23. Needles in 2's and 3*8, or 3's. 



25. Cones massive, 6-14' long, clawlike spines; needles in 3*s. 

 26. Cones yellow-brown, 10-14" long; seeds shorter than 



wings; southern and lower California 



P. coulteri, Coulter Pine, p. 37. 



26. Cones red-brown, 6-10" long; seeds longer than wings; 



dry California foothills ' 



P. sabiniana. Digger Pine, p. -37. 



25. Cones not massive; without clawlike spines. 



27. Cones unsymmetrical with thickened scales, often 

 remaining closed and persistent for years. 



28. Needles in 2's, 1-3" long; cone under 2" long. 



29. Cones with knoblike scales and long prickles. 

 30. Needles 1-1 3^" long; small contorted tree 



of coastal area 



P- coniorta. Shore Pine, p. 35. 



30. Needles 1-3" long; straight, slender. 



mountain tree throughout West P. 



contorta latifolia, Lodgepole Pine, p. 35. 

 29. Cones with thin scales and minute prickle; 



Canada and Northeastern United States 



P- banksiana. Jack Pine, p. 19. 



28. Needles 3-7" long; cones 2-6" long; Oregon and 

 California. 

 31. Needles in 2's; cones 2-3 H" long, with stout, 



spurlike prickles 



P- muricata. Bishop Pine, p. 41. 



31. Needles in 3's; cones 3-7" long, without spur- 

 like prickles. 



32. Thickened cone scales, flattened, pyram- 

 idal; dry foothills; California and Oregon 

 .... P. attenuata, Knobcone Pine, p. 39. 

 32. Thickened cone scales, rounded, dome- 

 like ; California coast 



P- radiata, Monterey Pine, p. 39. 



27. Cones symmetrical, thin-scaled. 



33. Needles in 3's, 2-4" long, cluster sheath deciduous; 

 cone 13^-2" long, maturing in 3 years, long- 

 stalked, often remaining closed, long persistent, 



southern Arizona and southern New Mexico 



P- leiophylla. Chihuahua Pine, p. 35. 



33. Needles over 4" long, sheath persistent; cone 2-15" 

 long, maturing in 2 years, short-stalked, opening, 

 deciduous, the basal scales remaining on twig. 

 34. Cones 2-3 3^" long; needles 4-6" long; rare 



and local in Washoe County, Nevada 



P. washoensis M. & S.. Washoe Pine, p. 33. 

 34. Cones 3-15" long; needles 4-15" long. 



35. Cones 5-15" long; needles 4-9" long, 

 persistent 6-9 years; twigs purplish with 

 lemon-like odor; buds not covered with 

 resin droplets; California and Oregon. . . . 



P- jeffreyi, Jeffrey Pine, p. 33. 



35. Cones 3-6" long; needles persistent 2-3 

 years ; twigs orange to red with tiu-pentine 

 odor; buds often covered with resin 

 droplets. 



36. Needles 4-11" (mostly 5-7") long, in 

 2's and 3's, yellow-green; throughout 



west 



P. ponderosa, Ponderosa Pine, p. 31. 



36. Needles 8-15" long, in 3's (rarely 2-5), 



da7:k green; Arizona and New Mexico 



P. engelmannii, Apache Pine, p. 33. 



[5] 



