188 MISC. PUBLICATION 303, U. S. DEPT. OF AGRICULTURE 
resistant to fire; susceptible to bark beetle damage as well as rot; difficult to 
transplant; a timber tree of the first importance, the principal source of rosin 
and turpentine in the United States. 
Stomach records: Seven species of birds, including bobwhite. Observations: 
Crossbill; much eaten by Carolina fox squirrel and other squirrels. 
Pinus baifouriana Murr. Foxtail pine. 
Range: 4. 
Site: Dry, well-drained, sun. 
Fruit: Cone; mature in August of the second season, seeds shed in 
September, cones soon falling. 
A small to large evergreen tree; five-needled; endures extreme drought in 
its native habitat; intolerant of Shade; wood soft, of little importance commer- 
cially ; susceptible to blister rust. 
Observations: Porcupine; much eaten by birds and rodents; of slight impor- 
tance as browse for mule deer. 
Pinus banksiana Lam. Jack pine. 
P. divaricata (Ait.) Du Mont. 
Range: 23, 24, 26, 27. 
Site: Dry, well-drained, moist (rare), sun. 
Fruit: Cone; mature in September of the second season, seeds shed 
irregularly over several years; cones persistent 12 to 25 years. 
A large evergreen tree; two-needled; often occurs in sandy or rocky soil; at 
first rapid growing, later slower; intolerant of shade; except for the attacks 
of Peridermium cerebrum, generally free from most conifer diseases; has been 
successfully established in the sand-hill section of western Nebraska; wood de- 
cays rapidly in the soil, much used commercially; 105,000-164,000 seeds per 
pound, germination 54 percent. 
Stomach records: One species of bird. Observations: Porcupine. 
Pinus brachyptera Engel. Rocky mountain yellow pine. 
P. ponderosa scopulorum Engelm., P. scopulorum (Engelm.) Lemmon. 
Range: 9, 11, 12, 13, 14, 15. 
Site: Dry, well-drained, sun, 
Fruit: Cone; mature in August of the second season, seeds shed in 
September, cones soon falling. 
A very large evergreen tree; three-needled; forms a long taproot in seedling 
stages but laterals form later; grows on almost any kind of soil; rapid growing 
especially in juvenile stages; very intolerant of shade; resistant to fire; suscep- 
tible to red rot in pure stands and much attacked by insects; wood not durable 
in the soil, of great importance commercially; 10,000-20,000 seeds per pound, 
germination 37-61 percent, about 5,000 usable plants per pound of seed. 
Stomach records: Richardson’s grouse, mountain sheep, plains white-tailed 
deer, black-tailed deer. Cbservations: Five species of birds; white-tailed squir- 
rel, Richardscn’s pine squirrel, Abert’s squirrel, tassel-eared squirrel, spruce 
squirrel, Say’s ground squirrel, chestnut-mantled ground squirrel. Records of 
utilization of P. ponderosa Douglas may apply partially to this species. 
Pinus caribaea Morel. Slash pine. 
P, heterephylla (HU.) Sudw. 
Range: 30, 31, 32. 
Site: Well-drained, moist, sun. 
Fruit: Cone; mature in October, seeds shed the following spring. 
A large evergreen tree; two- to three-needled ; occurs in sandy and other soils; 
rapid growing; subject to red heart or red rot especially northward; wocd hard, 
strong, tough, durable, of value commercially; susceptible to Woodgate rust; 
15,500 seeds per pound, germination 36-85 percent, 
Pinus cembroides Zucc. Mexican pifion. 
Range: 11, 14, 16, 17. 
Site: Dry, weli-drained, sun. 
Fruit: Cone; ripe in September, seeds shed by COctober, cones scon 
falling. 
A small or rarely large, bushy, evergreen tree; commonly three-needied ; slow 
growing; intolerant of shade; wood used for fuel; only the scales in the middle 
of the cone bear seeds; 1,500 seeds per pound, vitality transient. 
Observations: Thick-billed parrot ; birds and rodents. 
