DECIDUOUS TREES. 
361 
poplars — a character that unsuits it for small grounds, and adapts 
it to large spaces where it is desirable to have a quick, lofty growth 
of trees. For some reason, however, the best English gardeners 
prefer the black Italian poplar for the same purpose — a variety or 
species supposed to be a cross between this species and the black 
poplar of Europe. 
This tree has been appropriately named cottonwood from the 
quantity of cotton enveloping its seeds, which in May becomes 
detached and floats in the air in such quantities where the tree 
abounds as to be a great nuisance at that season. 
In its early growth the cottonwood is simply rank, upright, and 
uninteresting ; but after it has reached fifty or sixty feet in height, 
its branches begin to bend gracefully, the foliage breaks into fine 
rounded masses, and it spreads into a park tree of noble propor- 
tions. It should never be planted near dwellings or in streets. 
The Black Poplar, P. nigra^ of England, is said to resemble 
our cottopwood in most respects. 
The Black Italian Poplar. P. 7nonilifera . — It is in doubt 
whether this is, or is not, a native of America. The fact that 
neither of the indefatigable Michaux found it wild in America, and 
that its characteristics unite those of the cottonwood and some of 
the European poplars, makes it probable that it is a hybrid between 
them. In form and vigor of growth it is like the cottonwood. An 
English specimen is recorded as having attained the height of 
ninety feet twenty-five years after planting! This in ’Worcester- 
shire. At the Syon Park, England, there is a tree of this species 
one hundred and two feet high, and about one hundred feet in 
breadth of head. 
The Balm of Gilead Poplar. Populiis catidicajts. — This is a 
tree of great vigor of growth, with large conspicuous buds covered 
with balsamic gum. The leaves are nearly heart-shaped, from five 
to eight inches long, glossy on the upper surface, and downy be- 
neath. The form of the head when young is pyramidal, more com- 
pact than that of the cottonwood, and becomes a spreading tree of 
less height. The leaves appear two weeks later than those of our 
native aspen. 
