ROSACEAE 



American Plum 

 Prunus americana Marsh. 



HABIT. A shrub or small tree 25-30 feet high and rarely 

 12 inches in diameter; trunk short, usually dividing near the 

 ground; crown broad, with many spreading branches; usually 

 spreading by shoots from the roots into dense thickets. 



LEAVES. Oval to slightly oblong-oval, or sometimes obo- 

 vate; acuminate at apex; sharply and often doubly serrate; 

 thick and firm; dark green above, pale and glabrous below; 

 3-4 inches long and P/i-lH inches wide; petiole slender, Vi-% 

 inch long. 



FLOWERS. In 2-5-flowered umbels; on slender, glabrous 

 pedicels Vi-% inch long; appearing before or with leaves; ill- 

 scented; calyx tube narrow, bright red without, green and 

 pubescent within; corolla white, 1 inch in diameter. 



FRUIT. Subglobose; about 1 inch in diameter; red and 

 often spotted at maturity; thick-skinned; nearly free from bloom; 

 flesh bright yellow, juicy, acid; used for jellies; stone oval, 

 rounded at apex, %-l inch long. 



TWIGS. Slender; glabrous; bright green at first, becoming 

 orange-brown and marked by minute, circular, raised lenti- 

 cels; sometimes spiny-tipped. Winter buds: terminal absent, 

 lateral Vq-I^ inch long, acute, chestnut-brown. 



BARK. Up to Vi inch thick; dark brown, tinged with red; 

 outer layer forming persistent plates. 



WOOD. Heavy; hard; close-grained; strong; heartwood dark 

 brown, tinged with red; sapwood thin, lighter colored. 



SILVICAL CHARACTERS. Intolerant; on moist bottom- 

 lands to banks of intermittent streams on dry uplands and 



mountain slopes. 



* * * 



Canada Plum 



Prunus nigra Ait. 



The Canada plum is very similar to the American plum and 

 is often classed as a variety of it. It diff'ers in having leaves with 

 small rounded teeth and bi-glandular petioles. Canada plum 

 ranges from New Brunswick to southern Manitoba and south 

 to New York, Indiana, and North Dakota. The garden plum, 

 P. domestica L., while native to Europe and Asia has escaped 

 through much of North America, as has the BuUace or Damson 

 plum, P. institia L. 



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