HEATH FAMILY 
The ancestry and history of our cultivated Rhododendrons 
are most admirably given by Professor Sargent in ‘‘ The Silva 
of North America.” He says: 
The cultivated varieties of Rhododendrons are of garden origin and mixed 
blood. These are chiefly of four races, Indian Azaleas, Ghent Azaleas, The Ca- 
tawbiense Rhododendrons and Javanese Rhododendrons. The Indian Azaleas 
of the garden are improved forms of A. /mdicwm, a native of China and Japan 
which owes its name to the fact that it was first sent to Europe from India; in its 
native countries it is a variable plant with persistent or deciduous leaves and 
small and usually brick-red flowers ; for centuries it has been cultivated by the 
Chinese and Japanese who value it as a chief ornament of their gardens, al- 
though improvement in the size, form, and coloring of its flowers is due to the 
skill of European gardeners, who, especially in Belgium, have devoted much at- 
tention to this plant. Therace of Ghent Azaleas has been produced by cross- 
ing the yellow-flowered Oriental A. fucwmn with the North American 2. ca/en- 
dulaceum R. viscosum and R. nudiforum, and then by crossing their hybrid 
progeny with each other and with the eastern Asiatic A. s/vense and later with 
the Californian 2. occidenti/e and with PR. arborescens of the Alleghany Moun- 
tains. 
The product of these crosses and of years of careful selection carried on 
principally in Belgium and England is a race of hardy shrubs with fragrant flow- 
ers in colors passing from white through yellow and orange to pink and red. 
The Catawbiense Rhododendrons have been produced by crossing R. cataw- 
diense, a native of the high summits of the southern Alleghany Mountains 
which it sometimes covers with vast thickets, with 2. Poticum, the offspring 
being again crossed with 2. avdoreum and other Indian species with bright 
colored flowers or with the North American 2. mwavimum. The race of Javan- 
ese Rhododendrons, conspicuous for their brilliantly colored flowers and their 
habit of flowering continuously, has been obtained by English gardeners by in- 
terbreeding R. Yavanicum and other Malayan species with persistent foliage 
and yellow, orange, and scarlet flowers. 
SOURWOOD. SORREL-TREE 
Oxydéndrum arboreum. 
Oxydendrum, of Greek derivation, means sour tree. 
A slender tree reaching the maximum height of sixty feet, with 
slender spreading branches and oblong, round-topped head. Ranges 
from Pennsylvania along the Alleghany Mountains to Florida and 
Alabama, westward through Ohio to southern Indiana and south- 
ward through Arkansas and Louisiana to the coast. 
Park.—Gray with a reddish tinge, deeply furrowed and scaly. 
Branchlets at first light yellow green, later reddish brown. 
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