Important Forest Trees of the United States 



811 



154. Cascara buckthorn. 155. Pacific madrone. 156. Golden chinquapin. 157. Tanoak. 



152. BLACK COTTONWOOO, Populus trichocarpa Torr. & Gray (California poplar, cotton- 

 wood, balsam cottonwood, western balsam poplar; variety: P. trichocarpa var. hastata 

 (Dode) Henry, Pacific poplar). 



Large tree (the tallest western broadleaf tree) of northern Rocky Mountain and Pacific 

 coast regions north to Canada and Alaska. Bark gray, smooth at first, becoming deeply fur- 

 rowed with flat ridges. Leaves broadly oval, 3 to 7 inches long, short- or long-pointed, finely 

 toothed, smooth or slightly hairy, dark shiny green above, whitish or rusty beneath. Leaf- 

 stalks round. 



Principal uses: Boxes and crates, pulpwood, and excelsior. 



XX. Leafstalks less than 1 inch long, leaves elliptical or oval ; seeds not hairy. 

 Y. Leaf edges with teeth of 2 sizes and slightly irregular ALDER 

 (Alnus; see also No. 84). 



153. RED ALDER, Alnus rubra Bong, (alder, Oregon alder, western alder). 

 Medium-sized to large tree of Pacific coast region north to Canada and Alaska. Bark 



mottled light gray to whitish, smooth, thin. Leaves oval or elliptical, 3 to 6 inches long, 

 short-pointed, both coarsely and finely toothed, dark green and nearly smooth above, 

 grayish green or rusty beneath. Cones l /2 to 1 inch long. 



Principal uses: The leading hardwood in the Pacific Northwest. Furniture. 



YY. Leaf edges with uniform, small teeth BUCKTHORN (Rhamnus; 

 see also Nos. 76 and 87). 



154. CASCARA BUCKTHORN, Rhamnus purshiana DC. (cascara sagrada, cascara). 

 Small tree or shrub of northwest Pacific coast and northern Rocky Mountain regions 



north to British Columbia. Bark brown or gray, thin, scaly. Leaves elliptical, 2 to 6 inches 

 long, blunt-pointed or rounded, finely toothed, dark green above, lighter and slightly hairy 

 beneath. Fruits berrylike, $/Q to l /2 inch in diameter, purplish black, with 2 or 3 seeds. 



Principal uses: The bark is the source of the drug Cascara Sagrada. Wood is used 

 locally for fuel and fence posts. Ornamental. 



WW. Leaves thick, with edges mostly smooth, evergreen. 

 Z. Leaves pale or whitish beneath MADRONE (Arbutus}. 



155. PACIFIC MADRONE, Arbutus menziesii Pursh (madrono, madrona). 



Small to large tree of Pacific coast region north to British Columbia. Bark of limbs and 



