Forestry/Tree List

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The 2012 Official Tree List may be found here.

Introduction to Ginkgoaceae (Ginkgos)

The Ginkgo is a living fossil and one of the most unusual trees in the world. The genus is known from fossils that date back 270 million years and are nearly identical to present-day trees. The Ginkgo is classified not only in its own family, but in a separate division of the kingdom Plantae. The fruit produced by female Ginkgo trees is technically a naked seed with a fleshy outer coat like a yew. Extracts of Ginkgo leaves have long been used medicinally, and some modern studies suggest that they may have a few potentially beneficial effects, such as improving blood flow. The wood of ginkgos has never been used commercially, but the seeds are a popular specialty food item in asia. The species is important as an ornamental tree with very high tolerance for the confined spaces and pollution of cities.

Ginkgo biloba (Ginkgo)

Ginkgo is a unique gymnosperm in the monotypic family Ginkgoaceae. It is also classified in it's own division of Plantae, Ginkgophyta, as opposed to Pinophyta or Magnoliophyta. It is a well known example of a living fossil, although several other species in the Ginkgo genus have also been found in the fossil record. Ginkgo fossils first appeared in the Early Jurassic and became widespread throughout Laurasia, but they disappeared at the end of the Pliocene (about 2 mya) except for in a small area of central China. Today they are widely cultivated around the world, although they are classified as endangered by the IUCN due to their small natural range.

Ginkgos are large trees with somewhat erratic branches and a very long life span. The leaves are very distinctive, being fan-shaped with veins radiating from the base and constantly dividing in two (dichotomous venation). Gingko Leaves

Introduction to Taxaceae (Yews)

The leaves, bark, and seeds of some yews are poisonous, but the fleshy red fruit covering the seed is not. Birds consume and disperse the seeds in dropings.

Taxus brevifolia (Pacific Yew)

The Pacific Yew is a conifer native to the Pacific Northwest of North America. It is easily distinguished by it's modified cones, which resemble bright red berries. These are not berries; they are called arils and are a a modified scale of a seed cone, analogous to the cones of pines. They begin as a green band around the base of the seed and develop into the fleshy red "false-fruit". The leaves are green, flat, and lanceolate. They are arranged spirally on the stem but appear to be in two flat rows due to a twist in the leaf base.

It is also called western yew. Pacific yew tolerates shade, and in undisturbed stands is usually found as an understory tree. Growth of such trees is slow, but where the overstory has been removed or thinned, diameter growth on undamaged yew trees may increase considerably. Pacific yew rarely exceeds 60 cm (24 in) in d.b.h., and 15 m (49 ft) in height. The largest on record is 142 cm (56 in) in d.b.h., and 18 m (60 ft) in height (28). The wood is hard, heavy, and resistant to decay. Although not of great interest to the forest products industry, it has many special uses. The bark of Pacific yew contains a drug, taxol, that is being used in cancer research, so demand for yew bark by the National Cancer Institute has increased dramatically in recent years (9). Pacific Yew Leaves

Pinaceae

Intro to Abies (Firs)

The genus Abies contains the true firs, and includes 48-55 species worldwide and 11 native to North America. Firs are characterized by short, soft, and blunt needles. Cones are upright on the twig and can range from 2 inches to 7 inches in the case of the California Red Fir (A. magnifica). The leaves are curved up on branches with cones; these usually occur high up on the tree. During the fall, cone scales fall off individually, leaving only a central spike. Drops of white resin can often be found on mature cones.

Abies balsamea (Balsam Fir)

The Balsam Fir is a tree native to the Northeast US and much of Northeast and Central Canada.

It is a small to medium-size evergreen tree typically 14–20 metres (46–66 ft) tall, rarely to 27 metres (89 ft) tall, with a narrow conic crown. The bark on young trees is smooth, grey, and with resin blisters (which tend to spray when ruptured), becoming rough and fissured or scaly on old trees. The leaves are flat needle-like, 15 to 30 millimetres (½–1 in) long, dark green above often with a small patch of stomata near the tip, and two white stomatal bands below, and a slightly notched tip. They are arranged spirally on the shoot, but with the leaf bases twisted to appear in two more-or-less horizontal rows. The cones are erect, 40 to 80 millimetres (1½–3 in) long, dark purple, ripening brown and disintegrating to release the winged seeds in September. Balsam Fir Needles

Abies concolor (White Fir)

The White Fir is native to the mountainous regions of the southwest US, and its wood is generally undesirable due to its poor wood quality, softness, and knots. There are two subspecies, and it is closely related to the Grand Fir.

It is a large forest tree from 60 to 200 feet in height that can live up to 300 years or more. Its leaves or needles are 2 to 3 inches long, silvery-blue to silvery-green, extending at nearly right angles from all sides of the twig; the needles are flattened, stomatiferous above and below, rounded or acute at the apex. The upright cones are 2 to 5 inches long, oblong, olive-green to purple; bracts shorter than the scales, with short, broad erose shoulders, and spikelike tips. The bark is 4 to 7 inches thick on old trunks, ashy gray and divided by deep irregular furrows in thick, horny flattened ridges; young stems with conspicuous resin blisters. White Fir Needles

Abies grandis (Grand Fir)

The Grand Fir is native to the northwest regions, mainly in Washington. Often used as an ornamental tree due to its scent, it is used for only cheap constructions. Identifiable by its flat needle growth pattern. The tree is also used as lumber, pulp, and the leaves and bark were used by Native peoples for dyes, medicines, air fresheners, religious regalia, and basketry. The resin from it's blisters have a variety of uses. (ex. a sealant for wood exposed to water.)

It is a rapid-growing tree that reaches its largest size in the rain forest of the Olympic Peninsula of Washington. One tree in that area measures 200 cm (78.9 in) in d.b.h., 70.4 m (231 ft) tall, and has a crown spread of 14 m (46 ft). The species also has historic significance. The famous Barlow Road snub-trees on the south side of Mount Hood in Oregon were grand firs. They were used by early settlers to control the rate of descent of their covered wagons on a particularly steep slope in their trek from east to west. Some of the rope-burned trees are still standing after 150 years. Grand Fir Needles

Abies lasiocarpa (Subalpine Fir)

While this tree is restricted to spotty areas of the northwest US, it is heavily prominent in Canada. Grows to a medium size and is used in paper manufacture. This tree has a blue shade, with cone up to 12 cm. The needles are arranged in a vertical, flat pattern, but with twisted petioles. The bark is generally smooth but becomes scaly as the tree matures. While no official subspecies, there are three taxa. The tree shape is tapering, and becomes very thin near the top of the tree, growing many times taller than wide, giving it a slender and spire-like look. The upper several feet of the crown may have a diameter of less than 1 foot. The branches of this tree persist on the trunk right to the ground. This tree seldom exceeds 90 feet in height and 2 feet in diameter at maturity.

The leaves are needle-like, and about 1 inch long. The tips of the leaves are blunt and the leaf itself is flattened and flexible. Even though the leaves arise from twigs on all sides (spirally arranged), they all tend to grow upward. Buds are about ¼ inch long and orange colored.

The twigs are usually smooth with small, inconspicuous leaf scars. Young growth twigs are covered with fine hairs. The bark is thin, smooth, and ash-gray colored on young trees. It becomes somewhat furrowed on older trunks. Small resin blisters are abundant on young to medium age trees. The wood is soft and rather brittle, usually light in color and very quick to decay. Subalpine Fir Subalpine Fir Needles and Cones

Introduction to Larix (Larches)

The larches are ten species of tall slender trees. Larches are the only deciduous members of the pine family, losing their needles each winter. Needles are short and soft, growing singly along new growth, but clustered together, tuft-like on short spur twigs along older growth. Cones are small and held upright along branchlets. They mature in a single growing season and persist several years. Pale green in spring and yellow in fall, larches make attractive landscape trees. Larches are fast-growing, but little-used commercially. With a high resin content, the hard and heavy wood is decay resistant and useful for railroad ties, utility poles, flooring, and cabinetry, but is unsuitable for pulp.

Larix laricina (Tamarack)

Tamarack, also known as Larch, is one of two conifers on the National List to be deciduous. The needles are characterized as radiating in clusters from the branches. The cones are similar to hemlocks but stand upright.

It commonly grows in swamps and sphagnum bogs but also grows in upland soils. The flaky dark reddish-gray bark of the tamarack tree resembles Black Spruce.It is easily found in boreal forest bogs, ranges from the Canadian Atlantic Provinces and the Northeast to Alaska. The pale green needles are soft and short (about an inch long) and grow in brush-like tufts on small knobby spurs along each twig. The cones of the tamarack are also fairly small - round, and less than an inch long. Very often you will see the tall tamarack trees growing in pure stands. Just before the needles drop in autumn, the needles turn a beautiful golden color, affording the stands of tamarack a striking contrast to the fall foliage.

Tamarack trees are well adapted to the cold. The tree's natural range is from Labrador to West Virginia, northern Illinois and New Jersey, across southern Canada to Northern British Columbia Alaska. It grows near sea level in northern regions, and at higher elevations in the southern extreme of it’s range. Tamarack Needles

Larix occidentalis (Western Larch)

The Western Larch is extremely similar to an American Larch, and cones are needed to confidentally tell the two apart. The needles on Western Larch are slightly longer than those of Tamarack, and the cones have bracts projecting.

Introduction to Picea (Spruce)

Spruces differ from all other conifers in having a single, pointed, and usually prickly needles that leave a raised leaf scar on the twig when they fall. Spruce cones hang down from the branches, have relatively thin papery scales, and trees usually have a narrow conical form. Spruce wood is a very important source of lumber for construction and for more specialized uses, such as piano sounding boards, and is used extensively for paper pulp.

Spruce needles are typically not flattened (with the exception of some like the Sitka) and are described as 4-angled (meaning the cross-section of the needles is 4-angled).

Picea engelmannii (Engelmann Spruce)

Also known as the Engelmann Blue Spruce and Rocky Mountain White Spruce. It is named after the German-American botanist George Engelmann.

It often hybridizes with White Spruce in the North and Blue Spruce in the South.

It can be differentiated from other spruces by its stout twigs and rather large cones with toothed scales. Other resources state that its twigs have fine hairs on it.

Engelmann Spruce is commonly afflicted by the spruce beetle.

Picea glauca (White Spruce)

Also known as the Skunk or Cat Spruce because of its disagreeable odor when its needles are crushed.

Commonly distinguished by hairless, slender twigs and medium sized cones that are broad and flat-tipped.

Picea mariana (Black Spruce)

Also known as Double, Swamp and Gum Spruce. The smallest spruce and often slender with an irregular crown.

It is commonly distinguished by its small 1" cones, very small needles and slender, hairy twigs.

Difficult to distinguish from Red Spruce.

Introduction to Pinus (Pine)

Pines are distinguished from other genera in the pine family by having relatively long needles in bundles or clusters of two to five and joined at the base, and woody cones with scales thickened at the tip. Needles persist from to to thirty or more years, after which they turn brown and fall in the late summer. All pines produce cones. Cones of most species mature at the end of their second growing season (some species require three growing seasons to mature). All other trees in the pine family have cones that mature in a single growing season. The familiar pine cone is typically egg-shaped, with many woody scales arranged in a spiral pattern, and each scale protects two seeds. As in other gymnosperms, pines do not have true flowers. Pollen is produced in small male cones appearing at the base of new growth in spring. They may be purple, pink, red, orange, or greenish, but all turn yellow as they release pollen and then pale orange and brown as they dry, falling soon after. Female cones with developing seeds are small and scaly, usually near the tips of new growth in the spring. They are varied colors, as in the male cones, but all become green or purple as the cones grown, and eventually turn brown when fully mature, and grayish several years after maturity. There is variation within each species, but differences in color can still be used for identification, as long as cones of similar age are being compared. As many other trees, pines produce large crops of fruit at regular intervals, often about every three to seven years. This is thought to be a strategy to reduce seed predation by squirrels, birds, and other animals. When the trees produce a much larger crop of seeds, that supply exceeds the demand, increasing the chances that seeds will be left uneaten and have a chance to germinate. Cones may fall quickly after maturity, or persist for many years. In a few species, cones persist so long that they are enveloped by the growing trunk. Several species have serotinous cones–they open only when heated by fire. This characteristic is more common in some regions, and varies between individual trees of the same species, so one tree might have its branches festooned with old cones, while a neighboring tree of the same species might have cones that release seeds and fall soon after maturity. The genus Pinus is seperated broadly into the white pine and yellow pine group, differing in many ways. In economic value, pines rank among the most important groups of trees,. They are harvested from the wild and grown commercially worldwide for lumber and for pulp. Pine sap also provides turpentine, and was formerly an important source of pitch and resin, but similar products are now derived from petroleum. Pines are a dominant plant in a variety of ecosystems across north america, and many other species of plants and animals depend on pines for food and shelter.

Introduction to Aceraceae (Maples)

All maples have palmately compound leaves, usually with three or five lobes and long stalks. Maple flowers are small and clustered, but can be quite showy as most species flower before the leaves in spring while the twigs are still bare. Fruit is the familiar maple key of paired seeds with papery wings. The wings cause the fruit to spin rapidly in the air, falling more slowly with the potential to be dispersed on the wind. Maples can be subdivided into many smaller groups of related species based on their flowers. Maples are known for their brilliant fall colors. The leaves of most species turn clear bright red or yellow in the fall, and it is the maples, more than any other group of trees, that are responsible for the celebrated fall foliage. Maple wood is very hard and is used where extreme durability is needed, such as flooring, butcherblocks, and some specialty products such as bowling pins. The wood of maples also has excellent sound-conducting properties, and is used for drums and many stringed instruments. One of the most unusual commercial uses of the maples is for the production of maple syrup. Most maples are trees of mature forests in moist temperate zones, either as large canopy trees or smaller understory trees.

Acer

Acer negundo (Boxelder)

This species is a small to medium-sized tree with a short trunk and a broad, rounded crown of light green foliage. It lives in wet or moist soils along stream banks and in valleys with various hardwoods. It is also naturalized to waste places and roadsides. The leaves are opposite, as in every maple, and are pinnately compound. It has 3-7 irregularly shaped leaflets and is dieocious, with male and female parts on different trees. The leaves turn yellow or red in autumn. The bark is light gray-brown with many narrow ridges and fissures It is found in the breadth of the United States. Boxelder is classed with maples having similar paired key fruits, but is easily distinguished by the pinnately compound leaves. Hardy and fast-growing, it is planted for shade and shelterbelts but is short-lived and easily broken in storms. Plains Indians made sugar from the sap. The common name indicates the resemblance of the foliage of that to elders and the whitish wood to that of box.

Acer rubrum (Red Maple)

This maple is distinguished from other maples by the presence of three serrated lobes. The samara are slightly divergent. Acer rubrum is native to the Eastern United States from Florida to Southern Canada. Often found in swamps.

Acer saccharinum (Silver Maple)

This maple is often distinguished by five deep and serrated lobes. The term Silver comes from the underside of the leaf, which are usually a brilliant white. Note however, that Red Maple can also be silver underneath. This species also has the largest samara of the native maples.

Acer saccharum (Sugar Maple)

This tree is used to make maple syrup. It is the state tree of Vermont. This species has lobes that are deeper than red maples, but not as deep as Silver Maples. The leaf tips often have an overall rounded appearance. The samara are unusual in that the wings turn brown while seeds are green.