We have a peculiar weed that starts like a flat rosette but by mid-summer branched up to several 12" central trunks with side limbs like small tree. It is kind of grayish green until it dries and turns reddish-brown in late summer. Has many, many little seeds on each branch but no leaves. The most remarkable thing is its very pungent odor. (It's not growing now, so don't have a photo to send). Can you give me a clue as to what it might be?