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nurserymen rarely adopt this method for it takes a little longer to 
produce saleable plants than it does by grafting, but the plants on 
their own roots are so much more valuable than grafted plants that 
no one should ever buy a grafted Lilac. 
Syringa pinnatifolia is one of the Lilacs discovered by Wilson in 
western China which has flowered this year for the first time in the 
Arboretum. The small nearly white flowers in small short clusters 
opened ten days ago; they are less beautiful than those of almost any 
other Lilac, but the plant is of considerable interest, as it is the only 
Lilac with pinnate leaves. It is with the other Chinese Lilacs on the 
path at the top of the bank on the left-hand side of the Bussey Hill 
Road occupied by the Lilac Collection. 
Rhododendron (Azalea) Kaempferi. Plants of this handsome red- 
flowered Japanese Azalea on Azalea Path where they are fully exposed 
to the sun have been in flower for a week, although plants in the shade 
on the northern side of Hemlock Hill will not open their flowers for 
several days. The flowers are very delicate and are easily injured by 
the sun, and it is best to plant this shrub among trees in partial shade 
or on the northern side of conifers. This Azalea has been growing 
in the Arboretum for more than twenty years and is perfectly hardy 
in eastern Massachusetts. Late in May or early in June no other 
shrub makes a more brilliant show of color. 
Buckeyes. The first of the Horsechestnuts, or Buckeyes as the spe- 
cies of eastern North America are called, to flower this year is the 
form of the Ohio Buckeye (Aesculus glabra) from northwestern Mis- 
souri, the variety Buckleyi with leaves composed of seven instead of 
five leaflets. It was followed in a few days by the flowers of the nor- 
mal tree. The Ohio Buckeye is a comparatively small tree which be- 
gins to flower when less than ten feet high, and the clusters of small 
yellow or greenish yellow flowers are not showy. It is interesting as 
the only American species with prickly fruit like that of the Old World 
Horsechestnuts. Different Buckeyes and Horsechestnuts will be in 
bloom for several weeks and among them are some of the handsomest 
of flowering trees. The Aesculus Collection is a large one and has 
been arranged next to the Lindens on the right-hand side of the 
Meadow Road. 
An illustrated guide to the Arboretum containing a map showing the 
position of the different groups of plants has been published. It will be 
found useful to persons unfamiliar with the Arboretum. Copies of this 
guide can be obtained at the Administration Building in the Arbor- 
etum, from the Secretary of the Massachusetts Horticultural Society, 
3(X) Massachusetts Avenue, Boston, from The Houghton, Mifflin Com- 
pany, 4 Park Street, Boston, and at the office of the Harvard Alumni 
Bulletin, 18 Plympton Street, Cambridge. Price, 30 cents. 
