I was out snowshoeing, scanning the edge of a field for signs of mammals and listening to chickadees going about their day, when a shrub clump caught my eye. Let's see how easily we can figure out who this is.
A great book for shrub mysteries like this is The Shrub Identification Book by George Symonds. The book is a visual guide, with a separate section each for comparing leaves, flowers, fruits, bark, etc. The book has a twig section with 15 pages for shrubs with alternate-branching, and 6 pages for those with opposite-branching (which our mystery shrub has).
Browsing the 6 pages for a visual match leads quickly to Viburnum, and we are forwarded to the master pages get more specific. Here, we compare various features of just Viburnums. Two types stand out as candidates for our shrub: Withe-rod (Viburnum nudum*) and Nannyberry (V. lentago).
From here, we can visit the GoBotany profiles for Nannyberry and Withe-rod and learn (in a section called Sometimes Confused With) that these two native shrubs can be told apart by the presence (or absence) of a stalk on the flower cluster. Luckily, the clump I found had plenty of dried flower clusters available, and the stalks on them reveal this plant as Withe-rod.
In the green season (which, dare I say, isn't too far away), other clues will be available, namely the leaves, which are sharply fine-toothed in Nannyberry and have irregular, blunt teeth in Withe-rod. And since both species produce edible fruit, it is worth recognizing these clumps on the landscape and making a mental or physical note to check back come fall.
*The book refers to Withe-rod as V. cassinoides, but many botanists (including those at GoBotany) now consider this a subspecies of V. nudum).