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Show y 43 FAG Ged TAIN TIMES Window to an Ice Age Big Douglas Fir Trees in the Canyonlands Desert By David B. ost t naturalists Williams would say that Douglas fir shouldn’t grow in the desert where rainfall averages 10-to-12 inches per year. They would ping back in time to a cooler, climate. During the glacial epoch — wetter 22,000 to 11,000 years ago — southeast Utah as much cooler and wetter, in general, relict Forest Islands Could these trees be the last-gasp of earlier glacial eco-systems? Two types of relict communities occur in canyon country: 1) vestigial rem dered in the cooler climate then. The packrat middens also show that snails and crustaceans thrived in canyons that flowed with abundant water [f the Canyonlands grove nants of formerly widespread flora; it would you that these trees typically grow in places like the temperate rain forests of Washington and Oregon, or 2) areas that have not been affected by human activities, particularly livestock grazing continuously inhabited this spot for 20,000 years. Generation after genera tion of trees have survived by remain with annual rain fall averaging over 100 inches Naturalists By definition, most of these areas imply that is a relict, tell Douglas ing rooted in a place fir had favorable to their that are small scale. Isolated buttes and mesas contain grasses and crypto existence. Shaded alcoves, such as this one, appear to be viable locations for Douglas fir should grow in dense forests that cover hundreds of square miles, not in small alcoves biotic soil crusts that have never been grazed. The La Sal Mountains have a subspecies of the small Douglas fir growth Similar refuges exist Canyonlands National Park that cover only a few acres. Yet just 20 miles from Moab, a small grove rodent, called the Pika, living over 100 miles from its nearest relative in Bridges National Monument, adding evidence to the theory that large trees of Douglas fir grows at 5,800 feet, in Colorado. once the heart of the desert. The question is: what are these trees doing here, and could they be evidence of a time long past? In fact, Douglas fir have one of the widest ranges of any North American conifer: 450 miles north into Canada, 800 miles south into Mexico, west to the Pacific Ocean, and east into Colorado. and aspen that grow near this desert alcove are forest islands in a desert Europeans would first tell you encountered although summers were probably drier. Glaciers that spread across the northern part of the country pushed the durous hue diffused a solitary gloom favorable to meditations.” tions than they now only grow Polar Jet Stream south, increasing win- ter precipitation between 35 and 60 percent and dropping temperatures three to four degrees Celsius. These climatic conditions allowed many plants to grow at lower eleva- The scientific name, Pseudotsuga menzeisii, honors Menzies for his contribution. do today. Trees that in the nearby La Sal aS Relicts offer an important window into the past and provide an ecological baseline to begin understanding how humans and climate influence the area. Ecologists are turning to relict grasslands to obtain information on how to restore ecosystems degraded by cattle and sheep grazing. Other communities, like this Douglas fir alcove, may provide a window into the last ice age. By understanding how climate changes over time, ecologists can better understand how our present climate is changing. These fir trees provide an in packrat middens or dens. Starting in the 1970s paleo-ecologists began to analyze the remains accumulated by these inveterate collectors. The grove in the desert near Moab consists of 40 to 50 trees, spread out along about one-quarter Packrat Evidence mile. From a distance the trees look healthy, tucked into a beautiful Since packrats do not travel more than a few hundred feet from their Navajo Sandstone alcove; numerous streaks of desert varnish show the effects of water washing down the homes, any material found in a midden must have grown or lived nearby. Because the animal cements everything in its den together with materials high in carbon, age-dating fir grow of the down a drainage gully, which has a small seep-created pool at its head. They are tall trees, dominating the nearby pinion and juniper. Their narrow, straight profile contrasts with the squat and gnarled pygmy forest trees of the desert. Meandering between the trees, one has a strange feeling of being far removed from the desert. Everything seems different here. The oaks have giant five-inch leaves. Douglas additional piece to this ecological puzzie: : Are these trees a holdout from the last ice age? The answer to this question lies in research conducted Unique Environment of the Douglas covered this red rock land- scape Sed. Douglas fir trees on Vancouver Island, off the west coast of Canada. In 1791, Archibald Menzies, a naturalist on George Vancouver's expedition to the Pacific Northwest, sighted them at Nootka Sound. He wrote: “huge mountains presented themselves covered to their very summits with a continuous forest of stately pines, whose dark ver- trees. Most Likewise, the Douglas fir throughout and Natural remains is a relatively easy process. Cones and needles collected from packrat middens in nearby Arches National Park and throughout Colorado Plateau indicate that the this species of Douglas fir, as well as the limber pine, Pinus flexilis, dominated these landscapes between 20,000 and Abajo Mountains commonly grew The Utah serviceberry towers above. Standing in the main drainage, it smells cool and green, like a forest. Hundreds of purple and white columbine bloom in the areas of the national parks. In fact, the closest Douglas fir to the ones along the alcove wall. It feels like step- Sals. in Canyonlands National Park are 3,000 feet higher and 30 miles away in the La PAGE and 12,500 years ago. Scientist also have found in the packrat dens, evidence of other species no longer present in the region, at all. Along with towering trees, many larger animals lived here: big bison, mammoth, giant sloths, and Harrington’s mountain goats all wan- 17 a aPC ei hiaen Outdoor Enthusiast Demon River Apurimac & m Paper $16.95 The First + Navigation of the Upper , Amazon | Canyons ‘J. Calvin Giddings The deep, turbulent gorges of the Apurimac provide the greatest suspense of this story, but the author's gripping account also offers keen observations of the remarkable wildlife and canyon landscape, as well as several memorable encounters with the indigenous people of the region. “Like the Amazon itself, this book gains power as it flows.” —John Calderazzo, Colorado State University Fishes _ of Utah ~ A Natural History William F. Sigler and John W. Sigler | Illustrations by Joseph R.Tomerelli \ | Cloth $99.95 Despite being the second driest state in the U.S., Utah is home to a surprising number of fishes, both native and introduced. 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