Leyland Cypress

Leyland Cypress - X Cupressocyparis leylandii

The Leyland Cypress has recently been cast in the role of the villain! This hybrid tree is now one of the commonest in Britain. Millions have been planted for quick-growing garden hedges.

A number of disputes between neighbours over boundary hedges of Leyland Cypress have hit the news recently and the Government has been asked to ban growing this vigorous hybrid for hedges. Too many are planted close to houses and soon produce problems with intense shade, root damage and even the possibility they may topple onto buildings.

The Government has responded by publishing the report of the Department of Environment study 'High Hedges: possible solutions'. It has also published a Summary of Responses to the Consultation Paper on the topic.

Hedgeline is an organisation founded to help people who are affected by unreasonably high hedges, often the result of neglect by neighbours. Leyland Cypress is the commonest species involved.

The Leyland Cypress is not found in the wild. It came about because man brought together two species from distinct genera of plants from different regions that would otherwise never have met. They interbred and produced this new vigorous hybrid.

Although hybrids occur quite frequently between closely related species, it is not often that a cross occurs naturally between trees of different genera.

The parent trees came from opposite ends of the Pacific coast of N. America - the resulting cross between a Monterey Cypress (Cupressus macrocarpa) from California and the Nootka or Alaska Cypress (Chamaecyparis nootkatensis). The original progenitors were growing close together in a tree collection in Park Wood, Leighton Hall near Welshpool, Powys, adjacent to what is now the Royal Forestry Society's Charles Ackers Redwood Grove and Naylor Pinetum.

The cross occurred when the female flowers or cones of Nootka Cypress were fertilised by pollen from Monterey Cypress. That took place in 1888 on the Leighton Estate near Welshpool, Powys. The two parent species would never have met in the wild as their natural ranges are thousands of miles apart.

The hybrid was named after Christopher John Naylor (1849-1926), the eldest son of John Naylor (1813-1889) of Leighton Hall; Christopher John changed his surname to Leyland in 1891 on inheriting the Leyland Entailed Estates established under the Will of his great-great-uncle, which passed to him following the death of his uncle Thomas Leyland (née Naylor). His father, John, had only a year to live at the time the seedlings were first found and, although Christopher John had inherited Leighton from his father in 1889, in 1891 it was passed to his younger brother, John Naylor (1856-1906) and Christopher John himself went to Haggerston.

This rather lengthy explanation has been provided by the Naylor family in an attempt to refute the previously published notions that Christopher John was son-in-law and brother-in-law respectively of John Naylor (senior) and John Naylor (junior); this error seemingly crept in the article by the late Alan Mitchell and others, "The Clones of Leyland Cypress", published in the "Quarterly Journal of Forestry" in January 1964.

About 20 years later, a further cross occurred at Leighton Estate but the other way round when the cones of the Monterey Cypress were fertilised with pollen from the Nootka. The result of that cross was a second form, baptised "Leighton Green".

As a hybrid, these novel Leyland Cypress were sterile so all the trees we now see have resulted from cuttings originating from those few plants.

Several different forms or clones now exist including the golden "Castlewellan" one which originated from a single mutant tree in the arboretum of that name in Northern Ireland.

Leyland Cypress is light-demanding but is tolerant of high levels of pollution and salt spray. This hardy, fast-growing natural hybrid thrives on a variety of soils and sites making it very popular for hedges. Although widely used for screening, it has not been planted much for forestry purposes. In both forms of the hybrid, Leyland Cypress combines the hardiness of the Nootka or Alaska Cypress with the fast growth of the Monterey Cypress. In fact this is the quickest growing conifer in Britain, growing as much as 1.25m (4 feet) in a year. At Bedgebury Pinetum in South East England the Leylandii are 130 ft tall and still growing strong.

The scientific name of the Leyland Cypress is written as X Cupressocyparis leylandii. , the X denoting that it is a hybrid.