CONIFERS

Gymnosperms, the familiar coniferous, needle-leafed trees, often called evergreens or conifers, make up one of the two great subdivisions of the seed-bearing plants. The other subdivision, Angiosperms, includes the broad-leaved, deciduous tree forms -- the so-called hardwoods. Conifers manifest a striking range of variation in structure, habit, size, and longevity.

The most widespread forests of North America are those of conifers or softwoods, cone-bearing evergreen trees with small leaves shaped liked needles and scales. Within the U.S., main geographic types are the northern coniferous forest, the Pacific Coast coniferous forest, and the Rocky Mountain coniferous forest.

Northern coniferous forests, sometimes called "north woods", range from Alaska and Canada down into the northern U.S. Tree heights vary from 100 feet down to about 20 feet, decreasing northward towards the tundra areas. Eight species compose this forest, white spruce, black spruce, balsam fir, jack pine, tamarack, paper birch, balsam poplar, and quaking aspen.

Along the humid, cool northwest Pacific coast of America, from Alaska down into northern California, is the greatest stand of timber on earth. It is the densest, tallest, most magnificent, and most valuable. Giant evergreens typically grow from 200 to 250 feet high and from 5 to 8 feet in trunk diameter. Some reach over 350 feet high or 30 feet in trunk diameter. Major species include western hemlock, Sitka spruce, Lawson cypress, redwood, Douglas-fir, western white pine, sugar pine, ponderosa pine, and Jeffrey pine.

The Rocky Mountains from Canada south into Mexico have coniferous forests in altitudinal zones. Evergreen trees typically range from 40 to 150 feet in height with trunk diameters from 1 to 4 feet. Lodgepole Pine is common throughout the northern Rockies in dense stands of medium-sized trees on burned areas. At the timberline is the subalpine spruce-fir forest of Englemann Spruce and subalpine fir. Douglas-fir, often with aspens, occupies the next lower zone. Southward, especially into Arizona and New Mexico, are open forests of ponderosa pine. At lower altitudes is the pinyon-juniper woodland, composed of scattered dwarf nut pines called pinyons, and junipers, shrubby rounded trees usually less than 20 feet high.

To a modeler, the six most important parameters of a conifer are size, shape, color, texture, habitat, and range. Size includes the total tree height, the trunk diameter, and even the size of the cones. Shape includes the branching pattern, general foliage outline, and crown configuration. Color includes the trunk, branches, twigs, and cones. Texture includes the bark and foliage. Modelers must also be aware of growth habitats and range to create realistic model trees which are appropriate for the layout and to locate them in appropriate settings

SIZE. Trees are probably the most underscaled item on any model railroad. In S scale, a model of a mature 130 foot ponderosa pine tree should be about 24" high, 4" wide, with a trunk diameter of 3/4" and with cones about 3/32" long. In HO scale, a model of a mature 160 foot sugar pine tree should be about 21" high, 3" wide, with a trunk diameter of 5/8" and cones about 3/16" long.

SHAPE. Conifers come in a wide variety a shapes. Some are tall and cylindrical; others are pyramidal or cone shaped. Crown foliage varies from sharply pointed to flat. Some conifers are light and open; others extremely dense. Trees on slopes and in protected groves are generally symmetrical unless crowded; near the timberline they are windswept and often grotesquely gnarled. Trunks may rise straight up or may be sharply tapered. Some trunks have heavily buttressed or spreading bases. Branching patterns may be flat horizontal, pendulous, or upswept. Patterns may vary widely within the same tree between lower and upper branches. Some conifers are branched to the ground; others show a large expanse of bare trunk between ground level and the lowest branch. Some conifers retain their dead lower branches, called "widow-makers" by hikers. Cones may point up, or may hang down. Some are on uppermost branches only, at branch ends; others dispersed throughout the foliage.

COLOR. Conifer foliage ranges from steely gray-blue, through blue, blue-green, dark green, green, to yellow-green. Needles may be of different colors on upper and lower edges. The individual needles may also have whitish or yellowish stripes, which, from a distance, impart a characteristic hue to the foliage. New growth may be of a different color than the older needles. Cones, which may be cylindrical, egg-shaped, or berry-like, vary from brown, through all shades of reddish-brown and yellow-brown to purple, red, and blue. Trunks, branches, and twigs vary from blackish-brown, through brown, reddish-brown and gray-brown, to gray and whitish-gray.

TEXTURE. Bark texture may be smooth, ridged, deeply furrowed, fibrous, or plated. Foliage texture includes needle-like and scaly types of leaves. Needles may be round, flat, or angular. Foliage texture is also influenced by length of needles, which range from 1/2" to 12". The foliage may be sharp and prickly or soft and pliant.

HABITAT. Conifers grow either in pure stands or mixed forests. In the pure stands, all trees are of the same species and are uniformly sized. Pure stands may be small groves or entire forests encompassing many square miles. Mixed forests include varying species. Some conifers, like those in the Rocky Mountain coniferous forest, reach maturity in less than 100 years. Others, in the Pacific Coast coniferous forests may take 400 - 600 years. Some conifers are over 4,000 years old, such as the sequoias and bristlecone pines. Conifers are greatly influenced by fires; in fact, some species require fires to reproduce. Forests are also dynamic. They go through stages after fires, disease, or clearing; some plant species recover quickly, then give way to others. Modelers should not be too greatly influenced by what a particular prototype scene looks like today; the species there may have changed significantly since the period being modeled.

Each conifer has at least two names, a common name and a scientific name. Common names may vary locally, but the scientific name is used uniformly throughout the world. The scientific name is composed of two parts. The first word, always capitalized, is the Genus; the second word, not capitalized, is the species. The following list of conifers which may be of interest to modelers uses the common name first, in quotation marks, followed by the scientific name in italics.

"SILVER FIR". Abies amabilis. Height: 80’ - 150’. Trunk dia: 2’ - 4’. Foliage: shiny dark green above, silvery-white beneath. Shape: spirelike, conical crown of short, down-curving branches. Bark: light gray, smooth; becoming scaly and reddish-gray or reddish-brown. Cones: cylindrical, upright on topmost twigs; purple; 3" - 6" long. Habitat: coastal fog belt and interior mountain valleys; in coniferous forests. Elev: 1000’ - 6000’. Range: Pacific Coast; Alaska to Oregon and extreme NW California.

"WHITE FIR". Abies concolor. Height: 70’ - 160’. Trunk dia: 1.5’ - 4’. Foliage: light blue-green. Shape: narrow, pointed crown of short, symmetrical, horizontal branches. Bark: light gray, smooth. Cones: cylindrical, upright on topmost twigs; greenish, purple or yellow; 3" - 5" long. Habitat: pure stands; also in mixed fir forests. Elev: 5500’ - 11,000’. Range: SE Idaho southeast to New Mexico, west to California, and north to SW Oregon.

"GRAND FIR". Abies grandis. Height: 100’ - 200’. Trunk dia: 1.5’ - 3.5’. Foliage: shiny dark green above, silvery-white beneath. Shape: narrow, pointed crown of stout, curved, and slightly drooping branches. Bark: brown; smooth, becoming deeply furrowed into narow scaly ridges. Cones: cylindrical, upright on topmost twigs; green or brown; 2" - 4" long. Habitat: valleys and mountain slopes; in coniferous forests. Elev: 0 - 6000’. Range: British Columbia south along coast to California; also south in Rocky Mountains to central Idaho.

"ALPINE FIR". Abies lasiocarpa. Height: 50’ - 100’. Trunk dia: 1’ - 2.5’. Foliage: dark green. Shape: long-pointed, spirelike crown and rows of horizontal branches reaching nearly to base. Bark: gray; smooth. Cones: cylindrical, upright on topmost twigs; dark purple; 2.25" - 4" long. Habitat: spruce-fir forests with Engelmann spruce; also in mixed conifer forests. Elev: 8000’ - 12,000’. Range: Central Yukon and SE Alaska southeast to New Mexico.

"RED FIR". Abies magnifica. Height: 60’ - 120’. Trunk dia: 1’ - 4’. Foliage: blue-green. Shape: open conical crown, rounded at tip; short nearly horizontal branches. Bark: thick, reddish-brown, deeply furrowed into narrow ridges. Cones: cylindrical, upright on topmost twigs; purplish-brown; 6" - 8". Habitat: pure stands and mixed conifer forests. Elev: 6000’ - 9000’. Range: Cascades south to Coast Ranges of California; throughout Sierra Nevada to central California and western Nevada.

"NOBLE FIR". Abies procera. Height: 100’ - 150’. Trunk dia: 2.5’ - 4’. Foliage: blue-green. Shape: conical crown, rounded at tip, short nearly horizontal branches. Bark: gray-brown; smooth, becoming brown to red-brown; furrowed into irregular, long scaly plates. Cones: cylindrical, upright on topmost twigs; green, becoming purplish-brown; 4.5" - 7" long. Habitat: always in mixed conifer forests, never in pure stands. Elev: 3000’ - 7000’. Range: Cascades and Coast Ranges, from Washington south to NW California.

"ENGELMANN SPRUCE". Picea Engelmanni. Height: 80’ - 100’. Trunk dia: 1.5’ - 2.5’. Foliage: dark green or blue-green. Shape: dense, narrow, conical crown of short branches spreading in close rows. Bark: grayish or purplish brown; thin and scaly. Cones: cylindrical, hanging at twig ends; shiny light brown; 1.5" - 2.5" long. Habitat: dominant with subalpine fir; also in mixed conifer forests. Elev: 8000' - 12,000'. Range: British Columbia and Alberta southeast to New Mexico.

"BLUE SPRUCE". Picea pungens. Height: 70' - 100'. Trunk dia: 1.5’ - 3’. Foliage: dull blue-green or bluish. Shape: conical crown; stout horizontal branches in rows. Bark: gray or brown; furrowed and scaly. Cones: cylindrical, hanging; shiny light brown; 2.25" - 4" long. Habitat: narrow bottomlands along streams; often in pure stands. Elev: 6000' - 11,000'. Range: Rocky Mountains from W. Wyoming and E. Idaho south to N. and E. Arizona and S. New Mexico.

"SITKA SPRUCE". Picea sitchensis. Height: 160’. Trunk dia: 3’ - 5’. Foliage: dark green. Shape: straight trunk from butressed base; broad, open, conical crown of horizontal branches. Bark: gray; smooth, becoming dark purplish-brown with scaly plates. Cones: cylindrical, hanging; light orange-brown; 2" - 3.5" long. Habitat: coastal forests in pure stands and with Western Hemlock. Elev: 0 - 3000’. Range: Pacific coast from S. Alaska to NW California.

"BRISTLECONE PINE". Pinus aristata. Height: 20' - 40'. Trunk dia: 1’ - 2.5’. Foliage: dark green. Shape: broad, irregular crown of spreading branches; shrub at timberline. Bark: whitish-gray, smooth; becoming redish brown, furrowed. Cones: cylindrical, hanging; dark purplish-brown; 2.5" - 3.5" long. Habitat: exposed ridges near timberline; often in pure stands. Elev: 7500' - 11,500'. Range: Colorado and N. New Mexico west to E. California.

"LODGEPOLE PINE". Pinus contorta. Height: 20' - 80'. Trunk dia: 1’ - 3’. Foliage: yellow-green to dark green. Shape: tall with narrow, dense, conical crown; or small with broad, rounded crown. Bark: light brown, thin and scaly. Cones: egg-shaped, hanging; shiny yellow-brown; 0.75" - 2" long. Habitat: high mountains; often in pure stands. Elev: 7000' - 11,500'. Range: Alaska south on Pacific coast to N. California; south in Rocky Mountains to S. Colorado; also in Black Hills of South Dakota.

"PINYON". Pinus edulis. Height: 15' - 35'. Trunk dia: 1’ - 2’. Foliage: light green. Shape: bushy; short trunk with compact, rounded, spreading crown. Bark: gray to redish-brown; rough, furrowed. Cones: egg-shaped, hanging; yellow-brown; 1.5" - 2" long. Habitat: open woodlands alone or with junipers; foothills, mesas, plateaus, & lower slopes. Elev: 5000' - 7000'. Range: southern Rocky mountains from Utah and Colorado south to New Mexico and Arizona.

"LIMBER PINE". Pinus flexilis. Height: 40' - 50'. Trunk dia: 2’ - 3’. Foliage: light or dark green. Shape: broad, rounded crown with rows of stout branches; windswept, deformed shrub at timberline. Bark: light gray, smooth; becoming dark brown, furrowed. Cones: egg-shaped, hanging; yellow-brown; 3" - 6" long. Habitat: slopes and ridges to timberline; often in pure stands. Elev: 5000' - 12,000'. Range: Rocky Mountains, from Canada south to N. New Mexico.

"JEFFREY PINE". Pinus jeffreyii. Height: 80’ - 130’. Trunk dia: 2’ - 4’. Foliage: light gray-green or blue-green. Shape: open, conical crown of spreading branches. Bark: purplish-brown; thick, furrowed into narrow scaly plates. Cones: conical or egg-shaped, hanging; light reddish-brown; 5" - 10". Habitat: pure stands and with other conifers. Elev: 6000’ - 9000’. Range: SW Oregon south through Sierra Nevada to W. Nevada and S. California.

"SUGAR PINE". Pinus lambertiana. Height: 100’ - 160’. Trunk dia: 3’ - 6’. Foliage: blue-green. Shape: unbranched for long span; open, conical crown of long, nearly horizontal branches. Bark: brown or gray; furrowed into irregular scaly ridges. Cones: cylindrical, hanging; shiny light brown; 11" - 18". Habitat: mixed conifer forests, not in pure stands. Elev: 2000’ - 7800’ in north; 4000’ - 10,500’ in south. Range: W. Oregon south through Sierra Nevada to S. California.

"WESTERN WHITE PINE". Pinus monticola. Height: 100’. Trunk dia: 3’. Foliage: blue-green. Shape: narrow, open, conical crown of horizontal branches. Bark: gray; thin, becoming furrowed into rectangular, scaly plates. Cones: cylindrical, hanging; yellow-brown; 5" - 9". Habitat: mixed forests; occasionally in pure stands. Elev: 0 - 3500" in north; 6000’ - 9800’ in south. Range: northern Rocky Mountains from Canada southeast to NW Montana; Pacific Coast south through Sierra Nevada to central California.

"PONDEROSA PINE". Pinus ponderosa. Height: 60' - 130'. Trunk dia: 2.5’ - 4’. Foliage: dark green. Shape: broad, open, conical crown of spreading branches. Bark: yellow-brown, irregularly furrowed into large, flat, scaly plates. Cones: conical or egg-shaped, hanging; light reddish-brown; 2" - 6" long. Habitat: pure stands forming extensive forests; also in mixed conifer forests. Elev: 4000' - 9000'. Range: widely distributed; British Columbia east to SW North Dakota, south to Trans-Pecos Texas, west to S. California.

"DOUGLAS-FIR". Pseudotsuga menziesii. Height: 80' - 200'. Trunk dia: 2’ - 5’. Foliage: dark yellow-green or blue-green. Shape: narrow, pointed crown of slightly drooping branches. Bark: reddish-brown, very thick; deeply furrowed into broad ridges. Cones: narrowly egg-shaped, hanging; light brown; 2" - 3.5" long. Habitat: mountain slopes in pure stands; also in mixed conifer forests. Elev: 0 - 2700’ on north coasts; 0 - 6000’ on south coasts; 8000' - 9500' in Rocky Mountains. Range: British Columbia south along Pacific coast to central California; Rocky Mountains to SE Arizona and to Trans-Pecos Texas.

"WESTERN HEMLOCK". Tsuga heterophylla. Height: 100’ - 150’. Trunk dia: 3’ - 4’. Foliage: Shiny dark-green. Shape: long, slender, often fluted trunk; narrow, conical crown of short, slender horizontal or slightly drooping branches. Bark: reddish-brown to gray-brown; deeply furrowed into broad, scaly ridges. Cones: elliptical, hanging down at twig ends; brown; 0.75" - 1". Habitat: dense pure stands and with Sitka Spruce and other conifers. Elev: 0 - 2000’ along coast; 2000’ - 6000’ in mountains. Range: S. Alaska southeast to NW California; Rocky Mountains south to N. Idaho and NW Montana.

"WESTERN REDCEDAR". Thuja plicanta. Height: 100’ - 150’. Trunk dia: 2’ - 8’. Foliage: shiny dark green, usually whitish beneath. Shape: tapered trunk, butressed at base; narrow, conical crown of short, spreading branches, drooping at ends. Bark: reddish-brown; thin, fibrous, shreddy. Cones: elliptical, clustered, upright; brown; 0.5" long. Habitat: widespread forests with western hemlock, also other conifers. Elev: 0 - 3000’ on coast; 4000’ - 7000’ in Rocky mountains. Range: SE Alaska, southeast along coast to NW California; Rocky Mountains to W. Montana.

"INCENSE-CEDAR". Libocedrus decurrens. Height: 60’ - 150’. Trunk dia. 3’ - 5’. Foliage: shiny green. Shape: tapering, irregularly angled trunk; narrow, columnar crown, becoming open and irregular. Bark: light or reddish-brown; thick and deeply furrowed into shreddy ridges. Cones: oblong, hanging down at end of twigs; 0.75" - 1" long. Habitat: mixed conifer forests, seldom in pure stands. Elev: 1200’ - 7000’. Range: W Oregon south to S California and extreme W Nevada.

"REDWOOD". Sequoia sempervirens. Height: 200’ - 325’. Trunk dia: 10’ - 15’. Foliage: dark green above; whitish-green beneath. Shape: much enlarged and butressed base; short, narrow, irregular, open crown with horizontal or drooping branches. Bark: reddish-brown; tough, fibrous; deeply furrowed into broad scaly ridges. Cones: elliptical, hanging down at end of twigs; reddish-brown; 0.5" - 1.125" long. Habitat: terraces in pure stands; also with mixed conifers. Elev: 0 - 3000’. Range: coastal belt, from SW Oregon south to central California.

"PORT-ORFORD-CEDAR". Chamaecyparis lawsoniana. Height: 70’ - 200’. Trunk dia: 2.5’ - 4’. Foliage: dull green above; whitish beneath. Shape: enlarged base; narrow, pointed, spirelike crown; horizontal or drooping branches. Bark: reddish-brown; deeply furrowed into long fibrous ridges. Cones: Round, in clusters; reddish-brown; 0.375" dia. Habitat: with other conifers; sometimes in pure stands. Elev: 0 - 5000’. Range: SW Oregon and NW California in narrow coastal belt; also Mt. Shasta area.

"WESTERN JUNIPER". Juniperus occidentalis. Height: 15’ - 30’. Trunk dia: 1’ typical; sometimes much larger to 16’. Foliage: gray-green. Shape: broad crown of stout, spreading branches; becomming ragged and gnarled with age. Bark: reddish-brown; furrowed; shredded. Cones: short, elliptical, berry-like; blue-black; 0.25" - 0.375" dia. Habitat: slopes and plateaus, common at high altitudes. Elev: 7000’ - 10,000’. Range: central and SE Washington south to S. California; common in Sierra Nevada.

"ROCKY MOUNTAIN JUNIPER". Juniperus scopulorum. Height: 20' - 50'. Trunk dia: 1’ - 1.5’. Foliage: gray-green. Shape: narrow, pointed crown, slender branches. Bark: reddish-brown; thin, fibrous, shreddy. Cones: round, berry-like; bright blue with whitish coat; 0.25" dia. Habitat: rocky outcrops; also in foothills with pinyons. Elev: 5000' - 9000'. Range: central British Columbia east to W. North Dakota, and south to Trans-Pecos Texas.