POPULUS 



POPULUS 



2703 



19. acuminata, Rydb. (P. coloradensis, Dode). 

 SMOOTH-BARKED COTTOXWOOD. Tree slender, with 

 smoother and lighter - colored 

 bark than in P. fortissimo: Ivs. 

 long-petioled, rhomboid-lanceo- 

 X late, acuminate, serrate only at 



the middle: pistillate catkins 

 slender. Eastern slopes of 

 Rocky Mts. A well-shaped and 

 attractive tree in cult., the Ivs. 

 long-acuminate and somewhat 

 drooping. P. 

 Tweedyi,Brit., 

 is allied to this 

 species and 

 perhaps a 

 variant of it, 

 with mature 

 Ivs. broadly 

 ovate or some 

 of them even 

 orbicular, and 

 cordate at 

 base. Wyo. 



BB. Petioles and branchlets mostly 

 pubescent (becoming glabrate 

 at full maturity). 

 20. candicans, Ait. (P. Taca- 

 mahaca, Mill. P. ontariensis, 

 Desf . P. balsamifera var. candi- 

 cans, Gray. P. macrophyUa, 

 Hort.). BALM OF GILEAD. ON- 

 TARIO POPLAR. Strong-growing 

 spreading pistillate tree, much 

 planted in Eu. as "the balsam 

 poplar" and esteemed for its 

 vigor and hardiness and the 

 resinous fragrance of its large 

 buds in springtime : Ivs. broad and 

 heart-shaped, very hairy (as are also the twigs), the lf.- 

 stalk usually hairy and somewhat flattened. G.C. III. 

 59:230. Apparently a hybrid, the origin of which is in 

 doubt ; the native tree usually confused with this is P. 

 balsamifera var. Michauxii, and sometimes also the sup- 

 posed hybrid, P. Jackii. Said to be sometimes grown 

 under the names of P. suaveolens and P. balsamifera. 

 It is very different from the balsam poplar in method 

 of growth, as it has none of the pyramidal or spire- 

 h'ke tendency of that species, but usually makes a 

 broad and irregularly spreading top. The Balm of 

 Gilead makes a good street tree, and is perhaps the 

 best of the older poplars for shade, but it is not 

 known how extensively it is planted in X. Amer.; it 

 is probably of European origin. Well-grown trees of 

 the form passing under this name in the U. S. have 

 the darkest and richest foliage of any common poplar, 

 and this character makes the tree valuable in heavy 

 groups about the borders of a place. The top is liable 

 to become open and broken with age, however, and the 

 tree often sprouts profusely. It is not well adapted 

 to smoky and dusty locations, as it soon becomes 

 grimy. 



21. Jackii, Sarg. (P. Baileyana, Henry)- Fig. 3145. 

 A supposed hybrid of P. deltoides var. monilifera and 

 P. balsamifera, found as if native in Mich, and Que.: 

 intermediate between the two parents, with terete gla- 

 brous twigs: Ivs. large, broad-ovate, cordate at base, 

 biglandular, slender-acuminate, the margin with scat- 

 tered deciduous hairs and a translucent border, the 

 under surface pale but scarcely whitish, the petioles 

 channeled but not compressed, 4-angled in cross-sec- 

 tion. G.C. III. 59:231. The buds are less viscid than 

 those of P. balsamifera, and the leaf-serratures are not 

 so sharp. It makes a broad-headed branching tree. 

 The range of this tree is not known. 



3144. 



Populus Lind- 

 leyana above, 

 with angled 

 stem, and P. 

 fortissima be- 

 low. 



22. tristis, Fisch. Small tree with viscid pubescent 

 buds which are often attended by persistent ovate- 

 acuminate stipules: Ivs. narrowly ovate, 4 in. long and 

 one-half as broad, ciliate, acuminate, subcordate or 

 rounded at base. Cent. Asia, Himalaya. 



23. Maximdwiczii, Henry. JAPAN POPLAR. Very 

 large tree, to 100 ft., and 3-4 ft. diam., with densely 

 pubescent pale brown branchlets: Ivs. about 4 in. long, 

 nearly orbicular, oval or broad-elliptic, broadest above 

 the middle, subcordate, cuspidate, pubescent on ribs 

 and nerves of both surfaces, whitish or slightly rusty 

 beneath, finely and sharply serrate and ciliate: fruiting 

 catkins 7-10 in. long, remaining unopened on the tree 

 till late summer or autumn, the caps, glabrous. E. 

 Siberia, N. Japan. Hardy and desirable, making a 

 shapely head and bearing attractive foliage. It is 

 sometimes confused with P. suaveolens. Wilson speaks 

 of this tree as a magnificent poplar, the largest in east- 

 ern Asia, the trunk reaching 5 or 6 meters in girth. 



24. suaveolens, Fisch. (P. balsamifera vars. suaveolens 

 and intermedia, Loud.). A comparatively slow-grow- 

 ing tree of close, upright habit: young branches 

 slightly pubescent above nodes: Ivs. very thick and 

 hard, finely serrate, oval to ovate and ovate-lanceolate 

 in outline, and prominently whitened beneath, com- 

 monly rather small for this group, the margin ciliate, 

 and finely crenate-serrate: twigs hard and cylin- 

 drical. Siberia, Mongolia, China. It is considered to 

 be a valuable tree for hot and dry interior climates; 

 and it also has distinct merit for ornamental planting. 

 It eventually becomes a large tree. The Populus 

 laurifolia and P. sibirica pyramidalis of some Ameri- 

 can nurserymen are apparently variations of this 

 type. P. Przewdlskii, Maxim., is probably a form of 

 this with glabrous branchlets and petioles. P. szech- 

 uanica, Schneid., a common tree in forests of Province 

 Szechuan, W. China, growing 



to a large size: in habit and 

 general appearance resembles 

 P. suaveolens but the branches 

 are more massive and 

 branchlets stouter: Ivs. 

 very large even on old 

 trees, on suckers or 

 very strong shoots usu- 

 ally ovate - elongated 

 and the base 

 either slightly or 

 distinctly cor- 



3145. Populus Jackii. 

 An interesting poplar sup- 

 posed to combine the 

 features of the northeast- 

 ern cottonwood and the 

 balsam poplar ( X X) 



