Naturalisation in Extra-Tropical Countries. 15 



bending to the ground and striking root ; its autumnal tint gives 

 quite a picture to the landscape. The stem is sometimes 40 feet 

 long, but slender. Found to be hardy as far north as Christiania or 

 even Nyborg, in lat. 70 10', where the mean annual temperature is 

 29 F., the highest 95 and the lowest- 40 F. [Professor Schue- 

 beler]. The wood is heavier and of closer grain than that of A. 

 macrophyllum [Dr. Gibbons] ; very tough, used for helves and many 

 implements [Dr. G-. Dawson"]. 



Acer dasycarpum, Ehrhart. (A. saccharinum, Linnd. ) 



The Silver-Maple of North- America. Requires a rather warmer 

 climate than most other American maples, but has proved hardy in 

 Norway as far as 59 55' N. [Schuebeler]. Height reaching 50 feet ; 

 stem sometimes 9 feet in diameter. Much praised for street-planting ; 

 growth comparatively rapid. It produces no suckers, nor is the tree 

 subject to disease. A most beautiful tree, with a stout stem and a 

 magnificent crown, growing best on the banks of rivers with limpid 

 water and a gravelly bed, but never in swampy ground, where the 

 Red Maple takes its place. Excellent trees can be raised from 

 cuttings of this and some other congeners. The wood is pale and 

 soft, of less strength and durability than that of many of its con- 

 geners, but makes excellent charcoal. It may be cut into extreme 

 thinness for wood-paperhangings [Simmonds]. The tree also yields 

 maple-sugar, though not in such quantity as A. nigrum. With other 

 maples, an early yielder of honey to bees. The specific name, given 

 by Linne, has priority, but does not apply to the best Sugar Maple. 



Acer macrophyllum, Pursh. 



Large Oregon-Maple. From British Columbia to Northern Mexico. 

 A fine shade-tree of quick growth ; sometimes reaching a height of 

 90 feet ; stem attaining 16 feet in circumference ; delights on banks 

 of streams. The inner bark can .be utilised for baskets, hats and 

 superior mats ; the hard and close wood is a substitute for hickory. 

 It is whitish, beautifully streaked when curled. Splendid for orna- 

 mental work. Maple-sugar is also manufactured from the sap of 

 this species [Sargent]. 



Acer Negundo, Linn. (Negundo aceroides, Mcench.) 



The Box-elder of North- America. Hardy in Norway to 59 55' 

 N. [Schuebeler]. A tree, deciduous like the rest of the maples ; 

 may attain a height of about 50 feet ; it is rich in saccharine sap ; 

 according to Vasey it contains almost as much as the Sugar-maple. 

 In California it is used extensively as a shade-tree. Cultivated, the 

 stem attains about 8 inches in diameter in 8 years [BrewerJ. 

 wood is yellow, marked with violet and rosy streaks [ Simmonds J. 

 Rate of growth for stem-girth in Nebraska about 2 feet in fqurte 

 years [Governor Furnas]. 



