NATIVE WOODY PLANTS OF THE UNITED STATES 



lived ; easily damaged by fire when young, less so with age ; much attacked 

 by fungi ; easily storm damaged ; fairly wind-firm ; 1,300,000 seeds per pound, 

 germination 60-90 percent, vitality transient; stump sprouts and root sprouts 

 produced ; has been successfully used in checking erosion and in fixation of sand 

 dunes; wood used commercially; grows on coal-stripped lands in Illinois. 



Stomach records: Black-tailed deer. Observations: Evening, and rose-breasted 

 grosbeak ; cottontail rabbit. Much browsed by cattle. 



Populus fremontii Wats. Fremont cottonwood. 



P. macdougalii Rose. 



Range : 1, 3, 4, 5, 9, 10, 11, 13, 14. 

 Site : Well-drained, moist, sun. 

 Fruit: Capsule. 



A large tree ; commonly occurs in sandy soil ; grows well in saline soils ; 

 rapid growing, short-lived ; wood used locally ; much attacked by mistletoe. 

 Several varieties are described, all occurring within the range of the species. 

 Observations: California mule deer. 



Populus grandidentata Michx. Largetooth aspen. 



Range : 21, 22, 23, 25, 26, 27, 28. 

 Site : Dry, well-drained, moist, sun. 

 Fruit : Capsule, available in May. 



A small to large tree ; grows in sand, humus or loam ; root system shallow ; 

 very rapid growing, short-lived ; often severely injured by fungi, fire, wind, and 

 insects ; wood iised commercially ; a pioneer in burned and cut-over land ; germi- 

 nation percentage of seeds high, vitality transient. 

 Observations: Cottontail rabbit, white-tailed deer. 



Populus heterophylla L. Swamp cottonwood. 



Range: 25, 27, 28, 29, 30. 



Site : Moist, sun. 



Fruit : Capsule, available in May. 



A large tree ; root system very shallow ; rapid growing, short-lived ; subject 

 to heart rot at maturity ; wood of importance commercially. 



Populus macdougalii, see Populus fremontii. 

 Populus mexicana, see Populus arizonica. 

 Populus occidentalis, see Populus sargentii. 



Populus palmeri Sarg. Palmer cottonwood. 



Range: 16, 20. 



Site : Well-drained, moist, sun. 

 Fruit: Capsule. 

 A large tree. 



Populus sargentii Dode. Sargent cottonwood. 



P. deltoidcs occidentalis Rydb., P. occidentalis (Rydb.) Britt., P. angulata 

 Port, and Coult. 



Range : 12, 13, 14, 15, 16, 18, 19, 21. 

 Site : Well-drained, moist, sun. 

 Fruit: Capsule. 

 A large tree ; rapid growing, short-lived ; wood used to some extent locally. 



Populus tacamahaca, see Populus balsamifera. 



Populus texana Sarg. Texas cottonwood. 



Range: 16. 



Site : Well-drained, moist, sun. 

 Fruit: Capsule. 

 A large, short-lived, rapid-growing tree. 



Populus tremuloides Michx. (pi. 24, A, B,}. Quaking aspen. 



P. aurea Tidest., P. vancouveriana Trel., P. cercidiphylla Britt. 



Range : 1, 2, 4, 6, 7, 8, 9, 11, 12, 13, 14, 15, 18, 21, 22, 23, 24, 25, 26, 27. 

 Site: Dry, well-drained, sun. 

 Fruit : Capsule, available May-June. 



A small to large tree ; occiirs in many soils ; apparently not satisfactory in 

 pure plantations owing to insects and disease ; root system shallow ; will grow in 

 many soils but apparently does best in sandy loam ; very rapid growing, short- 

 lived ; easily and seriously damaged by fire, wind, fungi, and insects ; wood 



