PINACEAE 35 



3. STROBUS Opiz. 



Trees. Leaves needle-like, 5 together, mostly with 1 fibro-vascular bundle each. 

 Staminate aments with involueral bracts at the base. Ovulate aments narrow, 

 stalked. Cones drooping: scales leathery, with neither dorsal appendage nor spine. 

 Seeds samara-like. 



1. StrobuB Strobus (L.) Small. A tree becoming 52 m. tall, with a relatively 

 smooth bark and approxiniately whorled branches: leaves 5 together, 5-10 cm. 

 long, glaucous, very slender; sheaths deciduous or fugaceous: cones narrow, slightly 

 tapering when open, 10-20 cm. long, often curved; scales loosely spreading: seeds 

 6-7 mm. long, the wings usually 2.5 cm. long. 



In sandy or rocky soil, Newfoundland to Manitoba, New Jersey and Iowa, and in the 

 mountains to Georgia and Alabama. Spring. White Pine. 



4. PICE A Link. 



Trees. Leaves solitary, ascending or erect, narrow, angled or terete, leaving 



sterigmata when falling. Pollen-sacs opening lengthwise. Ovulate aments with 



inconspicuous bracts. Cones drooping. Spring. 



Twigs stout, copiously pubescent: leaves over 1 mm. broad, blunt or mucronate: cones persistent. 



1. P. Mariana. 

 Twigs slender, glabrate or merely pubescent between the decurrent sterigmata: 



leaves barely 1 mm. broad, acute: cones early deciduous. 2. P. ausiralis. 



1. Picea Mariana (Mill.) B.S.P. A tree becoming 30 m. tall, the bark rough: 



twigs stout stiff, pubescent as are usually the sterigmata: leaves curved, 8-12 mm, 



long, deep green: cones oval or ovoid, 2.5-4 cm. long. 



In moist soil, Newfoundland to Saskatchewan and New Jersey, and in the mountains to 

 North Carolina. Black Speuce. He Balsam. Tamarack, Yew Pine. Lash-horn. 



2. Picea austr^lis Small. A tree becoming 40 m. tall, the bark relatively 

 smooth: twigs slender, glabrous or merely pubescent in lines between the decurrent 

 glabrous sterigmata: leaves slender, 8-14 mm. long, straight or nearly so, bright 

 green: cones oblong, oval or ovoid, mostly less than 2.5 cm. long. 



On dry mountain slopes or summits, Virginia and North Carolina. 



5. TSUGA Carr. 



Trees. Leaves distichously spreading: blades linear, glaucous beneath, not 

 jointed to sterigmata. Pollen-sacs opening transversely. Ovulate aments with incon- 

 spicuous bracts. Cones drooping. Spring. Hemlock. 



Twigs tomentose with long hairs: cones narrowly ovoid when closed, 1.8-2.3 cm. long: scales nearly 

 erect. 1. T. Canadensis. 



Twigs tomentose with short hairs, or glabrate: cones cylindric-oblong when 



closed, 3 cm. long: scales spreading at right angles. 2. T. Caroliniana. 



1. Tsuga Canadensis (L.) Carr. A tree becoming 31 m. tall, with a scaly- 

 exfoliating bark: leaves loosely spreading, 6-14 mm. long, obtuse at the apex: stam- 

 inate aments 2 mm. in diameter: cones oblong when open, 18-23 mm. long; scales 

 erect, suborbicular : seed-wings mainly less than 1 cm. long. 



On rocky banks, in woods and ravines, Nova Scotia, Quebec and Wisconsin, to Delaware, 

 and on the Alleghenies or in their vicinity to Georgia and Alabama. Spruce Pine. 



2. Tsuga Caroliniana Engelm. A tree becoming 25 m. tall, the bark relatively 



smooth: leaves rigidly spreading, mostly notched at the apex: staminate aments 



about 3 mm. in diameter: cones ovoid when open, 25-30 mm. long; scales spreading, 



oblong or nearly so: seed-wing over 1 cm. long. 



In ravines and on rocky moimtain slopes from southwestern Virginia to northeastern 

 Georgia. Crag Hemlock. Carolina Hemlock. 



6. ABIES Mill. 



Trees. Leaves distichously spreading on twigs and branchlets: blades linear, 

 not jointed to sterigmata. Pollen-sacs opening transversely or nearly so. Ovulate 

 aments with conspicuous bracts. Cones erect, cylindric. FiR. 



1. Abies Pr^seri (Pursh) Lindl. A tree becoming 25 m. tall, the bark with 

 balsam-yielding blisters: leaves 1-2 cm. long; blades shining above, glaucous be- 

 neath: staminate aments 5-8 mm. long: cones 4-5 cm. long; scales flabellate; bracts 

 exserted, apiculate: seeds 4-5 mm. long, the wing about as wide as long. 



On mountain peaks, southern Virginia to Tennessee and North Carolina. Spring. 

 Silver Fir. She Balsam. Lash Horn. 



