Rubus

  • Authority

    Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

  • Family

    Rosaceae

  • Scientific Name

    Rubus

  • Description

    Genus Description - Hypanthium small, flat to hemispheric; sep usually 5, valvate, spreading to reflexed, commonly with a shortly caudate tip; bractlets none; pet as many as the sep, erect or spreading, spatulate to obovate or elliptic; stamens numerous; pistils numerous, inserted on a convex to conic receptacle that often elongates in fr; ovules 2, collateral, only one maturing; style filiform or clavate; fr a cluster of drupelets, falling together (or sometimes separately), the receptacle falling with the cluster of drupelets or remaining attached to the pedicel; shrubs or less often perennial herbs, very often prickly, with simple or more commonly compound, serrate or lobed lvs and small to large, perfect or unisexual, white to pink or red fls; infl determinate, but commonly with the aspect of a raceme or corymb or panicle; x=7. 200+, cosmop.

  • Discussion

    In subgenera Rubus and Idaeobatus the plant sends up from a perennial base a series of biennial stems. During their first year these are termed primocanes; they are usually unbranched and normally do not fl. During their second year they are known as floricanes; they increase no more in length, but emit a number of short lateral branches with a few lvs and usually a terminal fl or infl. The lvs of the primocane are compound; those of the floricane are often partly simple, and often of a different shape.

    Most of the spp. of subg. Rubus grow in disturbed habitats, often representing an early stage in plant succession. Different species may grow intermingled in such places. Some of the same species also grow in more stable habitats, with some sorting out of species by habitat.

    The taxonomy of Rubus is complicated by hybridization, polyploidy, and apomixis. The subgenus Rubus (blackberries) is particularly difficult, and the conservative treatment here presented is subject to extensive change when a proper biosystematic study can be made. Some of the many names listed in synonymy should probably be transferred to the partial list of putative hybrids, hybrid segregates, and local populations of hybrid origin presented below.

    R. ×aculiferus Fernald = R. allegheniensis × setosus
    R. ×adjacens Fernald = R. hispidus × setosus
    R. ×alter L. H. Bailey = R. hispidus × setosus
    R. ×arcuans Fernald & H. St. John = R. recurvicaulis × setosus   
    R. ×bicknellii L. H. Bailey = R. recurvicaulis × setosus
    R. ×biformispinus Blanch. = R. allegheniensis × hispidus
    R. ×biformispinus Blanch. = R. allegheniensis × hispidus
    R. ×blanchardianus L. H. Bailey = R. hispidus × setosus
    R. ×electus L. H. Bailey = R. allegheniensis × hispidus              
    R. ×glandicaulis Blanch. = R. allegheniensis × setosus              
    R. ×harmonicus L. H. Bailey = R. hispidus × setosus         
    R. ×jacens Blanch. = R. hispidus × setosus
    R. ×jactus L. H. Bailey = R. allegheniensis × hispidus [Continued]

  • Common Names

    bramble