ROSACEA 357 



RASPBERRIES 



There are four well-known groups of cultivated rasp- 

 berries: black-cap, purple-cane, American red, and European 

 red. . 



Key to Principal Species of Raspberries 



Fruit purple-black, rarely yellow; propagating by tips, R. occidentalis 



(black-cap). 

 Fruit purple, dark red, light red, or sometimes yellow; propagating by tips 

 or suckers. 

 Stems stiflf and erect; fruit produced more or less continuously throughout 



the season, R. idaus (European red). 

 Stems more slender and drooping; fruit produced less continuously through- 

 out the season. 

 Stems bristly, not glaucous; fruit light red; inflorescence racemose, R. 



strigosus (American red). 

 Stems prickly, slightly glaucous; fruit dark red; inflorescence racemose- 

 cymose, R. strigosus X R- occidentalis (purple-cane). 



Rubus occidentalis. — The slender stems are often lo to 12 feet long, rooting 

 at the tip, sparingly supplied with small hooked prickles, and sometimes glan- 

 dular-bristly above. The leaves are trifoliate, stipulate, with oval or acumi- 

 nate, toothed leaflets, that are white-hairy on the under side. The inflor- 

 escences are dense, and corymbose. The flowers are on short pedicels; the 

 petals are shorter than the sepals. The black-cap raspberries are the most 

 important in this country. The species is found throughout eastern United 

 States, northward into Quebec and Ontario, and westward to Oregon and 

 British Columbia. 



Some of the western forms have been given distinct specific names {R. leu- 

 codermis, R. glaucifolius, R. bernardinus. 



Rubus idaeus. — The stems are stiff and erect, and furnished with prickles; 

 glandular bristles are never present except in some cultivated forms which 

 may be considered as hybrids between R. idcsus and R. strigosus; pubescence 

 occurs on peduncles, pedicels, petioles are nearly always flattened and slightly 

 curved. The thick leaves are white-downy beneath. The fruit is purple or 

 yellow and is produced throughout the season. The European raspberry is 

 not cultivated to any extent in this country at the present time. It is a native 

 of Europe and Asia. 



Rubus strigosus. — ^The stems are slender and bear stiff, straight or hooked 

 prickles; glandular bristles occur on peduncles, pedicels, petioles, and calyx. 

 The leaves are three- to five-foliate, with ovate or oblong-ovate, sharply serrate 



