Northern Spicebush, Lindera benzoin, one of those forest bushes that we squirrels have to skirt when running along the ground, and seems all but invisible to us. Except in the spring. Then, the branches are covered in small yellow flowers. And bees.
Both the male and the female plants that will flower, but only the female plants will set the fall berries. Apparently, there is a minute difference in the flowers to tell them apart, and they don’t set berries for a few years, so you humans are on your own for figuring this one out. Buy a lot of them? The bush grows 6 to 12 feet high and will tolerate a partly sunny location. Because it blooms in April, it serves bees in that early period when they are rebuilding their nectar stores and raising brood.
The Honeybee Conservancy has a lovely post on Northern Spicebush, showing its many seasonal colors off.
Spicebush is also the food plant of the Spicebush Swallowtail caterpillar, so plant a few extra bushes if you have room!