18 PINACEAE 



Bracts much shorter than the cone-scales; leaves blue-green and glaucous. 



Bark of the trunk hard, not corky; cone-scales longer than broad. 2. A. lasiocarpa. 



Bark of the trunk elastic, corky; cone-scales broader than long. 3. A. arizonica. 

 Resin-ducts of the leaves close to the epidermis on the lower side. 



Bracts obcordate with a short acumination ; leaves (except those of the cone-bearing 



branches) emarginate, dark green above, white beneath. 4. A. grandis. 



Bracts truncate with a short acumination; leaves acute or acuminate, seldom obtuse 



at the apex, pale blue-green and glaucous 5. A. concolor. 



7. PSEUDOTSUGA Carr. Red Fir, False Spruce. i. P. mucwnaia. 



8. TSUGA (Endl.) Carr. Hemlock. i. T. heierophylla. 



9. HESPEROPEUCE Lemmon. Black Hemlock, Mountain Hemlock. 



10. PICEA Link. Spruces. l. H. Merlensiana . 



Cone-scales rounded at the apex. 



Branchlets pubescent; cones 1.5-3 cm. long, persistent for several years; scales rigid, 



erose or dentate. 1. P. Mariana. 



Branchlets glabrous; cones 3-5 cm. long, deciduous in the first winter; scales rather 

 tliln. 

 Cone-scales entire or minutely denticulate on the margins; cones cylindric- 



oblong, 3.5-5 cm. long. 2. P. canadensis. 



Cone-scales erose on the margins; cones ellipsoid, 3-3.5 cm. long. 3. P. albertiana. 

 Cone-scales more or less rhomboid in outline. 



Branchlets pubescent; cones 3-5 cm. long. 4. P. Engelmanni. 



Branchlets glabrous; cones 5-9 cm. long. 5. P. pungens. 



Family 2. JUNIPERACEAE. Juniper Family. 



Plants monoecious; cones dry; scales merely imbricate. I. Thuja. 



Plants mostly dioecious; cones berry-like or drupe-like, with coalescent fleshj scales. 

 Ameuts axillary; cones with smaller scales at the top; leaves all subulate and 

 spreading. 2. Juniperus. 



Aments terminal ; pistillate cones with larger scales at the top ; leaves at least of the 

 mature plants scale-like and appressed. 3. Sabina. 



1. THUJA L. Arbor Vitae, White Cedar. i. t. plicata. 



2. JUNIPERUS (Tourn.) L. Juniper. 



Low shrub with depressed branches; leaves abruptly bent at the base, deeply channeled, 

 abruptly acute. 1. J- sibirica. 



Tree or erect shrub; leaves straight or nearly so, shallowly channeled, gradually 

 acuminate. 2. d. communis . 



3. SABINA Haller. Red Cedar. 



Fruit reddish-brown or bluish by a bloom, with dry fibrous sweet flesh. 



1. S. utahensis. 

 Fruit blue or blue-black, rarely copper-colored, with juicy resinous flesh. 



Trees or erect shrubs; fruit on straight peduncles. 

 • Leaves minutely dentate at the apex; fruit 5-8 mm. in diameter. 



Leaves not glandular or obscurely so; seeds usually 1. 2. S. monosperma. 



Leaves very glandular; seeds 2 or 3. 3. S. occidcntalis. 



Leaves entire; fruit 4-5 mm. in diameter, usually with more than one seed. 



4. S. scopnlorum. 

 Prostrate shrub; fruit on recurved peduncles. 5. S. horizontalis. 



Family 3. TAXACEAE. Yew Family. 

 1. TAXUS (Tourn.) L. Yew. I. T. brer i folia. 



Family 4. EPHEDRACEAE. Joint Fir Family. 



1. EPHEDRA L. Joint Fir, Brigham Tea. 



Scales and branches opposite; bracts opposite and coimate, only the margins scarious. 

 Scales distinct, subpertensist; filaments free above. 1. E. antisyphylitica. 



Scales connate, sheatliing, scarious, deciduous; filaments adnate to the top of the 

 bracts. 

 Branches stout, more or less spreading; plant Ught brownish green. 



2. E. nevadensis. 

 Branches slender, erect; plant bright yellowish green. 3. E. viridis. 



Scales, branches, and bracts in 3's; bracts scarcely connate, those of the pistillate 

 aments nearly wholly scarious and more or less imgiiiculate. 

 Scales 2-3 mm. long, not becoming shreddy; fruit scabrous. 4. E. Torreyana. 



Scales 6-12 mm. long, becoming slu-eddy; fruit smooth. 5. E. trifurca. 



