Complimentary 
NEW SERIES VOL. VI 
NO. 15 
ARNOLD ARBORETUM 
HARVARD UNIVERSITY 
BULLETIN 
OF 
POPULAR INFORMATION 
JAMAICA PLAIN, MASS. OCTOBER 18. 1920 
The Ailanthus. The Tree of Heaven of the Chinese, which botanists 
now call Ailanthus altissima, although it is still better known as Ail- 
anthus glandulosa, is one of the remarkable trees of the northern hemi- 
sphere. Raised in Europe in 1751 from seeds sent from Peking, the 
Ailanthus was one of the first Chinese trees known in western coun- 
tries. The first Ailanthus was planted in the United States by William 
Hamilton in 1784 in his famous garden near Philadelphia; and in 1804 
it was first planted in New England near Portsmouth, Rhode Island, 
where it is still abundant. For many years little attention was paid 
to the Ailanthus in Europe until it was found that one of the silk 
worms could be successfully fed on its leaves. This discovery led to 
the establishment of great Ailanthus-plantations in France where they 
have succeeded beyond the most sanguine expectations, the best results 
having been obtained in calcareous soil and on the sandy seacoast. 
The date of the first planting in Europe of the Ailanthus as a street 
tree is not known, but when the streets of Paris were generally bor- 
dered by trees in the early years of the second Empire it was largely 
and successfully used for this purpose. As early as 1820 its remarka- 
bly rapid growth, the tropical appearance of its long gracefully droop- 
ing leaves and its freedom from the attacks of insects attracted gen- 
eral attention to the Ailanthus in the United States. It was found to 
flourish equally well in the country and in the streets of New York and 
Philadelphia where it grew more rapidly than any tree which had been 
planted in those cities; and it was believed that a tree had been found 
which would take the place of all others for city planting. So great 
did the popularity of the Ailanthus become in a few years that the 
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