Nature Notes: Common Winterberry
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By Ed Robinson
Autumn will soon leave our forests bare. With winter on the way, we need some color to brighten our days. Fortunately we can enjoy a lovely native plant, the common winterberry. Even better, the bright red or orange berries will be on the shrub deep into winter before the birds finish them off.
Winterberry (Ilex verticillata) has an extensive range across the eastern US and Canada, as far south as Alabama. It is sometimes called by other names such as black alder, coralberry or swamp holly. It is a member of the holly family, with a bright green leaf, but the leaves are not evergreen – in the autumn, they turn dark and fall to the ground. Given the right soil conditions, and enough moisture, the multi-stemmed winterberry will reach up to 15 feet tall and may spread into a dense thicket.
The leaves unfold in early spring, and tiny blossoms appear from April through June, depending upon location. The flowers are tinted from light green to light yellow, with as many as 12 in a cluster. There is a small amount of nectar in the blossoms, so honey bees and butterflies benefit from this plant. If there are male and female plants in the population, pollination takes place and the quarter inch diameter berries will develop by late summer.
While beautiful to look at, winterberry also serves an important role in feeding wildlife. The fruit is consumed by nearly 50 different species of birds, from wood thrushes and eastern bluebirds to robins and turkeys. Small mammals, like raccoons, also eat them, and white-footed mice enjoy nibbling on the tiny seeds. Rabbits, hares, deer and moose will browse on the bark and buds of young winterberry. I always wondered why the berries stay on our bushes into late winter. It turns out the berries are low in fat, so the birds leave them until late in the season when other more nutritious foods are scarce.
This ornamental plant is a favorite for native landscapers, since it will grow in full sun or moderate shade, and it can handle damp locations to sandy or grassy areas. It is also quite hardy, tolerating northern winters (up to zone 3), and it suffers from few diseases or pests. You can grow them from seeds, but because of the need to ensure the presence of male and female plants, it is probably easier to buy stock from a knowledgeable and reliable nursery. Then you can use the beautiful cuttings in your seasonal floral arrangements, but please leave a few berries for the birds!