Flower:

Clusters of 1 to 3 short-stalked flowers arising from leaf axils all along branching stems. Flowers are ¼ to 1/3 inch long, generally bell-shaped, with 5 short, erect, greenish-white petals that are sometimes tinged with purple. Inside the tube are 5 creamy-tipped stamens that are as long as or slightly longer than the petals. In the center of the tube is a green style, as long as or slightly longer than the stamens; the lower half is densely covered in long, spreading hairs. The calyx cupping the flower is light green and hairless, the 5 sepal lobes rather petal-like, longer than the stamens and much showier than the actual petals. Sepals are oblong with rounded tips, erect to widely spreading, greenish white and may be pinkish to purplish at the base. Between the calyx and flower stalk is a smooth, green ovary. At the base of the flower stalk are small, egg-shaped bracts that are finely hairy especially around the edges, and often glandular-hairy. Flower stalks are up to ¼ inch long and smooth to sparsely hairy.

Leaves and stems:

Leaves are 2/3 to 1½ inches long and about as wide, round to kidney-shaped in outline, with 3 to 5 lobes that may be further divided into shallow lobes with coarsely toothed edges, the teeth rounded or pointed. Leaf bases are mostly straight to somewhat heart-shaped. Veins are prominent and radiate from the base.

The upper surface is variously hairy and may also be covered in glandular hairs; lower surface is glandular and densely covered in short, fine hairs. Leaf stalks are up to ½ inch long and covered in a mix of short, fine hairs and long, spreading hairs.

First year twigs are green, minutely hairy and covered with prickles, with 1 to 3 larger spines at the leaf and branch nodes. Upper stems become gray with a thin bark that flakes away. Prickles and spines may shed on upper stems but usually persist on lower stems. Older, lower stems are gray and rough textured. Stems are erect, arching or sprawling, rooting at the nodes and may create small colonies or thickets

Fruit:

Fruit is a smooth, round berry ¼ to ½ inch in diameter that ripens from green to reddish purple or purplish black.

Notes:

The Ribes species consist of both gooseberries and currants. Gooseberries are distinguished by at least some stems having spines or thorny prickles, which currants lack, and clusters of only 1 to 4 flowers, where currants have racemes of 6 or more flowers. Swamp Gooseberry (Ribes hirtellum) is most similar and several references state distinguishing it from Northern Gooseberry can be difficult; we noted several differences from our own observations, though we only sampled a few small populations and recognize there may be natural variations where traits will overlap, and the two may hybridize which makes everything more challenging: R. oxyacanthoides leaves are straight to heart-shaped at the base and one or both surfaces are glandular, where R. hirtellum leaves are straight to wedge-shaped at the base and surfaces lack glands or glandular hairs. The stamens of R. oxyacanthoides flowers are barely longer than the petals, where R. hirtellum stamens are much longer than the petals. R. oxyacanthoides stems are moderately to densely prickly with spines and prickles mostly persisting except in the uppermost stems, where R. hirtellum is more sparsely prickly, with most of the prickles and spines shed except towards the base of lower stems. There are 5 recognized varieties of R. oxyacanthoides, most of which are more western species and distinguished by a variety of characteristics; var. oxyacanthoides is the most common, found across Canada and into the northern US, including Minnesota. It is not considered rare in the state, but is listed as a Threatened species in Wisconsin.