The Leyland Cypress, × Cupressocyparis leylandii (syn. Callitropsis × leylandii), often referred to as just Leylandii, is a fast-growing evergreen tree much used in horticulture, primarily for hedges and screens. Even on sites of relatively poor culture, plants have been known to grow to heights of 15 metres in 16 years. Their rapid, thick growth means they are sometimes used to enforce privacy, but such use can result in disputes with neighbours whose own property becomes overshadowed.