Tree of Heaven 



587 



III. TREE OF HEAVEN 



GENUS AILANTHUS DESFONTAINES 

 Species Ailanthus glandulosa Desfontaines 



EVEN species of Ailanthus are known, all natives of eastern Asia; they 

 are trees with odd-pinnate leaves and large panicles of small greenish- 

 white flowers, the pistillate ones followed by drooping clusters of nar- 

 row samaras. The generic name is modified from an Asiatic name 

 of this tree. 



Ailanthus glandulosa, which is the generic type, is a native of China, known 



also as Chinese sumac, but has become 

 so perfectly established in parts of the 

 northeastern United States and Ontario 

 as to appear like an element of the natu- 

 ral flora, growing not only along roads 

 and near habitations, but often in woods 

 and wild thickets, spreading freely both 

 by suckers and seeds. It sometimes be- 

 comes 30 meters high, with a trunk up 

 to a meter in diameter. 



The bark is thin, gray, slightly 

 roughened, that of young branches and 

 shoots quite smooth. The leaves are 

 from 3 to ID dm. long, stalked, smooth, 

 with 13 to 41 short-stalked pointed leaf- 

 lets, which are ovate to ovate-lanceolate, 

 entire-margined or with i to 4 blunt 

 teeth near the heart-shaped or truncate 

 base, thin in texture and wilting at once 

 after the leaf is picked. The individual 

 flowers are only about 6 mm. broad, but 

 exceedingly numerous; the calyx is 5-lobed, the petals 5, valvate, spreading, the 

 disk lo-lobed, and the unpleasantly scented staminate ones have 10 stamens; the 

 ovary in the pistillate ones is deeply 2-lobed to 5-lobed. The samaras are linear, 

 veiny, twisted, about 5 cm. long, thin, bearing the seed at about the middle. 



The free growth by suckers makes this a weed-tree, often verj' difficult to eradi- 

 cate, coming up year after year even when ruthlessly cut down, and growing 2 or 3 



Fig. 542. Tree of Heaven. 



meters high in a season. 



The wood is nearly white, soft and weak. 



