216 



SALICACEiE. 



PoPULUS. 



5. Populus nigra, var. betulifolia. Birch-leaved Poplar. 



Young branches pubescent ; leaves deltoid-rhomboid, conspicuously acuminate, finely 

 crenate-serrate, smooth on both sides. — P. nigra, Michx. fl. 2. p. 244? P. Hudsonica, Michx. 

 f. sylv. 2. p. 114. t. 96. fig. 1 ; Torr. commend, p. 375 ; Beck, hot. p. 323. P. betulsgfolia, 

 Pursh, fl. 2. p. 619 ; Loud. enc. tr. $ shr. p. 825. 



A tree 30 - 50 feet high and 1-2 feet in diameter, with a large spreading head ; the 

 young branches yellowish. Buds brown. Leaves about 2^ inches long, tapering to a long 

 point, serrate at the obtusely cuneate base, as well as on the rest of the margin : petiole 

 rather more than half the length of the lamina, moderately compressed except at the base, 

 which is nearly terete. Aments not seen, but according to Michaux they are 4-5 inches 

 long, and destitute of the hairs that occur in several other species. 



Banks of the Hudson, above Albany (Michaux). I have not seen this species within the 

 limits of the State, and Michaux himself never found the tree except in the locality just 

 mentioned, where it would seem it was not indigenous. Some years ago there were many 

 large trees of this Poplar at Hoboken, on the road leading to Hackensack, but few of them 

 are now left. I have not been able to ascertain their origin. There can be little doubt of 

 the tree being a mere variety of P. nigra ; and according to Mr. Loudon (I. c), Michaux, in 

 1840, was of this opinion also. It is probably not a native of North America. 



6. Populus balsamifera, Linn. Balsam Poplar. Tackamahac. 



Branches terete ; leaves ovate, acuminate, serrate, smooth on both sides, pale and reticulate 

 underneath ; bracts of the ament dilated, laciniately fimbriate, slightly hairy ; stamens very 

 numerous ; ovary ovoid-globose ; lobes of the stigma very large and dilated. — Linn. sp. (ed. 2.) 

 2. p. 1464 ; Michx. fl. 2. p. 244 ; Michx. f. sylv. 2. t. 98 ; Pursh, fl. 2. p. 619 ; Beck, hot. 

 p. 322; Ho6k.fi. Bor.-Am. 2. p. 154. 



Stem 30 - 80 feet high and 1-2 feet or more in diameter. Leaves about 3 inches long, 

 usually more or less ovate, of a yellowish color when young, but bright green above in the 

 adult state ; the serratures small and rather sharp : petiole nearly smooth, the upper half 

 slightly compressed, the lower terete. Sterile aments 2-3 inches long ; the bracts nearly 

 orbicular, light brown, irregularly cut into numerous narrow segments : stamens 40 - 50 : 

 anthers deep purple. Fertile aments finally 4-6 inches long ; the rachis smooth : ovaries 

 on very short pedicels, smooth. 



Banks of rivers and borders of swamps. Oneida county (Dr. Knieskern) ; near Niagara 

 (Dr. Kinnicutt) ; shores of Lake Champlain (Michaux). The localities here given are pro- 

 bably the southern limits of this tree. To the north it is found as far as Great Slave Lake. 

 On the Northwest Coast, according to the late Mr. Douglas, it sometimes attains the height 

 of 140 feet, with a trunk from 9-20 feet in diameter. The buds in the spring are large, 

 yellow, and covered with a fragrant varnish. 



