me of something that has come to mind, a lot, while towing through the West. Have passed through millions of acres of sage brush covered, scrub ground, that was covered with un-told millions of tons of the stuff. Anybody ever heard if it's been studied as a sourse of bio fuel? Love the smell of the stuff, so, it must have a whole bunch of resin in it, which, it seems to me, should be fairly volitile. Of course, I realize that you couldn't just strip the ground clear of it, a junk bush, or not, because the bare ground would have a good chance of just starting another Dust Bowl, but still, the question remains, is there some potential there?