It took me quite a while to figure out the difference between burrobrush and burroweed (when one isn't blooming), despite various clever mnemonic devices. So I bring you some photos. Look at the links, too, for more photos and info.
|foreground: Burrobrush, background: Burroweed|
|foreground: BW; background (and barely discernable) BB|
|Burroweed: blooms in Fall, yellow flowers. Look now in the canyon.|
|Burrowbrush; blooms in spring, tiny white flowers.|