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this tree attains in Japan. Some of the most valuable of the Lindens 
are hybrids. Attention has already been called in this Bulletin to 
Tilia vulgaris. The Crimean Tilia euchlora is believed to be a natural 
hybrid between T. caucasica and T. caudata. One of the handsomest 
of the Linden-trees in the Arboretum, T. spectabilis, is supposed to be 
a hybrid of T. glabra and T. petiolaris. It is a fast growing tree with 
leaves as large or larger than those of T. glabra but silvery white like 
those of its other parent. A variety of this hybrid called “Moltkei” 
originated many years ago in a German nursery. It is a tree of denser 
habit and darker leaves than T. spectabilis and grows well in the Arbor- 
etum. The Arboretum collection of Lindens has been arranged in the 
meadow on the right hand side of the Meadow Road. It now contains 
forty-five species, hybrids and varieties, and offers a good opportunity 
for the study of these trees, although they are of course too young to 
show their habit at maturity. Many of them, however, have produced 
flowers and ripened fruit for several years, and every year information 
of their permanent value in this region is accumulating. 
The Sorrel Tree, Oxydendrum arboreum, is already covered with flow- 
ers which will open before the end of the month. This tree is a native 
of the southern Appalachian forests. It has deciduous bright green, 
shining leaves which have a pleasant acidulous flavor and in the autumn 
turn bright scarlet, Andromeda-like flowers erect on the branches of 
spreading or slightly drooping terminal clusters, and pale capsular 
fruits which in the autumn are conspicuous among the brilliant leaves. 
In its native forests the Sorrel-tree sometimes grows to a height of 
sixty feet, but as it grows slowly and begins to flower at the north 
when only a few feet high it will probably never attain a great size 
here. It is one of the handsomest, nevertheless, of summer-flowering 
trees which can be grown in New England. There is a group of these 
plants among the Laurels at the northern base of Hemlock Hill. 
The summer-flowering Buckeye, Aesculus parviflora, is already cov- 
ered with its tall narrow spikes of small, slender, white flowers with 
long exserted stamens, and is perhaps the most conspicuous of the 
summer-flowering shrubs, with the exception of Hydrangeas, which are 
hardy in the Arboretum. It is a native of the southeastern states from 
South Carolina to Florida and Alabama, and nowhere abundant it ap- 
pears to be most common in northern Alabama. It has long, however, 
been a favorite in gardens in which it produces stems seven or eight 
feet high and in good soil and with sufficient room spreads into great 
thickets often twenty or thirty feet across. 
Cornus amomum, the Silky Cornel, is the last of the American Dog- 
woods to bloom and flowers can still be found on many of the plants 
in the Arboretum where they have been largely used. In cultivation 
it is not a satisfactory plant unless it can be given sufficient room for 
its wide-spreading branches to extend freely over the ground. When 
crowded by other plants the branches become erect and it loses its real 
beauty and value. To be seen at its best this Cornel should have a 
clear space with a diameter of not less than twenty feet in which to 
spread. It is well suited for the front of groups of trees and shrubs. 
