BROADLEAVED TREES OF YOSEMITE NATIONAL PARK 



23 



BIGLEAF MAPLE 

 Acer macrophyllum Pursh — Maple Family (Aceraceae) 



This common tree can be readily 

 recognized by even the most casual 

 observer by its large, characteristic 

 leaves. Although it may be found as 

 high as 5,500 feet in elevation in 

 Yosemite National Park, it is most 

 common between 3,000 and 4,500 

 feet where it grows in moist, gravelly 

 soils upon hillsides, in protected lo- 

 cations at the base of cliffs, or in the 

 rich alluvial soils bordering streams. 

 Its natural range includes an area 

 along the Pacific Coast from south- 

 eastern Alaska to southern Califor- 

 nia. 



Although it is not exceptionally 

 large as a rule, it is a handsome tree. 

 Mature specimens may attain a 

 maximum of 80 feet in height ana 



two to two and one-half feet in di- 

 ameter. When growing in the open 

 the large, heavy branches produce 

 a broad, spreading, round-topped 

 crown densely covered with foliage. 

 In less favorable situations it is char- 

 acterized by a more ragged, less 

 pleasing appearance. New twigs are 

 smooth and green, while larger bran- 

 ches have a pale grey or reddish- 

 brown color. Gray to reddish-brown 

 bark with hard, scaly ridges charac- 

 terize the trunks of larger trees. Al- 

 though it grows rapidly at first its rate 

 of growth decreases with age. It 

 reaches maturity in about 200 to 300 

 years. 



The foliage is unmistakable. Borne 

 on stems four to six inches long, the 



Photo by Brockman 



foliage and iccils of biglcaf maple {Inch squares on background) 



