Today I noticed this bush with red berries growing on a steeply sloping bank of the stream. It has 3-lobed leaves with grooved stalks, and the leaf-stalks have little green bumps on them that I first mistook for aphids, but on closer inspection I found they are part of the plant. I think this shrub must be Viburnum trilobum (high bush cranberry), which my tree ID book says has club-shaped glands on the leaf-stalks, whereas the very similar Viburnum opulus var. opulus (European high bush cranberry) has saucer-shaped glands.
Armed with my new ID knowledge, I went to look at the "native Viburnum trilobum" that I bought from a nursery several years ago and planted in my garden. It has no bumps on the leaf-stalks, just saucer-shaped marks. I was duped!