dwarf raspberry

LC - Least Concern

NNR - Unranked

SNR - Unranked

not listed

FACW - Facultative wetland

FACW - Facultative wetland

FACW - Facultative wetland

Dwarf raspberry is a perennial, low-growing, non-woody subshrub. It occurs in western Europe, throughout Canada, and in the United States in the northern tier of states south to New Jersey, Colorado, and Oregon. In Minnesota it is common throughout most of the state but absent in the west-central, southwest, and south-central counties. It is found in moist to wet woodlands and meadows and in various wetlands including shrubby swamps, bogs, and fens.

Dwarf raspberry rises on above-ground vegetative stems (stolons) from a root crown and a perennial, underground, horizontal stem (rhizome). The stolons are erect at first but soon recline, creep along the ground, and root at the nodes. They are slender, sparsely to moderately hairy, and 4″ to 80″ long. They do not have bristles, prickles, or glands, and are not covered with a whitish waxy bloom (glaucous). They are usually woody just at the base.

Single flowering stems rise from each lower node on the stolon and from the root crown. These stems are erect, leafy, softly hairy, and herbaceous, not woody. They may be 6″ to 20″ (15 to 50 cm) tall but in Minnesota they are usually no more than 12″ (30 cm) tall. They usually have no bristles or prickles, rarely they have a few bristles.

There are usually 2 to 5 leaves alternately arranged on the flowering stem. They are on hairy, ¾″ to 3″ (2 to 8 cm) long stalks (petioles) and are divided into 3 leaflets. Occasionally the two lateral leaflets are each deeply cleft into two lobes, making the leaf appear at a glance to have 5 leaflets. At the base of each petiole there is a pair of leaf-like appendages (stipules). The stipules are 3 ⁄16″ to ¾″ (5 to 20 mm) long. They may be inversely lance- or egg-shaped, widest beyond the middle; lance- or egg-shaped, widest before the middle; or elliptic, widest at the middle.

The terminal leaflet is rhombic to egg-shaped, 1½″ to 3″ (4 to 8 cm) long, and ¾″ to 1½″ (2 to 4 cm) wide. It is on a short 1 ⁄16″ to ¼″ (2 to 7 mm) long stalk (petiolule). The blade is wedge-shaped at the base and tapers to a narrow (acute) point at the tip with straight or concave sides along the tip. The upper surface is dark green, the lower surface somewhat lighter. Both surfaces are hairless or sparsely hairy. The margin is deeply toothed or doubly toothed with sharp, forward-pointing teeth except at the wedge-shaped base, which is untoothed. The lateral leaflets are smaller, asymmetrically egg-shaped, rounded at the base, stalkless or nearly stalkless, but otherwise similar.

In mid-May to late June 1 to 4 small flowers appear at the end of the upright stem and sometimes in the upper leaf axils. They are on long stalks (pedicels) that are moderately to densely covered with long hairs and are usually also sparsely to densely covered with stalked glands.

The flowers are ¼″ to ½″ wide and are not showy. There are 5 sepals, 5 petals, and numerous stamens. The sepals are green, softly hairy, narrowly lance-shaped or narrowly triangular, ⅛″ to ¼″ (3 to 7 mm) long, and strongly bent backward. The petals are white, rarely pale pink, narrowly inversely egg-shaped or spoon-shaped, and ⅛″ to ⅜″ (4 to 10 mm) long. The stamens are shorter than the petals.

The fruit is a bright red to dark red, globe-shaped, 3 ⁄16″ to 9 ⁄16″ (5 to 14 mm) in diameter aggregate of multiple drupelets. It matures late June to early August. When picked it does not separate easily from its core.

6″ to 12″ (15 to 30 cm)

White

Moist to wet. Woodlands, shrubby swamps, bogs, fens, meadows, and stream banks.

Mid-May to late June

Sources

2, 3, 4, 5, 7, 8, 24, 28, 29, 30.

Native

Common and widespread

Two varieties have been described, Rubus pubescens var. pilosifolius and R. p. var. pubescens. The former variety is common and widespread, the latter variety is restricted to Maine, Vermont, Quebec, and Newfoundland and Labrador. Most authors do not recognize any varieties.

Plant

Leaf

Fruit

Location: Fairview Twp, Cass County

Mistook this for a strawberry plant until the berries formed.