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Northern Ontario Plant Database
Plant DescriptionRubus idaeus L.En: wild red raspberry
Rosaceae (Rose Family) Click on thumbnail to see larger image.
General: A deciduous shrub, 1-2 m tall, with biennial, erect to slightly arching stems (canes). Spreading, underground stolons often form dense colonies or thickets. Young stems often glaucous, sparsely to densely armed with numerous slender prickles and glandular bristle-like hairs. Older stems purplish-brown, becoming smooth and brown after the bristle-bearing epidermis shreds off. Taxonomy: Rubus idaeus L. var. strigosus (Michx.) Maxim. is the red raspberry variety native across North America, while var. idaeus L. (the cultivated red raspberry) is a European native. Rare forms in eastern Québec and the Atlantic Provinces may lack bristles on the young canes or have amber-coloured fruit; see The Flora of Canada (Scoggan 1978: 957) or Gray's Manual of Botany (Fernald 1970: 821) for more details. Some texts recognize Rubus strigosus Michx. as a distinct species. Leaves: Alternate, pinnately compound, stalked (petiolate); vegetative canes (primocanes) have leaves with 3-5 leaflets (usually 5); when leaflets number 5, the middle pair is situated closer to the terminal leaflet than the lower pair; leaves of the flowering canes (floricanes) have 3 leaflets. Petioles are bristly, stipules narrow and deciduous. Leaflet blades lanceolate to ovate, 2-10 cm long; green and smooth to slightly hairy above, much paler beneath with grey to whitish hairs; leaflet bases wedge-shaped (cuneate), rounded, or slightly cordate; apices sharply pointed (acuminate); margins irregularly toothed (serrate) to coarsely lobed. Flowers: Bisexual, small, 0.6-1 cm across, nodding, axillary from upper leaves and in small terminal clusters (cymes) of 2-5 flowers; flower stalks (pedicels) are glandular-pubescent. Calyx green, glandular-pubescent, with 5 ovate spreading to reflexed lobes, white-pubescent on the inner surface; petals 5, white, oblanceolate, erect, 0.5-1 cm long; stamens numerous, erect; pistils numerous, superior, with styles persistent in fruit. Flowers bloom in early to mid summer. Fruit: A rounded, aggregate fruit, to 1 cm across, composed of a cluster of small drupes (an aggregate of drupelets), becoming red when mature; edible and juicy; easily separating from the narrow, conical receptacle. Fruits mature in late summer. Habitat and Range: Open and disturbed habitats, such as cut-overs, rights-of-way, burns, and roadsides. The wild red raspberry has a transcontinental range, extending from Labrador to Alaska, and occurs throughout Ontario. Similar Species: The wild red raspberry is the only native raspberry in northern Ontario; the black raspberry (Rubus occidentalis), with blackish fruits and prickly, glaucous stems, occurs only in southern Ontario. Raspberry canes are similar in appearance to those of some blackberries, but blackberries can be distinguished by their palmately compound leaves and have purplish-black aggregate fruits that do not separate from the receptacle. Thimbleberry (Rubus parviflorus), found in northern Ontario, and the purple-flowering raspberry (Rubus odoratus), restricted to southern Ontario, differ by their simple, palmately lobed leaves. Internet Images: Other form for Virginia tech (both work):
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