In 1888, the female flowers or cones of a Nootka Cypress were fertilized by pollen from a Monterey Cypress. The two parent species would never have met in the wild as their natural ranges are 1000 miles apart(the female from Alaska and the male from California). But the original progenitors were growing close together in a private garden in Park Wood, Leighton Hall in the South of Wales. This unusual act of reproduction is called intergeneric crossbreeding and resulted in a hybrid called the Leyland Cypress or X Cupressocyparis leylandii. The Leyland cypress was named after it's discoverer C.J. Leyland.
The six seedlings Mr.Leyland discovered were sterile hybrids. Thus, there are no naturally occurring Leyland cypress. They must be propagated by rooted cuttings. From this humble beginning, the vigorous hybrid has become the most common tree in Britain(according to the Royal Forestry Society). In 1941, rooted cuttings arrived in the United States via California. Then in 1965, they arrived in South Carolina, where local entrepreneurs soon decided they would make great Christmas trees.
This conifer owes its popularity to several attributes. This tree can survive temperatures as low as 0 degrees Fahrenheit. It is extremely fast growing, resistant to pollution and salt water, and thrives on a variety of soils and sites. It is extremely suitable as a quick-growing hedge(growth as much as 4 feet a year is not unheard of). The Leyland cypress is very disease resistant. However, several diseases and some root rots have become more common recently.
The foliage of the Leyland cypress varies somewhat from one cultivar to the next. In general it tends to be arranged in irregularly flat planes with a dark green to gray color. The shoots branch repeatedly and have a contrasting mahogany color except at the tips. The trees have little aroma.
The bark of the Leyland cypress has a skin-like texture and is quite delicate. It can grow to heights of 138 feet.
Sources:
Virginia Christmas Tree Growers Association -http://www.vctga.com/
The Royal Forestry Society - http://www.rfs.org.uk/
North Carolina State University - http://www.ces.ncsu.edu/