RUBUS 



RUBUS 



3031 



broad-lanceolate, usually pubescent and hairy on the 

 ribs beneath: infl. on elongated raceme-like cluster of 

 which the center or terminal fl. is commonly the oldest 

 (the long-cluster blackberries), or nearly as broad as 

 long, due both to shorter axis and longer lower pedicels 

 (short-cluster blackberries), sometimes with small Ivs. 

 intermixed (leafy-cluster blackberries), the rachis and 

 pedicels usually glandular-pubescent but in some forms 



or less recurving, the mostly stout prickles moderately 

 curved: Ifts. ovate, often cordate, glandular-pubescent 

 beneath: infl. mostly elongated and not leafy, glandu- 

 lar-hairy. Canada to N. C. and 111. With this group 

 are to be associated R. nigrobaccus, Bailey, R. sativus, 

 Brainerd, R. glandicauLis, Blanchard. 



The wild thornless blackberry, R. canadensis, Linn. 

 (R. MiUspaughii, Brit.), is a tall mostly weak-caned 

 entirely thornless species apparently not represented in 

 domestication, the frequent so-called thornless forms 

 of cult, blackberries being apparently unarmed off- 

 shoots of normally thorny kinds; this readily distin- 

 guished species, with narrow thin mostly glabrous Ifts., 

 is native in Canada and the northern states and in the 

 higher lands to N. C.; here are to be associated R. 

 Randii, Rydb., and perhaps R. elegantulus and R. 

 amicalis, Blanchard. 



The sand blackberry, R. cuneifolius, Pursh, growing hi 

 dry fields from Conn, to Fla. and La., appears not to be 

 in cult, or to have contributed to the admixture of the 

 garden blackberries. (Fig. 581, Vol. I.) It is a stiff and 

 thorny plant, usually not over 3-4 ft. tall, the prickles 

 many, mostly hooked, and very strong, the young 

 growths white-tomentose: Ifts. on bearing canes mostly 

 small and thick, wedge-oblong to wedge-obovate, obtuse 

 or nearly so, densely white-tomentose beneath, the 

 margins sharp-toothed: fl. -clusters 4-10-fld., short, 

 more or less leafy and thorny, the fl.-buds globular and 

 pubescent: fr. medium in size, firm, often sweet and 

 good. See discussion under R. Linkianus, No. 57. 



AA. Dewberries: plant trailing or strongly decumbent (often 

 trained to stakes or on trellises under cult.). 



B. The pomological dewberries of E. American origin. 



61. Cultivated American dewberry. A variable 

 group of American origin, from the native species: 

 trailing or prostrate plants, the weak slender canes 

 lying on the ground or sometimes making low mounds, 

 mostly prickly or thorny : Ifts. usually 3 : infl. short and 

 mostly interrupted or leafy, or the fls. axillary, pubes- 

 cent or glabrous: fr. blackberry-like. The native 

 sources of the dewberries are to be sought in the fol- 

 lowing more or less marked species-segregations; R. 

 procumbens, Muhl. (R. .vittdsus, Ait., not Thunb.) 

 (Figs. 3501, 3502), of the northeastern states and south 

 to Va., is the prevailing dewberry of open fields away 

 from the Coastal Plain, with canes usually several feet 

 long and usually bearing stout recurved prickles: Ifts. 

 usually narrowed at the base, nearly or quite glabrous: 

 fls. in the upper axils. Var. roribaccus (R. villosus var. 

 roribaccus, Bailey) is the Lucretia dewberry type. R. 

 invisus, Brit. (Figs. 3503, 3504; also Fig. 1250, Vol. 

 II). Probably has the range of R. procumbens: canes 

 strong and terete, somewhat ascending and often mak- 

 ing mounds or piles of canes and herbage, not very 

 prickly: Ifts. large, those on the sterile shoots with 

 large simple serratures: infl. dichotomous. R. geophi- 



3500. Rubus aUegheniensis (X}-s). No. 60. 



nearly or quite glabrous: fr. various, from long and 

 thimble-shaped to ovoid or nearly globular. The more 

 or less well-recognized wild native species-types, vari- 

 ously defined and re-defined, from which some or all 

 of the prevailing pomological blackberries are probably 

 derived, are as follows: R. argutus, link, an erect or 

 stout species with very prickly stiff sts., Ivs. relatively 

 small or medium-sized with short-pointed Ifts. and 

 thorny stalks and ribs, mostly not glandular short infl., 

 a prevailing group widely distributed from Canada to 

 X. C. and Iowa; with this group are probably to be 

 associated R. amnicolus. R. Andrewsianus, R. flori- 

 comus, Blanchard, and perhaps R. pergratus and R. 

 orarius. Blanchard. R. floridus, Tratt., a tall species 

 with branches often decumbent or strongly recurving 

 and stout curved prickles: Ifts. mostly narrow and 

 acuminate, somewhat pubescent be- 

 neath: infl. loose and leafy, with few 

 fls.: fr. elongated, the drupelets small. 

 Va.. south and west. With this, R. 

 betulifolius, Small, and R. lucidus, 

 Rydb., are probably to be associated. 

 R. fronddsus, Bigel., of medium height, 

 mostly erect but sometimes recurving, 

 the prickles straight only slightly 

 curved: Ifts. broad, becoming glabrate 

 above, velvety-pubescent beneath: infl. 

 short, villous, with a few simple Ivs. or 

 bracts. Canada to Va. and Kans. To 

 be associated with this group are R. 

 recurvans, R. arundelanus, R. philadel- 

 phicus, R. Rossbergianus, Blanchard. 

 R.Brainerdii,Rydb. R.allegheniensis, 

 Porter (Fig. 3500; also Fig. 578, Vol. 

 I). Of medium height, erect but more 3501. Rubus procumbens, a common northern wild dewberry (XJi). No. 61. 



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