About

Corylus colurna, the Turkish hazel, Byzantine hazel or Constantinople Hazel, is a species of hazel (Corylus) in the birch family (Betulaceae). It is native to the Balkan Peninsula and Western Asia, but has become widely introduced in other areas of Europe as an ornamental, particularly as a street tree. It typically grows 25–30 metres (82–98 ft) tall, with a slender growth form in its youth. Although the nuts are not commercially important, Corylus colurna is commonly used as a single-stemmed, non-suckering rootstock for common hazel (Corylus avellana) scions.

How to grow it

Corylus colurna has a medium growth rate. It is occasionally drought tolerant and alkaline soil tolerant. However, it prefers moist, well-drained soil, as well as full sun. Once established C. colurna is tolerant of heat, cold, and drought. There are no serious pests or problems with C. colurna.

Corylus colurna is not easily transplantable and will need extra watering in summer after transplanting. It will take about two years after transplant for the tree to become established and survive on its own. Corylus colurna has received the Royal Horticultural Society's Award of Garden Merit.

Where it grows

C. colurna is native to southeast Europe and southwest Asia, from the southern Balkans through northern Anatolia to the Caucasus. Although it has been reported from the mountain forests of northern Iran (Hyrcania and Turan) in the past, more recent surveys have failed to relocate it here, casting doubt over its continued presence in the region. Previously, the species was also considered to be native to the western Himalayas, but these populations are currently considered as constituting a different, though closely related species, C. jacquemontii.

Uses

Besides its use as a single-stem rootstock for C. avellana, C. colurna is widely cultivated as an ornamental tree in Europe and North America. It is very tolerant of difficult growing conditions in urban situations, which in recent decades has increased its popularity in civic planting schemes. Turkish hazel makes a good shade tree since it produces dense shade, and its narrow crown and ability to withstand air pollution make it well suited for use as a street tree in urban areas, or a specimen tree in parks. It makes a rather formal statement in the landscape due to the tight, consistently-shaped, narrow crown. Other landscape uses for C. colurna are for fruit, difficult and dry sites, and naturalistic areas.

Other Corylus plants

American hazelnut · Hazel · Chinese Hazel · Colchian Hazel · Beaked hazelnut · Corylus fargesii · Himalayan hazelnut · Siberian hazelnut · Indian Tree Hazel · Filbert · Japanese Hazel · Corylus wangii