COMPUMENTARY 
NEW SERIES VOL. IX NO. 15 
ARNOLD ARBORETUM 
HARVARD UNIVERSITY 
BULLETIN 
OF 
POPULAR INFORMATION 
JAMAICA PLAIN, MASS. OCTOBER 11. 1923 
The Arboretum is suffering from the severe drought of the last two 
months. September is reported to have been the driest in the last 
fifty-one years, and, in spite of the exceptionally heavy snowfall of the 
winter, the precipitation for the year is now some eight inches below the 
average. The result of this has been that the leaves which take on 
their autumn colors usually in early October have dried up and are 
already falling from many plants. 
The Autumn Color of Leaves. It does not appear to be generally 
understood that the leaves on different individuals of the same species 
do not assume the same shades of color, and that there is considerable 
variation on different individuals in the time of change. This is well 
illustrated by the collection of Red Maples {Acer rubrum) in the Arbor¬ 
etum. From many of the plants the leaves have changed color and 
have already fallen; from others probably one-third of the leaves have 
fallen and on others the leaves are as fresh and green as they were 
in July, all the plants growing practically under the same conditions. 
The Red Maple tree across the drive and opposite the entrance to the 
Administration Building has been during the past week the most bril¬ 
liant object in the Arboretum. Landscape gardeners who may wish to 
use trees and shrubs for autumn effects can find useful suggestions in 
this tree, for it has been raised from a graft taken from a tree with 
leaves of exceptionally brilliant autumn color. This exceptional color 
has been preserved, and indicates that it is possible to multiply by graft¬ 
ing plants with leaves of unusually brilliant autumn color just as it is 
possible to propagate trees with leaves abnormally marked with yellow or 
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