BULLETIN NO. II. 
The Arboretum is often asked to determine the names of European 
Elms and for information about these trees, particularly about the so- 
called English Elms. The subject is complicated for many varieties and 
several hybrids of these trees have been developed through long cultiva- 
tion, and it is sometimes difficult to distinguish hybrids or forms due to 
cultivation from the original wild types of these trees. This difficulty 
is increased by the nearly complete destruction of the original forests 
of western Europe where of most species of trees only planted .individu- 
als can now be seen, and the wild types of the European trees must be 
looked for in the Balkan states or in the Caucasus. 
There are in all Europe four species of Elm trees that can be readily 
distinguished. The confusion in regard to these trees goes back at least 
to the time of Linnaeus who considered that all the European Elms be- 
longed to one species to which he gave the name of campestris. This 
name, however, cannot be used for any one of the four species united by 
Linnaeus as it is impossible to know which of the four he considered best 
deserving of the name. Ulmus campestris , therefore, as a name must 
be given up. This is unfortunate for the name is of old usage and is 
found in all books about trees. 
Two Elm trees grow naturally and spontaneously in Great Britain, Ul- 
mus glabra and Ulmus nitens, and these names, which are the oldest 
which have been applied to these trees, further complicate the situation. 
Ulmus glabra , which is often called the Scotch Elm, is a medium-sized, 
round-headed tree with stout hairy branchlets and large short-stalked 
leaves often three-lobed at the apex, and very rough, especially on the 
upper side, from the short rigid hairs which cover them. This tree can 
easily be distinguished also by the fruit in which the seed is in the center 
of the surrounding wing. It is a native of Scotland and northern Eng- 
land, and extends eastward to the Caucasus, eastern Siberia and Japan, 
where it is represented by a distinct form, the variety Ineterophylla. To 
the Scotch Elm several names have been given. The oldest and the one 
therefore which should be adopted is Ulmus glabra . This is an unfortu- 
nate name for the leaves are rougher than those of any other Elm tree, 
and Ulmus scabra and Ulmus montana which were given to it later are 
more appropriate names. The name glabra , however, as the author who 
first used it states, was given to this tree because the branches are 
smooth, that is because they do not produce the corky wings which are 
developed on the branches of many varieties of Elm trees. The Scotch 
Elm has been sometimes planted in the eastern United States but it is not 
a desirable tree. It does not produce suckers like many other Old World 
Elms, but it bears groat quantities of seeds which are freely blov/n about 
and, growing rapidly, produce innumerable plants which may become 
troublesome weeds. In recent years, in the neighborhood of Boston, the 
leaves of this tree have been destroyed in early summer by the larvae of a 
leaf-mining insect which works entirely under the epidermis of the leaf and 
cannot therefore be reached by an external application of poison. This 
insect is a good botanist and, selecting always this Elm, never feeds on 
any of the other species. Several varieties of the Scotch Elm are com- 
monly cultivated. The best known, perhaps, is the Camperdown Elm, 
the variety Camperdownii. This is the tree with pendulous branches 
which is often planted in suburban gardens where, as the branches grow 
