CHAPTER XV 



BOTANY OF THE BRAMBLES 



A bramble is any plant of the genus Rubus. 

 According to this definition, there are not less 

 than 400 species the world over, and con- 

 servative authorities describe that number to 

 which more than 3000 species names have 

 been applied. To add confusion to the 

 classification of the brambles, there are many 

 hybrids. Few of this vast number of species 

 and hybrids are cultivated for their fruits, 

 and not more than twenty or twenty-five are 

 found in orchards and gardens. These culti- 

 vated brambles pass under several group 

 names, commonest of which are blackberry, 

 dewberry, Himalaya berry, loganberry, low- 

 berry, raspberry, and wineberry. Less com- 

 mon brambles are the cloudberry and salmon- 

 berry. 



The fruits of brambles are known by all 

 as berries. The berry of a bramble is an aggre- 

 gation of drupelets, each drupelet a carpel. 

 At maturity, the drupelets composing a berry 

 are coherent in all pomological brambles. In 

 blackberries and dewberries, the drupelets ad- 

 here to the torus, which at maturity separates 

 from the plant; this torus is the familiar core 

 of these fruits. In the raspberry, the mass of 

 drupelets separates from the torus, forming a 

 hollow, thimble-like fruit. 



There are probably a thousand or more 

 cultivated varieties of the several brambles. 

 To classify the species and their varieties, 

 some of which show but few and slight differ- 

 ences, requires intimate knowledge of the 

 morphological characters which can be used 

 for classification. 



CHARACTERS USEFUL IN CLASSIFYING BRAMBLE- 

 FRUITS 



The plant. 



The canes of brambles, usually woody but 

 sometimes herbaceous or semi-herbaceous, 

 spring from perennial rootstocks. The first 

 year's growth is a simple or slightly branched 

 stem which bears leaves only. This yearling 

 stem is the turion of the botanist, the sucker 

 of the fruit-grower. The second year the 

 turion becomes a cane and bears fruiting 

 branches. The only exception to this manner 

 of growth in cultivated brambles is the ever- 

 bearing red raspberry, which bears fruit late 

 in the season on the turion. 



The manner in which plants naturally 

 propagate themselves offers a distinguishing 

 characteristic for several species, and obviously 

 is of much importance to the cultivator. Black 

 raspberries, the purple-cane raspberries, dew- 

 berries, and loganberries naturally reproduce 



from tips which curve over and take root in the 

 ground in the autumn. All other brambles, red 

 raspberries and blackberries being the most 

 conspicuous examples, reproduce from suckers. 

 These are the natural habits of reproduction; 

 the propagator may use layers and cuttings, 

 and by special treatment may induce a species 

 to change its natural method to suit his con- 

 venience. Some brambles, as the blackberry, 

 are largely propagated in the nursery from 

 root-cuttings. 



In describing the stems of brambles, differ- 

 ences in the turion and canes must be noted. 

 The two structures often vary distinctly in 

 habit of growth; one may be erect, the other 

 drooping. They often differ in cross-section; 

 the one may be cylindrical, the other angular. 

 One may be pubescent or spiny, the other 

 glabrous and spineless. The color of yearling 

 and of the two-year-old wood, and the amount 

 and character of the bloom may vary. With 

 both, whether stocky or slender, the shape 

 and the color are matters of major impor- 

 tance. If the stems are angular, the surfaces 

 of the faces must be noted, whether concave, 

 convex, or canalized; the character of the 

 angle, whether acute or obtuse, is sometimes 

 important. The canes of the Mammoth black- 

 berry are exceptionally thick and are covered 

 with small spines. 



Especial attention must be paid to the color 

 of the stems and to the bloom. The stems of 

 cultivated brambles may be tints and shades 

 of green, yellow, brown, red, and purple. 

 These colors may be dull or glossy. The 

 bloom is characteristic in many species in 

 amount and in constancy, although the pres- 

 ence or absence of bloom sometimes depends 

 on the location of the plant. 



Presence or absence of armament and the 

 character of the armament furnish information 

 of capital importance in distinguishing species. 

 All of the species of brambles are pubescent, 

 prickly or thorny, while the shoots of some 

 are both pubescent and prickly. One species 

 of blackberry, R. Millspaughii, Brit., is thorn- 

 less, and there are thornless varieties of thorny 

 species. In some species the prickles are of 

 equal size and the same form; in others the 

 prickles are of unequal size and of different 

 forms. In the European raspberry the prickles 

 are nearly straight and are slender; they are 

 much stiff er in the American red raspberry; 

 these structures are straight spines in the black 

 raspberry; and are stout and curved in most 

 blackberries and dewberries. It may be noted, 

 also, that the spines or thorns are regularly 

 arranged in some species and are not so in 



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