Complimentary 
NEW SERIES VOL. Vil 
NO. 15 
ARNOLD ARBORETUM 
HARVARD LJNIVERSITY 
BULLETIN 
OF 
POPULAR INFORMATION 
JAMAICA PLAIN. MASS. AUGUST 2. 1921 
Summer Flowering Trees. Here in the north not many trees except 
Lindens can be grown which flower in summer. These are all valu- 
able, however, for they add interest and variety to parks and gardens 
at the season when the flowers of trees and shrubs are not abundant. 
All the summer flowering trees here are interesting, and the flowers 
of some of them are conspicuous. After the Lindens the first of these 
trees to open its flowers is the Sorrel- tree (Oxydendrum arboreum). 
This tree is the only representative of a genus of the Heath Family 
and one of the few genera of eastern America trees which is not rep- 
resented in eastern Asia. The Sorrel-tree is a common tree of the 
forests of the Appalachian Mountains from southwestern Pennsylvania 
southward; it grows also but less abundantly from southern Ohio and 
Indiana to northern Florida, southern Alabama and Mississippi and in 
eastern Louisiana. Growing under the most favorable conditions the 
Oxydendrum is a tree from fifty to sixty feet high, with a tall straight 
trunk sometimes twenty inches in diameter. The leaves are dark 
green, very lustrous and seven or eight inches long, and the bright 
scarlet of their autumn color is not surpassed by that of any other 
American tree. The leaves are pleasantly acidulous, a character to 
which the tree owes its vernacular name. The white flowers, which 
are shaped like those of an Andromeda, are erect on the branches of 
spreading or drooping clusters, and these are followed by pale capsular 
fruits which are conspicuous in contrast with the brilliant colors of 
the autumn foliage. Flere in the north the Sorrel-tree begins to flower 
when only five or six feet high, and it is not probable that it will ever 
grow here to the size this tree attains in the rich “coves” found on 
the lower slopes of the high southern mountains in which several of 
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