Hemlock spruce is a coniferous tree native to Canada and the northern regions of the Eastern United States. This evergreen can attain a height of 100 feet (30 meters) or more at maturity, with a spread of 30 feet (9.1 meters). Its trunk is approximately 5 feet (1.5 meters) in diameter. Known by the scientific name Tsuga canadensis, this tree is also commonly known as Canadian hemlock and eastern hemlock. The hemlock spruce cannot tolerate warm temperatures; it thrives in cold climates.
Lone specimens sport long branches that may droop to the ground, but when growing in dense forests, the branches of the hemlock spruce only grow near the top of the trees. The needles of the hemlock spruce are dark green and typically vary in length between 0.25 and 0.75 inches (0.6 and 1.9 centimeters). These needles have two white lines underneath. Brown cones of approximately 0.75 inches (1.9 centimeters) hang under the branches.
The hemlock spruce grows well in shade and has a conical shape that makes it an attractive plant in the landscape. It is commonly grown as a specimen plant but can also be planted in a row and trimmed for use as a privacy hedge. Unfortunately, the hemlock spruce is threatened by the adelgid, an insect that kills the tree by sucking out the sap. Many trees have been decimated by this pest. Whole mountainsides covered with dead hemlock spruces can be seen in the Smoky Mountains and throughout the Appalachians.
Hemlock spruce has been used to make various products. Its antiseptic properties and fresh aroma have made it a popular ingredient in cleaning products for the home. This type of spruce is also commonly used for lumber. An extract from the bark is used to tan shoe leather, and the needles are an ingredient in spruce beer. An essential oil distilled from the branches and needles has been used for many years as a folk medicine known as Balm of Gilead, spruce oil, and hemlock oil.
This oil is used topically to treat the pain of arthritis and sore muscles. A tea made from the twigs and bark is effective in the treatment of urinary problems. This tea can be used topically to speed the healing of skin ulcers, abrasions, and other external wounds. The tea can also be gargled to treat canker sores and sore throats. Pregnant women should never use hemlock spruce or any other folk remedy without first consulting a doctor.