CRATAEGUS 115 



g. Crown more symmetrical, usually 

 rounded or conical in well-developed 

 plants. Branches more numerous and 

 intricate. 



h. Trees up to 10 m.tall with wide- 

 spreading branches; youngest 

 branchlets reddish brown. 



Series 11. Coccineae (C. pedicel- 

 lata Sarg. , etc. ) 

 h. Small trees seldom over 5-6 m.tall, 

 with round or conical crowns; 

 branchlets soon gray. 



i. Bark close, slightly fissured 

 and broken into small brownish - 

 gray scales, growing usually in 

 low moist or flat woods. 

 Series 10. Silvicolae. (C_. 



iracunda Beadle, etc.) 

 i. Bark becoming slightly scaly, dark 

 gray-brown, growing usually in 

 upland thickets or rocky ground. 

 Series 8. Rotundifoliae. (C_. 



chrysocarpa Ashe, etc.) 



POTENTILLA L. (Rosaceae) 



Small deciduous shrubs (mostly herbs). Twigs very slender, 

 nearly round, with quickly exfoliating bark;. pith small, round, 

 brown. Buds relatively large, solitary, sessile, oblong, with 

 about 4 striate scales. Leaf-scars alternate, very small, round, 

 on the end of the clasping 3-nerved leaf-base; bundle-trace 1; 

 stipules persistent. 



1. P. fruticosa L. Shrubby Cinquefoil. Low'bushy shrub 

 0. 2-1 m. high, the outer bark pale, shreddy. Open ground, Labra- 

 dor to Alaska, south to Pennsylvania, Iowa, South Dakota, Arizona 

 and California. 



RUBUS L. * (Rosaceae) 



Rather soft-wooded usually deciduous shrubs, mostly armed 

 with prickles, erect,trailing, or scrambling over supports. Shoots 

 moderate, often angled, pith relatively large, round or angled, 

 continuous. Buds moderate, sessile, oblong-ovoid. Leaf-scars 



* Based on data furnished by H. A. Davis 



