Ilex verticillata, the American Winterberry, is a species of holly native to eastern North America in the United States and southeast Canada, from Newfoundland west to Ontario and Minnesota, and south to Alabama.
Other names that have been used include Black Alder Winterberry, Brook Alder, Canada holly , Coralberry, Deciduous Holly, Deciduous Winterberry, False alder, Fever bush, Inkberry, Michigan Holly, Possumhaw, Swamp Holly, Virginian Winterberry, or Winterberry Holly.
Ilex verticillata is a shrub growing to 1–5 metres (3.3–16 ft) tall. It is one of a number of hollies which are deciduous, losing their leaves in the fall. In wet sites, it will spread to form a dense thicket, while in dry soil it remains a tight shrub. The leaves are glossy green, 3.5–9 cm long, 1.5–3.5 cm broad, with a serrated margin and an acute apex. The flowers are small, 5 mm diameter, with five to eight white petals.
The fruit is a globose red drupe 6–8 mm diameter, which often persists on the branches long into the winter, giving the plant its English name. Like most hollies, it is dioecious, with separate male and female plants; the proximity of at least one male plant is required to pollenize the females in order to bear fruit.
Cultivation and uses 
Ornamental plant 
Ilex verticillata - the American Winterberry - is prized as an ornamental plant in gardens for the midwinter splash of bright color from densely packed berries, whose visibility is heightened by the loss of foliage; therefore it is popular even where other, evergreen, hollies are also grown. The bare branches covered in berries are also popular for cutting and use in floral arrangements.
It is a tough plant which is easy to grow, with very few diseases or pests. Although wet acidic soils are optimal, the winterberry will grow well in the average garden. Numerous cultivars are available, differing in size and shape of the plant and color of the berry. At least one male plant must be planted in proximity to one or more females for them to bear fruit.