KEY, BASED UPON LEAVES. 13 



(1. 4-sided ; branchlets 



Pubescent 20. PICEA NIGRA. 



Glabrous 100. PICEA ALBA. 



d?. Flat ; branchlets smooth ; cones cylindrical 149. PICEA SITCHENSIS. 



ft 2 . Linear, flat and 



c. Conspicuously 2-ranked (diverging in two directions), 

 d. Petioled and margin 



Obscurely denticulate, 8 lines or less in length. . . .21. TSUGA CANADENSIS. 



Entire, re volute, -J-l inch in length 144. TAXUS BREVIFOLIA. 



rf 2 . Subsessile rigid and sharply bristle-pointed, about 1 inch long and gene- 

 rally tapering from wide base 120. TORREYA TAXIFOLIA. 



1-3 inches long, of more nearly uniform width 



145. TORREYA CALIPORNICA. 

 d z . Sessile, entire, |-f inches long, keeled below 



Narrow-linear, obtusely pointed 22. ABIES BALSAMEA. 



Wide-linear, pungent at apex 143. SEQUOIA SEMPERVIRENS. 



c 2 . Somewhat 2-ranked, short petiolate 150. PSEUDOTSUGA TAXIFOLIA. 



ft 3 . Scale like or awl-shaped, inbricated and closely appressed 

 c. In 4 ranks and making a conspicuously 



Flat two-edged branchlet 24. THUYA OCCIDENT ALIS , 



Flattish but narrower branchlet 141. LIBOCEDRUS DECURRENS. 



4-angled rather than flat branchlet ; fruit a 



Small spherical cone 74. CHAMJECYPAIS THYOIDES. 



Bluish berry 25. JUNIPERUS VIRGINIANA. 



c 2 . Scattered or spirallay arranged, mostly carminate . . 142. SEQUOIA GIGANTEA. 

 ft 4 . Laminate and ovate to obovate 



c. ^-H in ' long, serrate above, entire at base. .130. CERCOCARPUS PARVIFOLIUS. 

 c 2 . 1-5 in. long, 



d. Rounded or truncate at base, 

 e. Pale glaucous beneath, darker above, 3-5 in long, entire, flat . 



132. ARBUTUS MENZIESII. 

 e 2 . Tomentose and concave beneath, margin 



Serrate-dentate 138. QUERCUS DENSIFLORA. 



Entire and undulate 131. GARRYA ELLIPTICA. 



cZ 2 . Cuneate at base, glabrous or nearly so beneath, flat. 



117. QUERCUS VIRENS. 

 c 3 . 6-12 in. long, thick, entire, acute at both ends. 



101. MAGNOLIA GRANDIFLORA. 

 c 4 . 3-6 in. long, blade articulated to the petiole which is 



Conspicuously winged; stamens usually 20 103. CITRUS AURANTIUM. 



Slightly if at all winged; stamens usually 35 104. CITRUS LIMONUM. 



ft 5 . Lanceolate -oblong. 

 c. 3-5 in. long, margin 



el. Crenate-serrate , . . 102. GORDONIA LASIANTHUS. 



<? 2 . Entire and leaves 



e. Opposite, glabrous beneath 112. OSMANTHUS AMERICANUS. 



e 2 . Alternate and beneath 



Rusty-pubescent 113. PERSEA CAROLINENSIS var. PALUSTBIS. 



Golden-scurfy beneath 139. CASTANOPSIS CHRYSOPHYLLA. 



c 2 . 2 in, long, entire, glandular beneath 108. CLIFTONIA LIGUSTRINA. 



ft 6 . Oblong or elliptical, small, l|-4 in .117. QUERCUS VIRENS. 



* 4 . Leaves Suboersistent Evergreen southward, but more or less deciduous 

 northward, or individual trees shedding their leaves while most of the trees 

 do not. 



Narrow obovate; 1-3 in. long 107. CYRILLA RACEMIFLORA. 



Lanceolate to oval, 3-6 in. long, glaucous beneath. . . .51. MAGNOLIA GLAUCA. 

 Orbicular-oblong, sinuately spinous-toothed 137. QUERCUS AGRIFOLIA. 



