Key to Wisconsin Shepherida

Author: John G. Zaborsky

• 1a.Leaves covered with silvery scales on both surfaces; branchlets silvery; thorns usually present; flowers opening before the leaves expand S. argentea

• 1b.1. Leaves greenish above with sparse white stellate hairs, lower surfaces densely covered with white stellate hairs and scattered coppery scales; branchlets coppery; thorns absent; flowers opening while the leaves are ¼ to ½ expanded S. canadensis