Fort Valley Experimental Forest Station

The study of ponderosa pine regeneration in northern Arizona’s Fort Valley Experimental Forest Station helps us preserve the nation’s unique forests after damage and depletion caused by excessive logging and livestock grazing.

Fort Valley, in northern Arizona near Flagstaff, is unique in its abundance of native grasses, water from the Leroux Springs, and plethora of ponderosa pines. The demand for timber from logging and railroad companies as well as livestock grazing began to threaten the region's isolated vegetation during the late 1880s, as loggers noticed that the ponderosa pines were not regenerating after cutting. To address this issue, Arizona Lumber and Timber Company owners Timothy and Michael Riordan invited the Chief of the Forest Service, Gifford Pinchot, to visit the area in 1891. The Riordans also hosted biologist C. Hart Merriam and the chief of the Division of Forestry, Bernhard E. Fernow in 1896. Fernow and Pinchot worked with foresters Raphael Zon and Gustaf Pearson to urge the federal government to set aside the area as part of the Forest Reserves, now known as National Forests. The Forest Service granted their request, and established the Fort Valley Experimental Forest Station in 1908 to study high-altitude ponderosa pine regeneration, with Pearson serving as the station’s first director until his retirement in 1944.

The station started a summer training school for rangers in 1909, and through the 1910s and 1920s, its workers focused on researching the effects of cattle grazing and ways to improve range production through water development, fence building, removal of poisonous plants, and growth of supplemental pasture grass to aid the regeneration of natural vegetation. During this time, it also began keeping weather records and constructed six meteorological observation locations to detect how elevation changes affected seed regeneration of ponderosa pines. Foresters also developed long-term studies to explore natural and artificial regeneration, how disease and pests distressed growth, and began attaching identification tags to help scientists monitor the lives of individual trees.

The Civilian Conservation Corps assisted by providing water access to Leroux Springs, a greenhouse, and electricity during the 1930s, and a 1931 Forester’s Order from the federal government established the station as part of Coconino National Forest lands, which protected it from logging, hunting, and cutting. Throughout the 1940s, the Forest Service expanded the land holdings of the Fort Valley Experimental Forest, and began working with the Arizona State College’s (now Northern Arizona University) new School of Forestry by using the station as a field site for its research facilities in 1958. In 1960, the U.S. Geological Survey used some of its structures to record and measure the earth’s magnetic forces and underground movements, research which later helped establish plate tectonics theory.

Through the 1950s to the 2000s, research shifted to include long-term studies on watershed management, wildlife habitats, and how wildfires and prescribed burning affect the regeneration and diversity of native and invasive plants. Fort Valley still collaborates with NAU’s School of Forestry and the U.S. Forest Service. In 2001, it was added to the National Register of Historic Places and continues to research best forest management techniques in order to preserve the region’s unique ponderosa pines.