Bailey & Bailey: Woody Plants of National Parks 



57 



Mammoth and Norris Junction. GRAND TETON, occasional: head of Death Canyon; 

 North Fork Cascade Canyon, 8,000 feet. ROCKY MOUNTAIN, common, 8,000 to 11,000 

 feet; southwest of Mount Bryant; Moraine Park. 



3. Low Birch (Betula pumila L. var. 

 glandulijera Regel.). — Spreading shrub 11/2 to 

 9 feet high with somewhat resinous or gland- 

 dotted twigs and fohage; leaves thiclcish, re- 

 verse-egg-shaped to round or kidney-shaped, ^/^ 

 to II/4 inches long; fruiting catkins ^ to II/4 

 inches long. 



Occurrence. — isle royale, rare: bog on Rasp- 

 berry Island. 



Alder (Alnus Hill) 



The shrub species of alder found in our 

 national parks, like the tree species, are com- 

 mon along streams or in moist meadows. They 

 are important along stream banks as protec- 

 tion against erosion. The plants spread by 

 suckers and underground stems and frequently 

 form extensive thickets so dense that they are 

 practically impenetrable. During the winter 

 in regions of heavy snow the stems may be 

 bent to the ground. Beaver cut the stems of 

 alders for building their dams and houses and 

 strip the bark from the branches for food. The 

 twigs furnish important winter forage for deer 

 and elk. The Blackfeet Indians used the 

 tough bark covered with rawhide for making 



stirrups. 1- Nitrogen-fixing bacteria form nodules on the roots of alders in 

 somewhat the same manner as on the roots of members of the pea family. 



Fig. 12. Bog birch {Belula 

 glandiilosa). 



Field Guide to the Species 



Leaves rather coarsely double-toothed; flowers developing before the leaves; cones 

 borne on short sfoutish stalks; nutlets not wmged or very narrowly winged. 



Western species 1. A. lenuifolia. 



Eastern species 2. A. incana. 



Leaves finely and sharply toothed; flowers developing with the leaves; cones borne 

 on slender stalks usually as long as the cones or longer; nutlets with con- 

 spicuous thin wings. 



Western species 3. A. sinuala. 



Eastern species 4. A. crispa. 



12 Standley, P. C, Flora of Glacier National Park. Contributions from the United 

 States National Herbarium, vol. 23: 5. 1921. 



