10-i SALICACE^;. Populus. 



A bitter principle in the bark causes its occasional use as a tonic in 

 the treatment of intermittent fevers and cases of debility. 



319. Populus grandidentata, Michx. 

 Poplar. 



Nova Scotia, New Brunswick, and west through Ontario to northern 

 Minnesota, south through the Northern States and along the Alleghany 

 Mountains to North Carolina, extending west to middle Kentucky and 

 Tennessee. 



A tree 21 to 24 metres in height, with a trunk 0.50 to 0.75 metre m 

 diameter ; rich woods and borders of streams and swamps. 



Wood light, soft, not strong, close-grained, compact ; medullary rays 

 thin, obscure; color light brown, the sap-wood nearly white; largely 

 manufactured into wood-pulp and occasionally used in turnery, for 

 wooden-ware, etc. 



320. Populus heterophylla, L. 



River Cottonwood. Swamp Cottonwood. 



Connecticut, Northport, Long Island, south, generally near the coast, 

 to southern Georgia, through the Gulf States to western Louisiana, and 

 through Arkansas to central Tennessee and Kentucky, southern Illinois 

 and Indiana. 



A tree 24 to 27 metres in height, with a trunk 0.60 to 0.75 metre in 

 diameter ; borders of river swamps ; most common and reaching its great- 

 est development in the basin of the lower Ohio River ; rare and local. 



Wood light, soft, not strong, close-grained, compact ; medullary rays 

 thin, very obscure ; color dull brown, the thick sap-wood lighter brown. 



321. Populus balsamifera, L. 

 Balsam. Tacamahac. Balm of Gilead. 



Straits of Belle Isle to the shores of Hudson Bay, northwest to the 

 shores of the Great Bear Lake and the valley of the Yukon River. Alaska, 

 south to northern New England, central Michigan and Minnesota, the 

 Rocky Mountains and interior ranges of Montana and Idaho, Washington, 

 and British Columbia. 



A large tree, 18 to 24 metres in height, with a trunk 1.50 to 2.10 

 metres in diameter ; very common on all islands and shores of the north- 

 ern rivers ; in British Columbia generally confounded with the allied 

 P. trichocarpa. the range of the two species here still uncertain. A form 

 with broader heart-shaped haves, white on the under side, rare or un- 

 known in a wild state, very common in cultivation, is var. candiccms, 

 Cray. 



Wood very light, soft, not strong, close-grained, compact ; medullary 

 rays numerous, very obscure ; color brown, the thick sap-wood nearly 

 white 



