200 LANDSCAPE GARDENING. 



them. There are two sorts of timber known ; viz. the Yel- 

 low and the White poplar, or tulip tree. These, however, it 

 is well known are the same species, {L. tuUpifej-a,) but the 

 variation is brought about by the soil, which if dry, gravelly, 

 and elevated, produces the white, and if rich, deep, and rather 

 moist, the yellow timber. 



It is rather difficult to transplant the Tulip tree when it has 

 attained much size, unless the roots have undergone prepa- 

 ration, as will hereafter be mentioned ; but it is easily propa- 

 gated from seed, or obtained from the nurseries, and the 

 growth is strong and rapid. 



The Dogwood Tree. Cornus. 



Nat. Ord. Cornaceae. Lin. Syst. Tetrandria, Monogynia. 



There are a number of small shrubs that belong to this 

 genus, but the common Dogwood, (Cornus Jlorida,) is the 

 only species which has any claims to rank as a tree. In the 

 middle states, where it abounds, as well as in most other 

 parts of the Union, the maximum height is thirty-five feet, 

 while its ordinary elevation is about twenty feet. 



The Dogwood is quite an ornamental small tree, and owes 

 its interest chiefly to the beauty of its numerous blossoms 

 and fruit. The leaves are oval, about three inches long, 

 dark green above, and paler below. In the beginning of 

 May, while the foliage is beginning to expand rapidly, and 

 before the tree is in full leaf, the flowers unfold, and present 

 a beautiful spectacle, often covering the whole tree with their 

 snowy garniture. The principal beauty of these, consists in 

 the involucrum or calyx, which instead of being green, as 

 is commonly the case, in the Dogwood takes a white or pale 

 blue tint. The true flowers may be seen collected in little 

 clusters, and are individually quite small, though surround- 



