PINACEAfi 

 Jack Pine. Scrub Pine 



Pinus banksiana, Lamb. [Pinus divaricata, (.Ait.} 

 Du Mont de Cours.] 



HABIT. Usually a small tree 20-30 feet 'high, with a trunk 

 diameter of 8-12 inches ; forming a crown varying from open and 

 symmetrical to scrubby, stunted, and variously distorted. 



LEAVES. In clusters of two; about I inch long; narrow- 

 linear, with sharp-pointed apex; stout, curved or twisted, diver- 

 gent from a short sheath ; dark gray-green. Persistent 2-3 years. 



FLOWERS. May-June; monoecious; the staminate in ob- 

 long clusters l /2 inch long, composed of many sessile, yellow 

 anthers imbricated upon a central axis; the pistillate in sub- 

 globose clusters, composed of many carpel-like, purple scales 

 (subtended by small bracts) spirally arranged upon a central axis. 



FRUIT. Autumn o'f second or third season, but remaining 

 closed for several years and persistent on the tree for 10-15 years ; 

 erect, usually incurved, oblong-conical, sessile cones, i l /2-2 

 inches long; scales thickened at the apex; seeds triangular, nearly 

 black, y% inch long, with wings Yz inch long. 



WINTER-BUDS. Terminal bud Y 4 inch long, ovoid, 

 rounded, pale brown ; lateral buds smaller. 



BARK. Twigs yellow-green, becoming purple, finally dark 

 red-brown and rough with the persistent bases of fallen leaves; 

 thin, dark red j brown on the trunk, with shallow, rounded ridges, 

 rough-scaly on the surface. 



WOOD. Light, soft, weak, close-grained, light brown, with 

 thick, whitish sapwood. 



DISTRIBUTION. Common from Clare County northward ; 

 occurs sparingly along the lake shore as far south as Grand 

 Haven on the west and Port Austin on the east. 



HABITAT. Sandy, sterile soil. 



NOTES. Cones open unevenly. Slow of growth. Difficult 

 to transplant. 



