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Lost Forest Research Natural Area
The Lost Forest Research Natural Area is a designated forest created by the Bureau of Land Management to protect an ancient stand of ponderosa pine in the remote high desert county of northern Lake County, in the southeastern portion of the U.S. state of Oregon. Lost Forest is an isolated area of pine trees separated from the nearest contiguous forest land by forty miles of arid desert. There are no springs or surface water in Lost Forest, and much of the southwest portion of the natural area is covered by large shifting sand dunes that are slowly encroaching on the forest.
== Geology ==
Lost Forest is located at the northeastern corner of the Christmas Lake Basin in south central Oregon. The bedrock beneath the area was created by basalt flows laid down during the Pliocene and Pleistocene epochs. After a period of intense faulting during the middle Pleistocene, a large basin area was created by erosion and sedimentation. This basin filled with water during the wet climatic periods of the Pleistocene and post-Pleistocene. Over the past 3,200 years, the surface water in the Christmas Lake Basin has completely dried up, leaving an arid high desert environment.〔Moir, William H., Jerry F. Franklin, and Chris Maser, (''Lost Forest Research Natural Area'' ), Pacific Northwest Forest and Range Experiment Station, United States Forest Service, Department of Agriculture, Portland, Oregon, 1973.〕
Today, the Lost Forest area is generally flat with gentle swales. The base elevation is above sea level. However, there are a number of basalt outcroppings that rise above the surrounding terrain. There are also large moving sand dunes in the southwest corner of the natural area. These dunes are made up of lacustrine sediments, Aeolian deposits, and alluvial materials with large amounts of volcanic pumice and ash mixed into fine sand.〔("Lost Forest Research Natural Area" ), ''Research Natural Areas'', Lakeview District, Bureau of Land Management, United States Department of Interior, Lakeview, Oregon, 24 May 2009.〕 Most of the dunes occurred west and south of the Lost Forest; however, there has been some shifting of sand from the dry lakebed of Fossil Lake through portions of the pine and juniper stands in the southwest section of the natural area. Some trees have been killed and others partially covered and then uncovered later as the sand moved through the area. While the dunes kill some trees, they do not appear to threaten the forest in general.〔Chadwick, Kristen L. and Andris Eglitis, (''Health Assessment of the Lost Forest Research Natural Area'' ), Central Oregon Service Center for Insects and Diseases, United States Forest Service, United States Department of Agriculture, Bend, Oregon, February 2007.〕
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