The Junipers

Classic Western Trees

by Damian Fagan

Western Juniper at Yosemite

Southwest locals often refer to juniper trees as “cedars.” Towns like Cedar City, Utah, Cedaridge, Colorado or Cedar Springs, Nevada reflects this localism. Where this misnomer started is unknown. Probably some early settlers mistakenly were associating the overlapping, scalelike leaves or the shredded-bark-look or the reddish wood of a juniper to that of a cedar. Maybe that or Juniper City, Utah just didn’t have the same ring.

One big difference between the trees is that cedars produce small woody cones and junipers produce a bluish berrylike cone.

Junipers are to the Southwest what fir trees are to the Northwest: widespread and represented by several species. But junipers define the landscape with their glacial growth, half-dead/half-alive appearance and fragrant aroma. Though often maligned due to their invasion of grasslands, junipers provide food and resources for a variety of wildlife. Birds and mammals consume the seeds and vegetation, and the trees are used for nest sites or dens for rodents. People, too, have benefited from junipers for hundreds of years, using the trees for food, fuel and fenceposts.

Junipers occur from sea level to 10,000 in elevation across the West. In the Southwest, they are common on the mesa tops and ridges, often found in association with the pinyon pine. Though they may grow in pure stands, the trees are spaced apart because of their shade intolerance. The trees become established in overgrazed lands due to the lack of competition and dispersal of their seeds by wildlife.

Utah Juniper and berries.

Utah juniper and berries

Junipers bear both male and female cones, although the female cones are often referred to as “berries.” Most junipers are dioecious, meaning male and female cones are found on separate trees. Some trees may bear both types of cones.

The smaller male cones produce pollen sacs that release pollen grains in spring and summer. Hayfever sufferers will attest to this as the wind-borne pollen aggravates their allergies. The female cones have succulent and fleshy scales called sporophylls, and these scales fuse together after pollination. Enclosing the hard seed coat, the cones take one to three years to ripen depending upon the species. The cones or “berries” range from bluish to purplish-black or red and have a smooth, whitish “bloom” that gives them the appearance of a polished blueberry. Certain birds and mammals find these seeds edible; their stomach acids corrode the fleshy coating and hard seed coat, but the seeds pass through the system.

Utah Juniper in the winter.

Utah juniper in the winter

Of the sixty species of junipers worldwide, about fifteen species grow in North America. Their growth habit may be sprawling, low shrubs or upright trees; their growth depends upon the species and environment where they grow. Slow growing, mature trees are easily hundreds of years old.

Another desert attribute of the tree is that junipers can inhabit poor quality soils and thrive where others fail. At times they are a pioneer species, able to become established in altered landscapes. Of course, these plants will also take advantage of fertile and moist sites and may be found growing in canyon bottoms or sheltered sites.

To exist in these dry climates, juniper trees have stout taproots and for some species extensive lateral root systems that efficiently obtain moisture where none seems to exist. Junipers are also dimorphic, meaning they have two growth forms. Seedlings bear bluish-green awl-shaped leaves that are pointed at the tip possibly to discourage herbivores. Mature leaves are darker green and scalelike in appearance. This juvenile form may help reduce herbivores from devouring the young plants. The mature leaves are borne in pairs or whorls of three, are rounded at the tip and appressed to the twig. As the trees age, the trunks may become twisted or gnarled. Exactly why this habit occurs, no one knows. Stout single trunks or multiple stems originating from the ground are a couple of forms the trees exhibit.

Junipers are members of the cypress family (Cupressaceae) which includes cedars. The genus Juniperus is the old Latin name for the plant.

Occidentalis means “western” and indicates the range of this species. Western junipers occur in the Great Basin portion of eastern California, northwestern Nevada, eastern Oregon, and portions of eastern Washington and southwestern Idaho. In the Sierras, these junipers often grow at higher elevation, 7,000 to 10,000 feet, and resemble small sequoias. The trees occupy rocky habitats where other conifers cannot gain a roothold.

Long lived, western junipers may easily reach 800 to 1,000 years old. “Bennett Juniper” of Deadman Creek, California is over 85 feet tall and sports a 14-foot diameter. This tree is estimated to be somewhere between 3,000 and 6,000 years old. Longevity is a verb for these trees.

The small scalelike leaves are 1/16 to 1/8 inch long and have a white resinous spot on the leaf’s upper surface. Bearing two to three seeds, the ¼ inch diameter cones take two years to mature. Sometimes western juniper fruits are fed to chickens to produce gin-flavored eggs.

As western junipers mature, the reddish bark becomes thicker and stringier. Similar to other junipers, western junipers do not attain a great height, but may average 40 feet tall. Trunks on older trees average 2 to 4 feet wide, but specimens up to 13 feet in diameter have been recorded.

Utah Juniper in Dead Horse State Park

Utah juniper in Dead Horse State Park

Utah Juniper (Juniperus utahensis)

The type specimen of this tree was collected in Utah, hence, its common name and species name, utahensis. A very common tree in the Southwest and Great Basin, Utah junipers may cover more acres within these regions than any other tree species. Together with the pinyon pine they are the dominant trees of the pinyon-juniper woodlands or PJ forests of the Southwest. Generally occurring between 3,000 and 8,000 feet in elevation, these trees were widely used by the Ancestral Puebloans and tribes of the Great Basin for firewood, building material and as a food and medicinal source.

Leaves and berries were collected and brewed to make herbal teas to treat colds, headaches, joint pain, stomach aches and other ailments. The berries were eaten only as a last resort. The fibrous bark could become padding for craddleboards, woven into sandals or clothing, plaited into cordage, or substituted for tobacco. Even the hard seed shells discarded by chipmunks or ground squirrels provided a source of beads that were strung together or sewn onto clothing. Junipers also provided a source of roof poles or headers for pueblo construction.

The arrangement of the leaves in a circular pattern gives the twigs a resemblance to coral. Although Utah junipers have various growth forms, they generally grow less than 40 feet tall.

Porcupine asleep in a juniper.

Porcupine asleep in a juniper

Rocky Mountain Juniper (Juniperus scopulorum)

Growing throughout the Rocky Mountains from New Mexico up through Canada (thus the common name), these junipers mix with Utah juniper where their two ranges overlap. Often found growing at the upper end of the pinyon-juniper belt, Rocky Mountain junipers mix with ponderosa pine, Douglas fir and white fir at higher elevations and more northern latitudes. This species even grows on islands in the Northwest’s Puget Sound.

One Rocky Mountain juniper in northeastern Utah, the “Jardine Juniper” of Logan Canyon, suffers from “age discrepancy.” Locals claim the tree to be twice the reported 1,500 years old. Over six feet in diameter, the tree isn’t telling its age.

The small, overlapping scalelike leaves are borne in two pairs along a stem, thus giving the twigs a square appearance. The leaves lack any resinous dots on their surface and the overall appearance of the foliage is best described as “lacy.”

The smaller berry size is another feature to distinguish the Rocky Mountain juniper from the Utah juniper: 1/8 inch versus 1/4 inch in diameter. Waxwings, American robins and Townsend’s solitaires are three bird species that consume the seeds, then disperse them in their droppings. Passage through the digestive tract probably helps dissolve the seedcoat and influences germination. Tree climbing gray foxes may also consume the seeds, the evidence of their diet being revealed in their scat, as well.

The species name scopulorum refers to the plant's habit of growing in rocky places.

Alligator Juniper (Juniperus deppeana)

Named after their reptilianlike bark, the alligator juniper is also known as the checkered-bark or oakbark juniper. The deeply fissured bark becomes divided into small squares with age.

Growing in oak and pinyon-juniper woodlands in Arizona, New Mexico and Texas and into Mexico, these trees grow at elevations between 4,500 and 8,000 feet. The trees may produce multiple stems from a stump, and a single-trunked specimen might reach 65 feet tall.

Cones of the alligator juniper are 1/2 inch in diameter and are a waxy-gray color. They usually contain four seeds, which mature in their second year.

The species name deppeana honors Ferdinand Deppe (1794-1861), a German naturalist and painter who collected plants in Mexico, California and Hawaii for the Berlin Museum. The tree was first collected in the Zuni Mountains of northwestern New Mexico back in 1851 by Dr. Samuel Washington Woodhouse (1821-1904), the surgeon/naturalist on the Sitgreaves Expedition to the Colorado and Zuni rivers.

Oneseed Juniper (Juniperus monosperma)

Oneseed junipers are mostly that – the cones bear one seed, although sometimes two seeds are present. This species occurs throughout New Mexico and portions of Arizona, Colorado, Texas and Oklahoma. Its similarity with Pinchot juniper in Mexico makes differentiating the two species difficult.

Growing between 3,000 and 6,900 feet in elevation, this juniper has a multi-stemmed growth habit resulting in a dense, rounded appearance. The many-stemmed trunks create a shorter tree; often these trees are less than 20 feet tall. Their grayish-brown bark splits into long strips with age, and they produce bluish or pinkish-purple cones.

During droughts, oneseed junipers may halt their active growing, then resume growing once there is sufficient moisture. A record oneseeded specimen growing in Arizona had a 130-inch circumference and reached 28 feet tall. The species name monosperma means “one seed” and refers to the single seed borne in the cone.

Though it is impressive to see massive examples of these trees, the partially alive ones with twisted trunks or polished wood growing out of slim fractures in sandstone provide the most classic profile of these desert trees.

References
Sam Benvie, The Encyclopedia of North American Trees, Firefly Books, Buffalo, New York, 2002.

Ronald M. Lanner, Trees of the Great Basin: A natural history, University of Nevada Press, Reno, Nevada, 1984.

Maggie Stuckey, Western Trees: A field guide, Falcon Press Publishing, Helena, Montana, 1998.

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