- American Smoke Tree. Our native Smoketree is one of the more awesome sights both in flower and in fall color that one could imagine. Dirr says, "The bluish to dark green leaves turn a magnificent yellow, orange, amber, red and reddish-purple in the fall. In fact, it may be the best of all American shrub-trees for intensity of (fall)color." Need we say more? It can reach a height of 30', but is more commonly smaller. It is dioecious, with the male flowers being slightly showier than the female flowers. It is quite gawky as a young plant, but as time progresses it ages to a real aristocrat among the garden gems. The plants that we sell are seedlings, so the sex will be unknown. The picture was posted on flickr and was taken at Kew Gardens, England by Stephen Buchan.