Description
Corylus – Filbert – Hazel –
There area bout 15 species of deciduous trees and large shrubs, in this genus. They occur in the Northern Hemisphere, usually found in woodland. They have alternate, rounded or oval to ovate, strongly veined, toothed, leaves, sometimes with heart shaped bases. Hazels are grown for their foliage and yellow male pendulous catkins, borne before the leaves in early spring. Female flowers are inconspicuous, small greenish clusters at the branch tips on previous years growth. Male and female flowers grow on the same plant. Cultivars of several species listed below also produce husked, edible nuts. Smaller hazels are best grown in a shrub border, the larger species and cultivars are excellent specimen trees.
Grow in fertile, moist but well drained soil in sun or partial shade, they are ideal for alkaline or chalky soils. Grow variants with colored leaves in full sun.
Prone to powdery mildew, blight, canker, dieback, mushroom root rot, fungal spots, Gymnosporangium rust, bud mites, tent caterpillars, and webworms.
C. cornuta var. californica – Beaked Filbert – This upright, deciduous shrub grows 25′ feet tall and wide. It produces oval, toothed, serrated, mid green leaves, 1 ½-4 ½” long. In early spring it bears pendent, yellowish brown catkins, ½-1 11/4″ long. In autumn it bears edible nuts, ½” long, with husks forming narrow beaks, extending 3/4- 1 ½” beyond the nut.
Zones 5-7
