This observation suggested that perhaps other abiotic factors, damaging insects, or diseases might be contributing to, or were primarily responsible for, the juniper decline. A retired science educator from Blanding, Shumway was the first to document a troubling die-off of the hardy tree species and is now helping federal scientists determine what is killing the junipers.
The die-off was documented last year by Kay Shumway, a retired science educator and botanist from Blanding who first noticed the junipers turning yellow on the southern end of Cedar Mesa. Widespread juniper mortality would deliver an ecological blow similar to what Utah has experienced where bark beetles have run amok in national forests. Those trees look like they were eaten alive, their bark dripping with pitch produced by the trees in a failed effort to repel the attackers.
The afflicted junipers, by contrast, show only modest levels of infestation. Although some juniper had died, many symptomatic trees had healthy, green sprigs of foliage growing from their lowermost branches," the report said.
The report recommends continued monitoring and asked the Forest Service to complete an aerial survey this summer to "assess the extent and severity of the juniper decline and crown dieback" across the Four Corners region.
Twice the Forest Service scheduled such surveys, and both times they were canceled due to inclement weather, according to John Guyon of the Forest Health Protection program based in Ogden. Mapping the juniper mortality is crucial for understanding the extent of the problem and detecting patterns that could bring the causes into sharper focus. This wood is very durable, especially the heartwood. Utah juniper is common on dry plains, plateaus, and the lower elevation of the mountains of the state.
Its elevation ranges between 4, and 7, feet. It is common in elevations below pinyon pine, and above the sagebrush-grass zone.
Across the West, junipers have expanded their historical range in the years since European settlement, especially into sagebrush-grass communities below areas of traditional pinyon-juniper. Overgrazing, fire suppression, and climatic change have been identified as potential causes of juniper invasion. In the absence of fire or other disturbances, trees eventually dominate the site and crowd out herbaceous and shrub species. Soils: Utah juniper commonly grows on alluvial fans and dry, rocky hillsides, with shallow, alkaline soils.
Utah juniper is considered a "sodium-sensitive" species. Another distinguishing trait is the soft, blue, berry-like cone that can contain up to a dozen seeds. Among the junipers there are two trees, commonly known as cedars. In the east there is Juniperus virginiana, known as the eastern red cedar. And in the mountains of the west coast, grows Juniperus occidentalis, which is usually called a western juniper or Sierra juniper, but on occasion might be labeled as a western red cedar.
According to Scott Leavengood, an associate professor at Oregon State University and director of the Oregon Wood Innovation Center, the common link of all these trees is the aromatic wood. For certain, the wood of the "true cedars" has been widely known for its strong natural odor used to make incense and also for the slight red hue of the freshly cut wood.
When western man discovered the same traits in a few North American conifers, the natural tendency was to label these trees as a cedar, especially because no actual specimens were available in the West. So in the long run, it probably doesn't matter that so many trees from North America bear the name "cedar. For without any alternative system of nomenclature, the widespread use of common plant names could become very confusing. True cedars are members of the genus Cedrus and include species such as the Lebanon cedar, Atlas cedar, and Cyprus cedar.
They are found in the Himalayas and the Mediterranean region and are often grown in parks and gardens. All true cedars are members of the pine family Pinaceae. False cedars, sometimes known as "New World" cedars, are found in North America. They are members of the genera Calocedrus , Thuja , and Chamaecyparis , all of which are part of the Cypress family Cupressaceae.
Some believe that these trees came to be called cedars because of their aromatic wood, which resembles that of true cedars. Cedars are evergreen coniferous trees found throughout the world. They are usually tall and often feature fan-like foliage, small cones, or tiny pink flowers. The major cedars of North America—including the Atlantic white cedar, northern white cedar , giant sequoia, and western red cedar—all have flat, scale-like leaves and stringy bark. They grow in the Northeast, Pacific Northwest, and along the Atlantic coast.
The Japanese red-cedar , originally cultivated in China, is used to produce strong, weather- and insect-resistant timber for building furniture and houses. Other cedars, including the Mexican white cedar and Australian red cedar, are also used to produce durable timber. The Lebanon cedar—one of the true cedars —is mentioned numerous times in the Bible. It was supposedly used in the construction of Solomon's Temple in Jerusalem. Junipers, like cedars, are also evergreen coniferous plants.
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