Brambles
Scientific name: Rubus L.
Diagnostic features
Deciduous or semi-evergreen shrubs, often spiny, or herbaceous perennials.
Leaves simple, ternate, pinnate or palmate.
Flowers solitary or in racemes or panicles, usually 5-merous.
Epicalyx absent.
Hypanthium flat, with receptacle usually extended upwards from centre.
Stamens numerous.
Carpels usually numerous.
Fruit a head of (1)2-many 1-seeded drupes.
Most of the taxa of Subgenus Rubus form an extremely complex, largely apomictic group (Section Glandulosus), often known collectively as Rubus fruticosus L. aggregate. Two other sections (Section Rubus and Section Corylifolii) are often included within this aggregate, but they are probably derived from ancient and some recent hybrids between it and Rubus idaeus and Rubus caesius respectively, and are here treated separately. Rubus caesiusforms a 4th section. Over 400 microspecies (331 currently) have been recognized in British Isles in these 4 sections together. In this work the microspecies of SectionRubus, Section Corylifolii and Section Glandulosus are not treated in full but, following the view of A. Newton and E.S. Edees, 11 rather ill-defined series, representing the main nodes in the spectrum of variation, are recognized in Section Glandulosus. These are keyed out in couplets 15-24 (See 'Key to taxa' or Text Key Page 2268), but most of the characters used are relative and a high level of success will be achieved only after much experience.
This Genus is keyed out on Page 2255: Rubus; Page 2307: Rubus and other genera and Page 2811: Fallopia & Rubus in the Text Key.
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