Ailanthus 3 1 



Identification 



In summer the Ailanthus is readily distinguished from all other trees cultivated 

 in England by its large pinnate leaves, which have at the base of the leaflets on each 

 side one or two glandidar teeth. The black walnut, butternut, and Cedrela sinensis 

 have somewhat similar foliage ; but in these the glandular teeth are wanting. The 

 bark of Ailanthus is quite peculiar, and when once seen cannot be confounded with 

 that of any other tree. 



In winter Ailanthus is easily recognised by its bark in trees of a certain size ; 

 but in all stages of growth it is well marked by the characters of the buds and 

 branchlets. 



The buds are alternate, uniform in size, small and hemispherical, and show 

 externally 2 or 3 brown tomentose scales.^ The buds are set obliquely on the twigs 

 just above the leaf-scars. The latter are large, heart-shaped, and slightly concave ; 

 and on their surface may be seen about 7 little elevated cicatrices which correspond 

 to the vascular bundles of the fallen leaves. No true terminal bud is formed ; and 

 at the apex of the twig there is an elevated small circular scar, which marks the spot 

 where the tip of the branchlet fell off in summer. The twigs are very coarse, 

 glabrous, or finely pubescent, shining and brown in colour, with a few plainly 

 visible lenticels. The pith is large, buff or yellowish in colour, showing clearly on 

 section the medullary rays. In Cedrela there is a large terminal bud, and the leaf- 

 scar has 5 cicatrices. The chambered pith of Juglans will readily distinguish the 

 black walnut and butternut. 



Varieties 



Several varieties are mentioned in books ; aucubcefolid, pendulifolia, rubra, and 

 flavescens being recognised by Schelle ; ^ but it is doubtful if any of these are 

 sufficiently marked to deserve recognition. The Ailanthus flavescens^ of gardens 

 was determined by Carriere to be Cedrela sinensis. A form with variegated leaves is 

 mentioned by Koch,* but it is exceedingly rare. The Kew Hand-list only admits one 

 variety, pendula, a form somewhat weeping in habit. 



Distribution 



Ailanthus glandulosa has been only found truly wild on the mountains of the 

 province of Chihli in Northern China ; but it is cultivated in most parts of China, 

 and doubtless was once a constituent of the forests of the northern coast provinces, 

 most of which have been destroyed by the Chinese. I never saw it wild in 

 any of the mountain forests of Central or Southern China. When first introduced 



' A plate showing buds will appear in a later part. * Laubhoh-Benennung, 279 (1903). 



' See article on the " Ailanto or Tree of Heaven " by Nicholson, in Garden, 1883, xxiv. 63, with figure of flowers, fruit, 

 and foliage, and many interesting details concerning propagation, etc. 

 * Koch, Dendrologie, i. 569 (1869). 



