Description of the American Hazelnut Shrub

Size and Form

• In terms of its potential size, the hazelnut requires some room to grow. The bush matures between 8 and 15 feet tall, with a width in the range of from 8 to 13 feet. This is a shrub featuring multiple stems from its root system. The hazelnut possesses a wide-spreading form, notes the University of Connecticut Plant Database, taking on a rounded appearance when mature. New growth develops from the roots, making pruning necessary to avoid thickets of hazelnuts from taking over an area.

Leaves

• The leaves on a hazelnut shrub grow from the twigs in an alternate pattern. They reach lengths between 3 and 6 inches long, with widths from 1 1/2 to 2 1/2 inches. The base of the leaf has a heart shape, but the entire leaf is oval in form. The stem, or petiole, attaching the leaf to the twig is short.The edges are serrated, and the leaf is a shade of dark green. In autumn, the hazelnut leaves turn different colors, including orange, yellow, red and purple.

Flowers

• The flowers of the hazelnut bloom during March and April. The Missouri Botanical Garden notes the hazelnut is a monoecious species, with the male and female flowers on the same shrub. Male flowers are yellowish brown. Known as catkins, they are between 2 and 3 inches long and quite showy. The female flowers are smaller and red, with little ornamental value.

Hazelnuts

• Once the female flowers of a hazelnut start to fade, they begin to develop into the nut. These nuts are up to 1/2 inch in length and have a shape resembling that of an egg. They nuts have a protective casing much like a husk. The modified leaves surrounding the nut, called bracts, feature ragged edges. The nuts ripen to the point that they are edible by September, with birds and small mammals such as squirrels eating them if you fail to pick them.