Arborvitae, also known as Thuja, is a genus of coniferous trees and shrubs in the Cupressaceae family, native to North America and eastern Asia. They are evergreen plants that can grow from 3 to 60 m tall. Most species have straight trunks covered with fibrous, reddish-brown bark. They are monoecious plants: the female cones are ovoid or oblong with 8-12 scales. They incorporate small, flattened seeds. The male cones are small, inaccessible, located towards the tips of the branches. They are ornamental trees, planted in gardens and parks. They can be found as solitary specimens or in groups, but especially as hedges.