1834 ^^^ Trees of Great Britain and Ireland 



There are small trees doing badly at Glasnevin ; but Mr. R. A. Phillips has 

 seen four thriving trees at Staffordstown, Co. Antrim, the largest of which measured 

 40 ft. by 4 ft. in 1910. 



According to Schubeler, it thrives in Norway as far north as Tromso, lat. 69° 40', 

 and succeeds in the Gudbrandsdal at an elevation of 1350 ft. (H. J. E.) 



POPULUS CANDICANS, Ontario Poplar 



Populus candicans, Aiton, Hort. Kew. iii. 406 (1789); Michaux, Hist. Arb. Am. iii. 308 (1813); 



Loudon, Arb. et Frut. Brit. iii. 1676 (1838); Schneider, Laubholzkunde, i. 13 (1904); Dode, 



in Mem. Soc. Hist. Nat. Autun, xviii. 65 (1905); Gombocz, in Math. Termes. Kdzl, xxx. 115 



(1911). 

 Populus Tacamahaca^ Miller, Gard. Did. ed. 8, No. 6 (1768). 

 Populus macrophylla, Lindley, ex Loudon, Encyc. Plants, 840 (1829). 

 Populus ontariensis, Desfontaines, Cat. Hort. Paris (1829). 

 Populus balsamifera, Linneeus, var. candicans. Gray, Manual, 419 (1856); Sargent, Silva N. Amer. 



ix. 169, t. 491 (1896), and Trees N. Amer. 159 (1905). 



A tree, similar in size and bark to P. balsamifera, but different in habit, with 

 more spreading branches, forming a broad crown of foliage. Young branchlets 

 terete or slightly angled, but without projecting ridges, pubescent. Buds large, 

 reddish brown, sharp-pointed, parallel with the twig, exuding resin ; scales ciliate. 

 Leaves (Plate 410, Fig. 22) variable in size, averaging 5 to 6 in. in length, and 

 4 in. in width, broadly ovate-deltoid ; widest near the base, which is cordate, sub- 

 cordate, or rarely truncate ; cuspidate at the apex ; margin conspicuously ciliate, with 

 coarse serrations, ending in incurved glandular points ; upper surface green, with 

 scattered pubescence, glandular at the junction of the petiole ; lower surface whitish, 

 but usually less so than in P. balsamifera and P. trichocarpa, and with scattered hairs, 

 dense on the midrib and nerves ; nervation as in P. balsamifera ; petiole terete, 

 grooved above, densely pubescent. 



Staminate flowers not seen. Pistillate catkins ; axis covered with stiff hairs ; 

 flowers numerous on short glabrous pedicels ; scales broadly obovate, fimbriated 

 with long thread-like lobes ; ovary glabrous, half enclosed in a deep cup-shaped 

 glabrous crenate disc, and surmounted by two sub-sessile large dilated crenulate 

 yellowish or orange stigmas. Fruiting catkins,^ 6 in. long ; capsule, on a glabrous 

 \ in. long pedicel, with two glabrous tuberculate valves ; the whole catkin covered 

 with the down of the seed after the capsules have opened. 



A variegated form of the species is known, in which the leaves are blotched 

 with yellow. Specimens of this may be seen at Woburn, and in the Glasnevin and 

 Edinburgh Botanic Gardens. 



This species is very distinct from P. balsamifera, and is closely allied to 

 P. ciliata of the Himalayas, from which it differs in flowers, though the shape of the 

 leaf is very similar. 



1 Miller's diagnosis applies plainly to this species ; but his detailed description includes also P. balsamifera. I have, 

 therefore, not thought it desirable to resuscitate Miller's name, though the oldest, for the Ontario poplar. 



2 Described from a tree at Belton, perhaps fertilised by some other species of poplar. 



