Tsuga canadensis - Eastern Hemlock

Tsuga canadensis, also known as the Canadian hemlock or Eastern hemlock, is a slow-growing conifer that can reach large dimensions over time. Its habit is pyramidal to conical and its foliage, ranging from medium green to dark green, is slightly glossy. This imposing tree is therefore best planted in large gardens or parks, as a standalone specimen. It has specific requirements for its living conditions, being sensitive to drought, wind, and urban pollution. Additionally, it does not tolerate strong sunlight and requires neutral to acidic soil. It is a forest species that will interest knowledgeable enthusiasts. 

Tsuga canadensis is an evergreen conifer of the Pinaceae family, native to eastern Canada and the United States, where it often grows in mixed forests and maple groves, always in shade. This species slowly reaches a height of 30m (98ft) with a width of 8 to 10m (26 to 33ft), with a trunk diameter of 1m (3ft), and can live for 600 years. It is a very hardy conifer that prefers fertile and moist soils and cannot tolerate drought or direct sunlight. Its roots are shallow and spread out, making it susceptible to wind.

This is a typical forest species that belongs in large parks and gardens. It grows slowly, with a distinctly pyramidal habit in its early stages, which can then evolve into a more spreading conical shape. The long branches start at right angles to the trunk, and as they are quite flexible, their tips hang down, giving it a typical silhouette. The foliage consists of small needles that are 2.5cm (1in) long and 1.5cm (1in) wide. Two bands of light grey to white stomata adorn the underside of the leaves. During bud break, the needles are light green and darken afterwards. The bark of the tree starts as orange-brown and turns brown-black. Flowering occurs in May, but it is quite insignificant, with small yellow-green flowers of about 4mm (1in) going unnoticed among the foliage. They are followed by small, brown, pendulous cones of about 2cm (1in) in length. In our climate, this species reaches approximately 25m (82ft) in height at maturity, with a width of about 8m (26ft). The tree is extremely hardy (beyond -30°C (-22°F)).

Reserved for large spaces and cold climates, Tsuga canadensis will form beautiful specimens when planted in isolation, provided it is given the required climatic and soil conditions. In sufficiently moist soil, it can also be planted with Nyssa sylvatica, whose fantastic reddish-orange autumn colours will be enhanced by the contrast with the dark green of Tsuga. The Virginia tulip tree (Liriodendron tulipifera), another tall tree with beautiful autumn foliage, yellow this time, will complete this trio. A smaller tree, Cercidiphyllum japonicum, the caramel tree, will enrich this group of deciduous trees with interesting and decorative foliage in autumn, leaving the winter to Tsuga canadensis to occupy the scenery with its evergreen branches.