36 
II 
Laburnum alpinum. The large plant of this Laburnum on the right 
hand side of the Forest Hills Road just below the Forest Hills entrance 
is covered again with its long racemes of clear yellow flowers which has 
shown here for many years its value for northern gardens. L. alpi- 
num, which is a native of the elevated regions of southern Europe, is 
usually spoken of as the “Scotch Laburnum” probably because it is a 
favorite in the gardens of north Britain. In those of northern New 
England it is extremely rare. It is hardier than L. vulgare, or as it 
is now called L. anagyroides, a small tree with shorter racemes of 
flowers. This has been a good deal planted in the eastern states, and 
at the north is not always hardy. Occasionally a good specimen can be 
seen in the neighborhood of Boston. There are several varieties of 
this Laburnum which have not, however, grown well in the Arboretum. 
A better plant for New England than L. vulgare is its hybrid with L. 
alpinum, known as L. Watereri or L. ParTcsii. This is a small tree, 
and when in flower the handsomest tree with yellow flowers which can 
be grown in this climate. It blooms about two weeks earlier than 
L. alpinum. 
Cornus alternifolia. This is the handsomest native Dogwood with 
the exception of Cornus florida^ and it has for some reason or other 
proved very .difficult to grow, but fortunately is represented by several 
good native specimens growing in the Arboretum. It differs from all 
the other American Dogwoods as it has alternate leaves and branches. 
Fortunately the Chinese species, Cornus controversa, has proved easier 
to grow and is a plant of first-rate merit. 
Cornus controversa is a widely distributed tree in Japan, Korea and 
western China. Wilson photographed in Szech’uan a specimen sixty 
feet high with a trunk seven feet in girth. In the Cornus Collec- 
tion on the right hand side of the Meadow Road are plants raised from 
seeds collected by Wilson in western China in 1907 and these are now 
in bloom. The largest of these trees is in the Peter’s Hill Nursery. 
This plant was sent here in 1913 by the Park Department of the City 
of Rochester, New York. It is now about twenty-five feet high with 
a short trunk and a head twenty-six feet in diameter. The branches 
are long, crowded and spread at right angles with the stem, drooping 
slightly at the ends, the lowest sweeping the ground. The upper side 
of the branches is thickly covered with flat flower-clusters six or seven 
inches in diameter and raised on erect stems. The flowers are white 
or white faintly tinged with yellow and. are followed by black, shining 
fruits which are eaten by the birds as fast as they ripen. As it grows< 
on Peter’s Hill this Cornel is a magnificent plant and the handsomest 
of the species in the Arboretum, with the exception of the species with 
white floral bracts represented here by C. fiorida and C. kousa. To the 
student of botanical geography C. controversa is interesting as a living 
witness of the relationship between the floras of eastern Asia and east- 
ern North America, for in the genus Cornus with many species there 
are but two with alternate leaves, C. controversa common in eastern 
Asia, and C. alternifolia in eastern North America. 
