752 The Rhododendrons 



II. THE RHODODENDRONS 



GENUS RHODODENDRON LINN/EUS 



HODODENDRON comprises about loo species of shrubs, and a few 

 small trees of the northern hemisphere, about lo species being indig- 

 enous to North America. They are of Httle economic value, although 

 the leaves and bark have at times been recommended as medicinal 

 agents; their chief value lies in the great beauty of the plants, especially when in 

 flower. 



They have persistent, alternate, thick, leathery, entire leaves. The flowers are 

 large and very showy, in terminal clusters, perfect, unfolding from large cone-like 

 winter buds. The calyx is persistent, 5-lobed or 5-parted; the corolla is nearly 

 bell-shaped, variously colored, 5-lobed, slightly irregular, the 3 upper lobes 

 being more spreading than the 2 low^er; stamens usually 10, exserted, declined or 

 equally spreading, somewhat unequal; filaments white or colored; anthers attached 

 on the back, opening by apical pores, without appendages; ovary mostly 5-celled; 

 style long and slender; stigma capitate or lobed; ovules numerous. The fruit is a 

 dry, mostly 5-valved linear-oblong capsule, with numerous small seeds. 



The name is Greek, meaning a Rose tree; the type species is R. Jerrugineum 

 Linnaeus, of the Old World. 



Eastern: leaves very thick; pedicels glandular or pubescent. 



Calyx-lobes oblong or ovate, obtuse, 4 to 6 mm. long. i. R. maximum. 



Calyx -lobes triangular, acute, i to 2 mm. long. 2. R. cataivbiense. 



Western: leaves not so thick; pedicels smooth 3. R. calijornicum. 



I . GREAT LAUREL Rhododendron maximum Linnaeus 



This handsome small evergreen tree or shrub is also called Rhododendron, 

 Laurel, Big laurel. Big leaf laurel. Deer tongue laurel. Mountain laurel. Rose 

 bay laurel. Dwarf rose bay tree, and Spoon hutch. It occurs from Nova Scotia 

 and Ontario southward in the mountains to Georgia and Alabama. It is rather 

 rare at the north, where it occurs but sparingly in swamps; southward in the moun- 

 tains it is abundant along steep stream banks and in hilly woods, reaching a 

 maximum height of about 12 meters, with a trunk diameter of 3 dm. 



The often bent trunk is usually short; the branches are stout, stiff and crooked, 

 often interlocking and forming dense thickets. The bark is about 1.5 mm. thick, 

 covered with red-brown scales. The twigs are stout, round, covered with stiff 

 hairs, green, becoming reddish gray. The winter leaf-buds are axillary, formed 

 the previous summer. The flower-buds are pointed, 3.5 to 5 cm. long. The leaves,, 

 which remain upon the branches for two or three years, are thick and leathery, 

 oblong-oblanceolate, 10 to 25 cm. long, sharp or abruptly taper- pointed, wedge- 

 shaped or rounded at the base, entire and sHghtly revolute on the margin, more 



