The Pines 



Leaves flat. 

 Leaves not jointed to woody stalks. 



Cones pendulous, their scales persistent after maturing. 

 Cones erect, their scales falling away from the axis. 

 Scales of the cone few; leaf-buds naked (except in Taxodiuni, a species 

 of Sequoia and some species of Juniperus). 

 Cone-scales spiral, thick. 

 Leaves persistent; cones oblong. 

 Leaves deciduous; cones globose. 

 Cone-scales opposite. 



Cones ovoid to oblong, their scales thin. 

 Cone-scales 6; seed unequally winged. 

 Cone-scales 8 to 12; seed equally winged. 

 Cones globose, their scales thick. 

 Cones large, maturing the second year; seed narrowly winged; 



twigs quadrangular. 

 Cones small, maturing the first year; seed broadly winged; 

 twigs flattened. 

 Fruit fleshy, a modified cone, berry-like. 



4. Tsuga. 



5. Pseudotsiiga. 



6. Abies. 



7. Sequoia. 



8. Taxodiuni. 



9. Heyderia. 

 10. Thuja. 



11. Cupressus. 



12. ChamcEcyparis. 



13. Juniperus. 



I. THE PINES 



GENUS PINUS [TOURNEFORT] LINN^US 



HIS genus consists of evergreen trees, a few of which are reduced to 

 shrubs at high altitudes or high latitudes. They are apparently con- 

 fined to the northern hemisphere and represented by nearly 100 species, 

 of which fully one third are natives of North America. 

 They are of great economical importance. The wood of some species, espe- 

 cially that of the white pines, is valued on account of its evenness, softness, and the 

 ease with which it can be worked ; the harder, resinous woods of the pitch pines 

 or yellow pines are also used to a very large extent and are more durable in con- 

 tact with the ground. The resinous juice is of great importance in the arts, being 

 the source of the so-called oil or spirits of turpentine which is secured from the 

 juice by distillation, the residue constituting commercial resin. Tar is produced 

 by a more or less crude process of destructive distillation of pine wood, the residue 

 being charcoal. Tar when subjected to distillation yields oil of tar and a thick 

 residue called naval pitch; all these products are used to a greater or less extent 

 in medicine; volatile oils are also obtained from various species of pine leaves, 

 young shoots or young cones, and have some specific appHcation in medicine. 

 The fiber from some of the long leaves of pines is sometimes extracted for special 

 apphcations. The large seeds, especially notable in the group called nut pines, 

 are very nutritious and are an important article of food, especially to the Indians 

 of the southwestern United States and Mexico; also in southern Europe where 

 the seed of the stone pine is of much importance. As ornamental trees the pines 

 are too well known to require more than mention here. 



