52 PIN ACE AE 



Family 2. PINACEAE. 



Pine Family. 



Resinous evergreen or rarely deciduous trees or shrubs, with linear, needle-like 

 or scale-like leaves, arranged in spirals. Flowers surrounded at base by the per- 

 sistent bud scales, monoecious, the staminate consisting of many spirally arranged 

 stamens, with 2 pollen-sacs, the ovulate of many scales, bearing 2 pendent ovules 

 on their inner surface. Fruit a woody cone, maturing the first or second season. 

 Seeds with or without wings ; embryo axile in the copious endosperm ; cotyledons 

 several. 



A family of 8 genera and approximately 150 species widely distributed over the northern hemisphere. 



Cones maturing the second or third year; leaves surrounded at base by a persistent or deciduous sheath, in 



bundles of 2-5 (solitary in one species). 1. Piiius. 



Cones maturing the first year; leaves not in sheaths, solitary, often appearing 2-ranked. 



Leaves deciduous, forming tuft-like clusters on short spur-like branchlets. 2. Larix. 



Leaves persistent, scattered along ordinary branchlets. 

 Cones pendulous, their scales persistent. 



Bracts concealed by the scales; branchlets roughened by the woody persistent leaf bases. 



Leaves sessile on the woody stalk4ike bases, 4-sided or flattened and stomatiferous above. 



3. Picea. 

 Leaves narrowed to a short petiole, flattened and stomatiferous below or angular. 



4. Tsuga. 



Bracts exserted beyond the cone-scales, with 3 prominent awns; leaves without woody bases, leaving 

 the branchlets smooth, narrowed to a short petiole. 5. Pseudotsuga. 



Cones erect, their scales deciduous; leaves sessile, leaving the branches smooth. 6. Abies. 



1. p'iNUS [Tuurn.] L. Sp. PI. 1000. 1753. 



Evergreen trees or rarely shrubs, with furrowed or thin, scaly bark, rather hard or 

 often soft wood. Ltaves of two kinds, the secondary forming the ordinary foliage leaves, 

 needle-like, borne in clusters of 2-5, or solitary in one species, terminating short rudi- 

 mentary branchlets in the axils of the scale-like primary leaves, surrounded at base by a 

 deciduous or persistent membranous sheath, persistent from 2-8 years. Staminate flowers 

 clustered at the base of the season's growth, forming a distinct zone on the twig which 

 becomes naked after the flowers have fallen, each flower subtended by an involucre of 

 several scales, composed of many 2-celled anthers ; ovulate flowers subterminal, or lateral, 

 solitary, in pairs or clustered, sessile or stalked, consisting of many ovule-bearing scales, 

 subtended by non-accrescent bracts, and bearing 2 pendent ovules. Fruit a cone, maturing 

 the second year, or sometimes the third year, opening and shedding the seeds at maturity, 

 or, in some species, remaining closed and persistent on the branches for years ; cone-scales 

 elongated, variously thickened and appendaged at the exposed apex (apophysis). Seeds 

 often with conspicuous membranous wings, their coats crustaceous; cotyledons 3-15, or 

 sometimes more. [The classical Latin name.] 



A genus of about 100 species widely scattered over the northern hemisphere. Type species, Finns 

 sylvestris L. 



Sheaths of the leaves deciduous; leaves with one fibyo-vascnlar hiindlc; wood soft, light-colored, close- 

 grained, li'ith thin nearly white sapwood. 

 Leaves in 5-leaved clusters. 



Cones with terminal unarmed umbos. 



Seeds much shorter than the wings; cones long-stalked, their scales thin. 



Leaves obtuse at apex; cones 12-25 cm. long; seed-wings acute. L P. vionticola. 



Leaves sharp-pointed; cones 30-45 cm. long; seed-wings rounded at apex. 2. P. lambertiana. 

 Seeds much longer than the short wings; cones short-stalked, their scales thick, sometimes with 

 pointed umbos. 

 Cones opening at maturity, 8-20 cm. long. 3. P. flexilis. 



Cones remaining closed, 2-7 cm. long. 4. P. albicauhs. 



Cones with dorsal umbos armed with slender prickles; seeds shorter than the wings. 



Cones armed with minute incurved prickles. 5. P. ialfouriana. 



Cones armed with long slender prickles. 6. P. aristata. 



Leaves in 1-4-leaved clusters; cones subglobose, their scales few, much thickened, only the middle seed- 

 bearing; seeds large, wings a mere ring. 

 Leaves usually in 4-leaved clusters. 7. P. quadrifoUa. 



Leaves usually in 1 -leaved clusters. 8. F. monophylla. 



Sheaths of the leaves persistent ; leaves with two fibro-vasctilar bundles: xvood usually heavy, rather hard, 

 coarse-grained, generally dark-colored, with often thick pale sapwood. 

 Leaves in 5-leaved clusters. 9. P. torreyana. 



Leaves in 2-leaved or 3-leaved clusters. 



Leaves in 3-leaved clusters, or sometimes only 2 in a cluster in P. radiata and P. ponderosa. 

 Cone-scales with dorsal slender prickles. 



Cones symmetrical, opening at maturity, deciduous, the basal scales persistent on the branches. 

 Leaves yellow-green; branchlets not glaucous; cones 7-15 cm. long. 10. P. ponderosa. 



Leaves dull bluish green; branchlets glaucous; cones 15-35 cm. long. 11. P. jeffreyi. 



