PINACEAE 



Jack Pine 



Pinus banksiana Lamb. 



HABIT. A tree rarely 60-80 feet high (max. 90 by 2 feet); 

 bole often crooked; crown open, irregular, scraggly. 



LEAVES. In fascicles of 2; Ya-^Yi inches long; divergent; 

 stout; twisted; yellow-green; persistent 2-3 years; margins 

 with minute teeth; basal sheath persistent. 



FLOWERS. Male yellow; female dark purple; clustered. 



FRUIT. Sessile; lVi~2 inches long; oblong-conic; unsym- 

 metrical; often remaining closed and on tree for years; scales 

 irregularly developed, unarmed or with minute, deciduous 

 prickle. Seeds: 3^2 inch long, black; wing about V^ inch long. 



TWIGS. Thin, tough, flexible; becoming rough and red- 

 brown. Winter buds: H inch long, ovoid, pale cinnamon- 

 brown. 



BARK. Thin; dark red-brown; shallowly ridged. 



WOOD. Moderately important; light and soft; heartwood 

 light-brown; used for pulp, fuel, posts, etc. 



SILVICAL CHARACTERS. Very intolerant; short-lived; 

 wide-spreading roots with a taproot; reproduction vigorous. 



HABITAT. Essentially Canadian, extending farther north 

 than other pines; dry, sterile soils; mostly in pure stands. 



Virginia Pine 



Pinus virginiana Mill. 



This species is similar to jack pine in habit, twigs, bark, wood, 

 silvical characters, and site; it differs from jack pine in distribu- 

 tion and the following characters: 



LEAVES. In fascicles of 2; lJ^-3 inches long; divergent; 

 stout; twisted; gray-green; persistent 3-4 years; margins with 

 minute teeth; short-needled trees hardly distinguishable from 

 jack pine. 



FLOWERS. Male orange-brown; female pale green tinged 

 with rose. 



FRUIT. Subsessile; lVi-3 inches long; ovoid-conic; sym- 

 metrical; opening at maturity but persisting on twigs 3-4 years; 

 scales thin, flat, with persistent prickle and deep purple inner 

 lip. Seed: 14 inch long, pale brown, with wing about 1 inch 

 long. 



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