Rubus divaricatus – Section Rubus
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This is a typical looking Section Rubus species, with suberect suckering stems up to about 1.2m tall, often forming large colonies. It is distinguished from others in the section by a combination of pink petals, bright reddish stems and strongly curved prickles on the stem and rachis. It is widespread in NW Europe, but in the UK is most frequent in the south, especially in parts of the New Forest, Hampshire. It is likely to predominantly be a heathland species.
The inflorescence is a short raceme, appearing corymbose, with a head of divaricately branched peduncles, each with 1-3 flowers. Below these are some narrow single leaflets and 3-foliate leaflets. The rachis has sparse to frequent simple hairs and scattered sessile or subsessile glands (more frequent on the pedicels). There are a variable number of gently curved to strongly hooked prickles.
Flowers are 2.5-3cm across. Petals are bright pink, though usually fade to pale pink when fully open. They are generally obovate in shape but appear to vary from relatively broad to quite narrow. The sepals are typical of the section, being thinly pubescent, especially at the margins, but shiny bright green in the middle, producing a white-bordered appearance. This is particularly noticeable on the unopened flowers, though is sometimes indistinct. Sepals are usually short pointed, patent at flowering, becoming erect and loosely clasping the developing fruit. Styles are green or pink at the base and yellow above, but on some plants the pigment is more pronounced, turning the styles completely pink, the filaments pale pink and the anthers a dark pinkish-brown colour. The anthers are usually glabrous but on one plant shown below were densely hairy. In common with most other section Rubus, the stamens splay outwards at flowering and the petals fall off easily. In fresh flowers the petals are concave and the stamens are clearly longer than the styles. The young carpels are glabrous or slightly hairy.
Plant with hairy anthers:
Leaves have 3-5 bright green leaflets, which are sparsely pubescent or glabrous above and thinly pubescent below. The petiole is relatively long in this species - up to twice as long as the basal leaflets. The terminal leaflet shape is narrowly elliptical to obovate with an emarginate to subcordate base and typically a shortly acuminate tip. Leaflets are often concave or with the sides folded inwards. Toothing is fairly coarse and uneven, somewhat incised. Older leaflets become plicate and moderately rugose.
Leaflet underside:
The first-year stem is green or more usually deep red, bluntly angled with round or flat sides. Older stems may have more pronounced ridges and grooves. They are sparsely hairy, becoming glabrous with age, moderately shining. A few sessile glands may be present. Prickles are moderately dense, equal to or longer than the stem diameter, mainly on the angles, curved to somewhat hooked, with a broad, flattened base and golden yellow tip.
