Research shows that there are about 10 species of hemlock. In appearance, the reddish-brown seeds are long and slender with a pinkish-brown wing. The eastern hemlock can grow over 100 feet tall, whereas the western hemlock can exceed 200 feet. When the bark is cut, the freshly snapped piece is white with woody sheets that are used for a wide range of purposes. They are usually populated in mixed forests in the mountains of SW China. However, the eastern hemlock has a longer lifespan--over 900 years. Both species do best in cool, moist environments. Rich in tannin, the bark of both species used to be a major source of the substance for the tanning industry. Hemlock is known for its dense, wet habitats, constituting dry, rocky soil. The western hemlock grows in the states of California, Oregon, Washington, Idaho, Montana and Alaska as well as the Canadian provinces of British Columbia and Alberta. Botanically named Tsuga caroliniana, Carolina hemlock tree is a conifer species, belonging to Pinaceae family. Both have small, flat needles that grow in two rows along each branch. Copyright 2020 Leaf Group Ltd. / Leaf Group Media, All Rights Reserved. Mountain hemlock (Tsuga mertensiana), also known as, black hemlock and hemlock spruce, is a humungous tree with an ability to grow 40 m tall and 150 cm wide. Scientifically called Tsuga Canadensis, Eastern hemlock is a slow-growing plant that takes almost two decades to reach its ultimate height of 40 feet and width of 25 to 30 feet. The shoots feature pollen cones that are usually dull purple in color and about 6mm in length. Due to its hardiness, the shade-tolerant tree is also able to tolerate light drought conditions. The cones of both trees hang from the ends of the branches. These small cones have barely-visible scales which are dark purple as they burst into shape but turn into a reddish brown color after pollination. Ever wondered where you can find these oldest hemlocks? Both the inner and outer bark varies in length but is usually blackish to reddish brown in color with irregular scales. Its easily worked wood is used to make doors, windows, kitchen cabinets, flooring and a variety of other items for housing construction. According to the Western North Carolina Nature Center, one specimen is known to have lived 988 years. That’s because of the mediocre quality of the wood and the rare population of the hemlock. The eastern hemlock grows in the Canadian provinces of Nova Scotia, New Brunswick, Quebec and Ontario. Known as Tsuga in Japanese, hemlock is an evergreen tree that belongs to the pine family and the subfamily – Abietoideae. The tree also produces small greenish-red seed cones in abundance. Related: Types of Mesquite Trees | Types of Redbud Trees | Types of Arborvitae Trees | Types of Fig Trees. The bark of this tree is considered to be diaphoretic, astringent, and diuretic in nature. We may be paid compensation when you click on links to those products and/or services. Related: Types of Elm Trees | Types of Willow Trees | Types of Locust Trees. The good news is that it is the only type of hemlock that is supremely resistant to hemlock woolly adelgids. This multi-stemmed tree has a dense crown which is needle-like in appearance. The fact that it can develop into a 100-feet tall tree, not many people are successfully able to incorporate this giant tree into their landscape. Often remarked for resembling Eastern hemlock, Caroline hemlock is different in the sense that its seed cones are longer than Tsuga Canadensis.