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LANDSCAPE GARDENING. 
outer bark on the young trees ; when old, it becomes rough, 
furrowed, and greenish. The leaves are light green on the 
upper surface, whitish beneath, very pointed at the end, and 
terminated at the base in an acute angle. The twigs are 
long, flexible, and pendulous ; and the limbs of a brown 
colour, spotted with white. 
The European White birch. ( B . alba.) This species, 
the common birch tree of Europe, is intermediate in appear- 
ance and qualities, between our Canoe birch and White birch. 
The latter it resembles in its foliage, the former in its large 
size, and the excellence of its wood. There is a distinct 
variety of this, to which we have alluded, called the Weeping 
birch, ( Var. pendula ,) which is very rapid in its growth, 
and highly graceful in its form. From the great beauty of 
our native species, this is perhaps the only European sort, 
which it is very desirable to introduce into our collections. 
The Alder Tree. Alnus. 
Nat. Ord. Betulaceae. Lin. Syst. Monoecia, Tetrandria. 
The alder tree is a native of the whole of Europe, where 
it grows to the altitude of from thirty to sixty feet. Our 
common Black alder, ( A . glauca,) and Hazel-leaved alder, ( A . 
serrulata ,) are low shrubs of little value or interest. This, 
however, is a neat tree, remarkable for its love of moist situa- 
tions, and thriving best in places even too wet for the willows ; 
although it will also flourish on dry and elevated soils. The 
leaves are roundish in form, wavy, and serrated in their mar- 
gins, and dark green in colour. The tree rapidly forms an 
agreeable, pyramidal head of foliage, when growing in damp 
