DECIDUOUS TREES. 
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good soil. Half the diseases that now attack old elm trees are the 
result of the weakened vigor caused by lack of good fresh soil or 
manure on their roots, which should be put on over the whole area 
that is covered by the branches. A moist surface soil is most con- 
genial to the elm. 
The Red or Slippery Elm. Ulmus rubra., or 
native elm is so overshadowed by the superior size and beauty of 
the weeping elm, that it is rarely planted or seen in open ground. 
It is a tree of a more straggling open head, somewhat similar in 
form, with out-arching branches, but with much larger and sparser 
leaves, and without the pendulous spray of the former. It be- 
comes a tree from fifty to sixty feet high, or about two-thirds the 
size of the white elm. It is of no value for small grounds. 
The Wahoo Elm. Ulmus alata.— This species may be known 
by its two longitudinal ridges of cork-like bark on all its twigs and 
branches, though the white elm and the Dutch elm occasionally 
have varieties that closely resemble it in this respect. It makes 
a pleasing tree of medium size, and grows rapidly. Found wild in 
Virginia and southward. 
The foregoing are American species. 
The following are among the most valued of the great variety 
of European elms grown in England. ’ Loudon remarks that “ the 
elm is remarkable for the aptitude of the different species to vary 
from seed ; so much so that it is extremely difficult to say, in this 
genus, which are species and which are varieties, or even to what 
species the varieties belong. To us it appears that there are only 
two sorts which are truly distinct, viz : U. campestris (the English 
elm) and U. montana (the Scotch elm).” He classes the Ameri- 
can elms as of the same species with the Scotch, U. montana. 
The English Elm. Ulmus campestris . — -The finest trees of 
this species we have seen in this country are on the Boston Com- 
mon, where, in grandeur of branching, majesty of trunk, and 
healthfulness of foliage, they are certainly superior to the white 
elms growing side by side with them. But it must be remembered 
