Tree Varieties
Colorado Blue Spruce
Colorado blue spruce, or blue spruce, is an attractive tree often used for Christmas trees or as ornamentals, particularly in the eastern United States and Europe. It is the official state tree of both Colorado and Utah. The species generally reaches a height of 65-115 feet at maturity with a diameter of 2-3 feet. It has a narrow, pyramidal shape and cone-shaped crown. As trees become older, they often take on a more irregular appearance. While blue spruce grows relatively slowly, it is long-lived and may reach ages of 600-800 years.
Leaves (needles) are 1-1 1/2 inches long on lower branches but somewhat shorter on upper branches. They are 4-sided and have a very sharp point on the end. It is this point which gives the species its name “pungens”, from the Latin word for sharp as in puncture wound. Needles are generally dull bluish-gray to silvery blue and emit a resinous odor when crushed. Some trees have a more distinct bluish-white or silvery-white foliage. The cultivated variety ‘glauca’ is noted for this type of coloration
Scotch Pine
Scotch or Scots pine is an introduced species, which has been widely planted for the purpose of producing Christmas trees. It is an extremely hardy species, which is adaptable to a wide variety of soils and sites. As a Christmas tree, it is known for its dark green foliage and stiff branches which are well suited for decorating with both light and heavy ornaments. It has excellent needle retention characteristics and holds up well throughout harvest, shipping and display.
The needles of Scotch pine are produced in bundles of two. They are variable in length, ranging from slightly over 1-inch for some varieties to nearly 3-inches for others. Color is likewise variable with bright green characteristic of a few varieties to dark green to bluish tones more prominent in others. The undersides of Scotch pine needles are characterized by several prominent rows of white appearing stomatal openings.
Eastern White Pine
Beginning with the British colonists, eastern white pine (or white pine) has proven to be one of the most important and most desirable species of North America. It is a truly magnificent tree attaining a height of 80 feet or more at maturity with a diameter of two to three feet. White pine is considered to be the largest pine in the United States. In colonial times, white pines above 24 inches in diameter were reserved for England to be used as ships masts. These trees were identified by blazing a broad arrow on the trunk. Because of the colonists general dislike of British rule, this “broad arrow” policy was one more source of friction between the two. Until about 1890, white pine was considered the species of choice for most commercial uses. It is the state tree of Maine and Michigan.
Fraser Fir
In many respects, Fraser fir and balsam fir are quite similar, although the geographic ranges of the two species do not overlap. Some scientists even suggest that because of the many similarities, the two species were once a single species which has since evolved into the present-day forms.
Fraser fir was named for John Fraser (1750-1811), a Scot botanist who explored the southern Appalachian Mountains in the late 18th century. The species is sometimes called Southern balsam or Southern balsam fir. Locally Fraser fir is known as “She balsam” because of the resin filled blisters on the tree’s trunk. Red spruce, often associated with Fraser fir, is called “He balsam” and lacks the distinctive blisters.
Fraser fir is a uniformly pyramid-shaped tree which reaches a maximum height of about 80 feet and a diameter of 1-1.5 feet. Strong branches are turned slightly upward which gives the tree a compact appearance.
Canaan Fir
Canaan (pronounced “Ka-naan”, with emphasis on the last syllable) is a relative newcomer to the Christmas tree market. It has many similarities to both Fraser and balsam firs in growth and appearance. Unfortunately, this similarity which has led to a great deal of confusion.
In 1909, a variety of balsam fir was described in the literature as having cone scales extending from the bracts. This morphology was a deviation from typical balsam fir cones where the scales are not extended. This variety was then named “phanerolepis” which actually means conspicuous scales. The scientific name of Abies balsamea var. phanerolepis was assigned. The common names most often used were “bracted balsam fir” and “Blue Ridge fir”. Canaan fir had not, at that time, been described separately..
Concolor Fir/White Fir
Concolor Fir/White Fir/White Fir, also commonly called Concolor fir, is native to the western United States and may reach sizes of 130-150 ft. in height and 3 to 4 ft. in diameter. The oldest white firs may occasionally reach 350 years of age. It produces a spire-like crown with a straight trunk.
On older trees, the lower one-half to one-third of the crown is often free of branches.
Leaves (needles) are small and narrow and occur in rows. On upper branches, needles tend to be thicker and more curved than those on lower branches. Needles are usually 1/2 to 1 1/2 inch long, pointed or notched at the tip, bluish-green when young turning dull green with age. Typically, they are flat, without stalks.
All text: Dr. Craig R. McKinley, North Carolina State University