226 Bulletin 68 



western New England to Florida and the Rocky Mountains. Its 

 leaf characters are sufficientlj- outlined above (under P. laurifolid), 

 but it is variable in shape and color of leaves. Some of the forms 

 are fairly distinct in foliage and aspect, and they appear to be 

 associated with particular horticultural names, in the nurseries. 

 Fig. 9 shows a form with ver)- long-pointed and round-based leaves; 

 but itusuall}' bears, also, the typical triangular foliage. Some of 

 the most ornamental specimens of cottonwood are those which have 

 reddish leaf- stalks and midribs. 



Taking all things into consideration, the cottonwood is prob- 

 ably the best of the poplars for general ornamental planting. It 

 grows rapidly and in almost every soil, and yet it possesses an air 

 of strength and durability which most of the poplars lack. Its 

 foliage is always bright and glossy, and the constant movement of 

 the broad rich green leaves gives it an air of cheeriness which few 

 trees possess. The tree has been much used upon the western 

 prairies and in western towns, much too abundantly for good 

 landscape eflfects. The rapid growth of the tree gives a feeling of 

 luxuriance to plantations, even when most other trees appear to 

 be weak or starved. The cottonwood thrives best upon rather 

 low lands, and yet it is generally an admirable tree upon high and 

 dry areas. 



The so-called Carolina poplar is only a verj- luxuriant cultivated 

 form of the cottonwood. As sold by the New York nurserj-men 

 it does not differ otherwise from the wild Populus monilifera of 

 our woods and creek borders. 



There is a golden-leaved form of the cottonwood known as var- 

 iety Van Geertii or var. aiirea. It is one of the best of yellow- 

 leaved trees, and generally holds its color throughout the season. 

 Like all trees of this unusual character, it should be used 

 cautiousl3^ and the best effects are obtained when it is planted 

 against a group of trees so as to appear as if naturally projecting 

 from the other foliage. 



7. Populus nigra (Linn. Sp. PI. 1034 (1753). P. Hiidsonica, 

 Michx. f. Hist. Arb. Amer. iii. t. 10. P. beiidifolia, Pursh, Fl. 

 Amer. Sept. ii. 619. P. Eugenie oi nurserymen). Black Pop- 

 lar, h and 1, fig. i . A European tree of medium to large size, 

 with leaves somewhat resembling those of the cottonwood, but 



