46 MISC. PUBLICATION 303, U. S. DEPT. OF AGRICULTURE 
Stomach records: Three species of birds, including ptarmigan and sharp- 
tailed grouse; muskrat. Observations: Redpoll; cottontail rabbit; ignored by 
deer in Massachusetts; summer but not winter food of moose on Isle Royale; 
casually browsed by northern white-tailed deer. 
Alnus maritima (Marsh.) Muhl. Seaside alder. 
Range: 25, 28. 
Site: Well-drained, moist, sun. 
Fruit: Nutlet, borne in a cone, available October-November. 
A large shrub to small or large tree; sometimes forms thickets. 
Alnus mollis, see Alnus crispa. 
Alnus oblongifolia Torr. Mexican alder. 
Range: 11, 14. 
Site: Well-drained, sun. 
Fruit: Nutlet, borne in a cone. 
A small to large tree; usually occurs at higher elevations. 
Alnus occidentalis, see Alnus tenuifolia. 
Alnus oregona, see Alnus rubra. 
Alnus rhombifolia Nutt. White alder. 
Range: 1, 3, 4, 5, 6, 7, 8, 10, 12. 
Site: Moist, shade. 
Fruit: Nutlet, borne in a cone that remains until spring. 
A large tree, often thicket forming; wood rots quickly in soil and is of very 
little value commercially. 
Observations: Of slight importance as food for mule deer. 
Alnus rotundifolia, see Alnus glutinosa. 
Alnus rubra Bong. Red alder, 
A. oregona Nutt. 
Range: 1, 2, 5, 6. 
Site: Well-drained, moist, sun, shade. 
Fruit: Nutlet, borne in a cone; seeds shed in autumn, cones persistent. 
A large tree; rapid growing, especially the first 10 to 15 years; short-lived; 
root system shallow, superficial; wood of increasing value commercially ; 363,000 
seeds per pound, germination 40 percent; about 10,000 usabie plants per pound 
of seed. 
Stomach records; Four species of birds; California mule deer. Observations: 
Pine siskin. Fair browse for cattle and sheep. 
Alnus rugosa (Du Roi) Spreng. Smooth alder. 
A. serrulata Willd. 
Range: (20.22. 23-24 25,26, 26, 28, 29: 
Site: Weill-drained, moist, sun. 
Fruit: Nutlet, borne in a cone. 
A large, thicket-forming shrub with very thick foliage; 400,000 seeds per 
pound, about 40,000 usable plants per pound of seed. 
Observations: Four species of birds, including mourning dove; white-tailed 
deer. 
Alnus serrulata, see Alnus rugosa. 
Alnus sinuata (Regel) Rydb. Sitka alder, 
A. viridis sinuata Regel., A. sitchensis Sarg., A. fruticosa auths. not Rupr. 
Range: 2, 4, 6, 7, 12. 
Site: Moist, sun. 
Fruit: Nutlet, borne in a cone. 
A small to large shrub, or northward a small to large tree. Considered fair 
browse for sheep. 
Alnus sitchensis, see Alnus sinuata. 
Alnus tenuifolia Nutt. Mountain alder. 
A. occidentalis Dippel. 
Range: 4, 7, 11, 12, 138, 14. 
Site: Well-drained, moist, sun. 
Fruit: Nutlet, borne in a cone. 
