Rubus bloxamii – Series Radulae

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A white-flowered glandular bramble with hairy, pruinose stems and distinctive shredded leaflets. It is locally frequent but patchily distributed in central southern England and the Midlands. It is mainly a woodland edge and hedgerow species.

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Panicles have a compact rounded head of flowers on short peduncles, with some longer, strongly ascending peduncles lower down. The rachis is slightly flexuose, densely hairy with numerous short-stalked glands and frequent fine prickles mainly near the top (also short pricklets and acicles amongst the hairs).

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Flowers are about 2-2.5cm diameter, with white (sometimes may appear very pale pink in bud), broadly elliptical or obovate petals 13-14 x 8-9mm (to 8-10 x 5-7mm in shade-grown specimens). Petals are rarely slightly notched. Sepals are broad, long pointed, pubescent, with very short-stalked glands and acicles. They are generally patent at flowering (when the whitish pubescence inside is particularly noticeable) but may become reflexed after the petals have dropped. They are not conspicuously white-bordered (only very narrowly so).

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The carpels and receptacle are hairy (long pilose hairs around the base of the carpels). Styles are pale yellow, usually with a hint of pink near the base (just visible in the photos below). This species will key correctly using Edees & Newton if the styles are taken as being green. The stamens are level with or distinctly shorter than the styles; they are usually glabrous but sometimes slightly hairy.

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Leaves have 3-5 mid-green leaflets which are sparsely downy above. The petiole is usually longer than the basal leaflets. The leaflets are rather bluntly and shallowly serrate, with broad teeth, but the upper half is deeply incised and compound-serrate, giving a distinctive shredded appearance (especially on the terminal leaflet which is also rather truncate above). The terminal leaflet has a long, sometimes twisted, cuspidate apex and a subentire to emarginate base. Its size can vary but typically is quite large, about 8-10 x 6-8cm.

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Leaflets are green and thinly pubescent below.

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The first-year stem is hairy with long straight or slightly curved slender declining prickles. The longest prickles are on the angles, and grade into shorter pricklets on the faces, some of which are gland-tipped. There are also numerous (or sometimes sparse) subequal stalked glands, but this species does not have the abundant even-length glands giving the rasp-like feel of typical Radulans, and it is somewhat intermediate to the Hystrices. The armature in this species can be quite variable and like all brambles can be much reduced in shade-grown specimens.

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The stem is usually distinctly pruinose and may eventually turn a dull purple colour. It is bluntly angled with flat sides.

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