Common Trees of Alaska - US Forest Service

1 Common Trees of Alaska United States Prepared by Alaska Region Department of Forest Service R10-XX-XXX. Agriculture August 2009. Western hemlock Tsuga heterophylla Mountain hemlock Tsuga mertensiana Needles Needles Light- to medium- green on top, with two whit- Dark green , white lines on both surfaces, more- ish parallel lines beneath, needles are unequal or-less equal in length, 1/2 to 1 inch long;. in length from 1/4 to 7/8 inch long; Soft and growing from all sides of the branch in Blunt-tipped, soft, shiny, and flat, generally a bottle brush pattern. growing from two sides of branch parallel to Cones the ground. Purplish when young, brown when mature;. Cones Cylindrical, 1 to 2-1/2 inches long;. Brown, oval-shaped, 5/8 to 1 inch long; Thin, papery scales. Thin, papery scales. Bark Bark Divided into narrow flattened ridges, becoming Reddish-brown when young, turning gray- thick and deeply furrowed with age;. brown; Gray when young, turning reddish brown with Scaly when young, becoming thick and fur- age.

2 Rowed with age. Size at maturity and life span Size at maturity and life span 50 to 100 feet in height and 10 to 30 inches in 100 to 150 feet in height and 2 to 4 feet in diameter, can be prostrate in alpine;. diameter; Slow-growing Trees , size 18 to 20 inches in 200 to 500 years. diameter at 180 260 years;. Habitat and distribution 400 to 500 years Sea level to subalpine areas; Habitat and distribution Along Coast Range in central California to the Sea level to 3,500 feet elevation;. Kenai Peninsula of Alaska . From crest of the Sierra-Nevada in California to the Kenai Peninsula in Alaska . Mountain hemlock Tsuga mertensiana Western hemlock Tsuga heterophylla Alaska yellow-cedar Western redcedar Thuja plicata Cupressus nootkatensis Needles Needles Scalelike shiny yellow- green . 1/16 to 1/8 inch Scalelike, overlapping, sharp pointed, 1/16 to long;. 1/8 inch long; Springy, fan-shaped sprays of branches, turning Yellow- green to deep green ; up at ends.

3 Top and bottom of branch sprays similar, with- Branch sprays flat and symmetrical, bottom out apparent white stomate markings. side with white stomate markings. Cones Cones Spherical about 1/2 inch in diameter; Brown, oval-shaped, 1/2 inch long;. green , maturing to brown in 2 years; Clustered near end of branches;. Made of 4-6 shield -shaped scales, sharp cen- Cone scales overlap, woody, and curve out- tral point on each scale, scales do not overlap. ward at maturity. Bark Bark Shredding, grayish brown. Fibrous and stringy;. Cinnamon-red when young, becoming gray Size at maturity and life span with age. Slow-growing Trees ;. 40 to 100 feet tall, and 1 to 2 feet in diameter; Size at maturity and life span Shrub-sized and contorted in bogs and at tree 70 to 100 feet in height in Southeast Alaska line; (growing much taller in southern part of range). Lives up to 1,500 years. and 2 to 4 feet in diameter (occasionally reach- ing 6 feet);. Habitat and distribution 300 to 700 years (occasionally 1,000).

4 Wetland and subalpine forests;. Sea level to tree line; Habitat and distribution From Oregon north along coast through Prince Coastal forests;. William Sound, Alaska . Sea level to 500 feet in elevation;. From northwestern California to Southeast Alaska just south of Frederick Sound. Alaska yellow-cedar Cupressus nootkatensis Western redcedar Thuja pilcata Sitka Spruce Picea sitchensis White spruce Picea glauca Alaska 's state tree Needles Needles 3/4 to 1 inch long, blue- green , four-angled Dark blue- green , squarish, 5/8 to 1 inch long; with whitish lines on all sides;. Needles sharp, growing on all sides of branch- Rigid, pointed, but not sharp to the touch;. es from woody pegs, a character Common to Usually crowded on upper side of the branch. spruce. Cones Cones 1-1/2 to 2-1/2 inches long, light brown;. Light orange-brown, 2 to 3-1/2 inches long; Narrowly oblong, nearly stalkless, hanging Usually found in the top quarter of tree , hang- down.

5 Ing down from branches; Scales thin and flexible with smooth margins. Papery scales. Bark Bark Thin, scaly to smooth;. Thin and smooth when young, developing Gray-brown, with white inner bark. scaly plates with age; Size at maturity and life span Gray, becoming dark purplish brown with age. 40 to 70 feet tall, 6 to 18 inches in diameter;. Size at maturity and life span Reaches 80 to 115 feet tall, 30 inches in diam- 150 to 225 feet in height and 5 to 8 feet in eter;. diameter; tree crown, narrow or spire-like;. Grows to larger size in southern part of its Can live an age of 250 to 300 years. range; Habitat and distribution 500 to 700 years. From sea level to tree line on a wide variety of Habitat and distribution habitats;. Well-drained, upland and riparian forests; Throughout southcentral and interior Alaska Sea level to tree line; east through Canada to Atlantic Ocean, from From northern California, northwest along the the northern tree line south to the Great Lakes.

6 Coastline to the Alaska Peninsula. White spruce hybridizes with Sitka spruce where their ranges overlap, forming Lutz spruce, Picea xlutzii. It shows characteristics intermediate between the two parent Trees . Sitka Spruce Picea sitchensis White spruce Picea glauca Black spruce Picea mariana Shore pine Pinus contorta var. contorta Needles Needles 1/2 inch long, light blue- green , four-angled 1 to 2-1/4 inches long;. with whitish lines on all sides; Two half-round needles in a bundle together Blunt-pointed; making a cylinder when pressed together. Current year twigs with short red or brown Cones hairs. Light brown, egg-shaped, 1-1/4 to 2 inches Cones long;. 1 inch long, rounded and dark; Woody, stiff prickles at the tip of each cone Scales rigid and brittle, margins rounded to scale;. toothed; Pointed backwards on branches. Stay on for several years, hang on short stalks. Bark Bark Dark brown to blackish;. Thin, gray to blackish, becoming flaky with Resinous and scaly, becoming furrowed with age; age.

7 Inner bark is yellow. Size at maturity and life span Size at maturity and life span Shrub-sized and contorted in bogs;. 15 to 30 feet tall and 3 to 6 inches in diameter, Often a scrubby tree , 20 to 40 feet tall and 8 to larger in ideal situations; 12 inches in diameter;. Can reach 250 years in age. To 75 feet tall and 18 to 32 inches in diameter Habitat and distribution on well-drained, sunny sites;. Wet and cold sites on flats or north-facing Lives 200 to 600 years. slopes, also in bogs; Habitat and distribution Usually at lower elevations; Abundant in and adjacent to bogs;. Throughout southcentral and interior Alaska Sea level to subalpine;. east through Canada to Alaska Ocean, from the From northern California to Yakutat, Alaska . northern tree line south to the Great Lakes. Shore pine Pinus contorta var. contorta Black spruce Picea mariana Mary Stensvold Tamarack Larix laricina Paper birch Betula neoalaskana (for- Needles merly B. papyrifera var.)

8 Humilis). Deciduous, soft, flexible, 1 inch long; Leaves In clusters of 10 to 20 on short spur branches; 1-1/2 to 3 inches long, 1 to 2 inches wide;. Blue- green needles turn golden yellow and are Broadly oval with long-pointed tip;. shed in the fall. Margins coarsely double-toothed;. Cones Yellow- green , paler yellowish- green under- 1/2 inch long, dark brown; neath;. With about 20 rounded, finely toothed scales; Twigs with dense covering of resin dots. Held upright on short stalks from horizontal Fruit twigs. Nutlets borne in short, greenish-brown, dry, 1. Bark to 1-1/4 inch-long catkins;. Young Trees with dark gray, smooth, thin; Nutlets tiny, with wings broader than the body. With age becomes reddish brown, scaly, ex- Bark posing darker inner layer. Red-brown on young trunks;. Size at maturity and life span Lightens with age;. 30 to 60 feet tall, 4 to 16 inches in diameter; Smooth, thin, paper-like and peeling. 100 to 200 years. Size at maturity Habitat and distribution To 80 feet tall, 4 to 24 inches in diameter.

9 Bogs, moist places, and along river drainages; Habitat and distribution From the northern slopes of the Alaska Range Common in a variety of habitats, often in to the southern slopes of the Brooks Range, mixed forests with black and white spruce;. east across Canada to Atlantic Ocean, from the From interior Alaska across northern North northern tree line south to the Great Lakes. America to the southwest side of Hudson Bay. Kenai birch (Betula kenaica) is nearly identical to paper birch except for slightly smaller size, leaves, and fewer resin dots on twigs. This tree is endemic to Alaska . Paper birch Betula neoalaskana Tamarack Larix laricina Balsam poplar Populus balsamifera Quaking Aspen Populus tremuloides subsp. balsamifera Leaves Leaves 1 to 31/2 inches long;. 3 to 6 inches long, 2 to 4 inches wide; Nearly round, pointed at tip and rounded at Broad at base, narrowing to a point at the tip; base, edged with many small rounded teeth;. Dark shiny green above, rust-colored under- Shiny green , pale underneath.

10 Neath; Leaf stalks flat, allowing leaves to tremble in Swelling leaf buds are sweetly aromatic in the the slightest breeze. spring. Fruit Fruit Capsules on 3 to 4 inch-long catkins;. 2-parted capsules on 6 inch-long catkins con- Capsules contain numerous tiny cottony seeds. tain numerous tiny cottony seeds. Bark Bark Smooth, greenish white;. Young stems greenish to reddish brown; Important wildlife food. With age becomes thick and deeply furrowed. Size at maturity and life span Size at maturity and life span 20 to 40 feet tall, 3 to 12 inches in diameter;. 80 to 100 feet tall, to 3 feet in diameter; 80 to 100 years average, 200 years maximum. 100 to 200 years. Habitat and distribution Habitat and distribution South-facing slopes and well drained benches;. River valleys and flood plains, alluvial fans, Propagates from root sprouting after distur- glacial outwash areas, lake shores; bance;. A shade-intolerant pioneer species; Throughout interior and southcentral Alaska , From interior Alaska across northern portions across Canada and south to New Mexico.