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 R. Indicum, 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. The race of Ghent Azaleas has been produced by cross- 

 ing the yellow-flowered Oriental R. flavum with the North American R. calen- 

 dulaceum R. viscosum and R. nudiflorum, and then by crossing their hybrid 

 progeny with each other and with the eastern Asiatic R. sinense and later with 

 the Californian R. occidental and with R. 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- 

 biense, a native of the high summits of the southern Alleghany Mountains 

 which it sometimes covers with vast thickets, with R. Ponticum, the offspring 

 being again crossed with R. arboreum and other Indian species with bright 

 colored flowers or with the North American R. maximum. 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. Javanicum and other Malayan species with persistent foliage 

 and yellow, orange, and scarlet flowers. 



SOURWOOD. SORREL-TREE 



Oxydendrum 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. 



Bark. Gray with a reddish tinge, deeply furrowed and scaly. 

 Branchlets at first light yellow green, later reddish brown. 



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