Tsuga heterophylla - Western Hemlock

The Western Hemlock or Tsuga heterophylla is a beautiful evergreen tree native to America, which, in its native range, reaches considerable sizes and represents an important source of wood, especially for the paper industry. This powerful and graceful conifer has an open pyramidal crown with sparse horizontal branches. The flexible and light branches bear short, soft needles with rounded tips in a vibrant dark green colour. The tree becomes more slender over time, starting wide in its youth. It can thrive in all exposures, in cool and well-drained soil, neutral to acidic.

The Western Hemlock, also known as California Hemlock, Western Hemlock or New World Hemlock, is a tree species belonging to the Pinaceae family. Its natural distribution extends along the west coast of North America, from Alaska to California. Its distribution coincides with temperate rainforests; its entire range is within 100 kilometres of the west coast. It was introduced to Europe in 1851. It is cultivated in Western Europe for its wood, but it succumbs to severe cold in Central Europe and is only planted for ornamental purposes in parks. Although it is a climax species of old and mature forests, it exhibits some versatility in ecological resilience, particularly in its ability to recolonise damaged sites. This conifer reaches considerable sizes of 50 to 70 metres in height in its native habitat and exceptionally up to 2.7 metres in trunk diameter. It will reach 20 to 30 metres in height, and its crown will be 8 to 12 metres wide. Its thick, channelled bark is reddish-brown and darkens to grey over time. It has rapid growth, with sparse branches forming an open crown. The branches spread horizontally and have few lateral branches—their tips droop. The young branches are also strongly drooping. They are brown-yellow and pubescent. The blunt needles have finely toothed edges. The upper surface is shiny, dark green. The lower surface is covered with two rows of white-grey stomata. After inconspicuous flowering, short pedunculate and pendulous cones appear. The female cones, 20 to 25 mm in size, have rounded scales that are distinctly longer than wide.

Thriving in partial shade, this species also appreciates moist soils. The Tsuga heterophylla can grow in all exposures. It thrives in acidic to neutral, well-drained soil and requires moderate watering. This large tree with a wide crown is best suited for large spaces.