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GREAT LAUREL. 

 Rhododendron maximum, Linnaeus. 



GENUS DESCRIPTION The name Rhododendron is of Greek origin and means Rose tree. 

 It comprises about 100 species of shrubs and a few small trees in the northern hemisphere. 

 About 10 species are native to North America and 1 to Pennsylvania. 



FORM A shrub or small bushy tree. In this State usually a shrub from 5-12 ft. in 

 height, but in the mountains of the South it may reach a height of 35 feet. Stems often 

 twisted, bearing contorted branches which form an irregular round head. 



BARK Thin, reddish-brown, at first close, later peeling off into thin scales. 



TWIGS At first green and coated with rusty pubescence but become smooth during first 

 winter, and gradually turn to bright red-brown. 



BUDS Alternate; leaf-buds and flower-buds distinct. Leaf -buds usually axillary sometimes 

 terminal, dark green, cone-shaped, form in midsummer. Flower-buds usually terminal, cone- 

 shape, 1-li inches long, covered by numerous, overlapping, green bracts. 



LEAVES Alternate, simple, persistent, clustered at apex of branches, ovate to oblong, 

 acute at apex, rounded to wedge-shaped at base, entire on margin, 4-11 inches long, 1J-2J inches 

 wide, thick, leathery, smooth and dark green on upper surface, whitish on lower surface. 



LEAF-SCARS Alternate, slightly raised, conspicuous, rounded at base, slightly depressed 

 at top, with several bundle-scars arranged in a U-shaped line. 



FLOWERS Appear about June after the new leaves are fully developed, are arranged in 

 umbel-.like clusters about 4-5 inches in diameter and borne on glandular pedicels. Individual 

 flowers are perfect, pale rose to white in color; upper petals marked by yellowish-green 

 dots. 



FRUIT A dark reddish-brown capsule about 5 of an inch long, which persists until the 

 following season. Capsules split open lengthwise liberating oblong flattened seeds. Surrounded 

 at the base by persistent calyx and terminated by persistent linear style. 



WOOD Diffuse-porous; hard, strong, brittle, light brown with lighter sapwood. "Weighs 

 39.28 Ibs. per cubic foot. Of little commercial use but occasionally toanufactured into tool 

 handles and engraving blocks. Excellent for fuel where it reaches a fair size. 



DISTINGUISHING CHARACTERISTICS The Great Laurel, also known as Rhododendron 

 and Rose Bay, can be distinguished from all other species of trees native to Pennsylvania by its 

 large, persistent, leathery, simple leaves which are clustered towards the end of the branches 

 and alternate ir their arrangement. Its shrubby form and its preference for moist habitats 

 also aid in distinguishing it. The conical flower-buds, which are usually terminal and often 

 over an inch long, are also characteristic. The twigs are evidently marked by the bud-scale 

 scars. ' 



RANGE Nova Scotia and. Lake Erie on the north, south along the mountains to northern 

 Georgia. 



DISTRIBUTION IN PENNSYLVANIA Found throughout the State. Rare in the southeastern 

 part. Abundant throughout the mountainous parts. 



HABITAT In the North frequents a cold swampy situation. In the South it ascends the 

 mountains to 3,000 feet but remains along the banks of streams. Tolerates most soils except 

 limestone. 



IMPORTANCE OF THE SPECIES The "Rhododendron does not reach a large enough size 

 in Pennsylvania to produce wood of commercial importance. In the South it often becomes a 

 tree. It is the most attractive shrub in our flora, and will thrive in a variety of situations 

 but prefers moist locations and flees from soils which contain lime. 



