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Early Ponderosa Pine Forests: Notes on Fire Ecology

Author(s): Stephen F. Arno
Year Published: 2021

Wildland fire shaped the historical ponderosa pine and mixed-conifer forest landscapes throughout the West. Fire was also a controlling force in most of the drier vegetation types, ranging from shortgrass prairie to chaparral, scrub oak, and pinyon–juniper woodlands. It is therefore no surprise that wildland fire suppression in all of these landscapes has had profound effects. OPEN-GROWN CONDITIONS Ponderosa pine ranges from Mexico to Canada, covering about 40 million acres (16 million ha) across parts of most Western States. Historical photos and accounts of southwestern ponderosa pine forests document their open-grown conditions, with an undergrowth of luxuriant grass. In a 1960 monograph about changes in southwestern pine forests since white settlement, Charles Cooper cited a number of locations and sources (Cooper 1960). In 1857 and again the following winter, Lieutenant Edward Beale led a famous corps of camels that was expected to revolutionize transportation across the Southwest. In what is now northern Arizona (on the Coconino National Forest), Beale described “a glorious forest of lofty pines, through which we have travelled ten miles [16 km]” (Lesley 1929). He recorded seeing “beautiful, broad grassy vales extending in every direction. The forest was perfectly open and unencumbered with brush wood.” Joseph Rothrock, a botanist with the Wheeler Survey of 1875, described the region just south of Gallup, NM (Cooper 1960): Gaining the summit, a thousand feet [300 m] above Fort Wingate, we were at an altitude of about 8,000 feet [2,400 m] above the sea, a fine, open, park-like region with a large growth of yellow pine [ponderosa and fir] covering the hillsides. A diversified herbaceous vegetation was out in the most brilliant colors, beautifying alike the woods and open grounds. ... Good forage was abundant. Cooper (1960) described the same area as “almost bare of herbaceous ground cover, and dense thickets of pine saplings predominate.” Clarence Dutton’s 1887 U.S. Geological Survey report on the Grand Canyon Region said of the Kaibab Plateau (Biswell 1972): The trees [ponderosa] are large and noble in aspect and stand widely apart, except part of the plateau where spruces [likely Douglas-fir] predominate. Instead of dense thickets where we are shut in by impenetrable foliage, we can look far beyond and see the tree trunks vanishing away like an infinite colonnade. ... There is a constant succession of parks and glades—dreamy avenues of grass and flowers .... From June until September there is a display of wild flowers which is quite beyond description. (more)

Citation: Arno SF. 2021. Early Ponderosa Pine Forests: Notes on Fire Ecology. Fire Management Today V79(4): 36-39.
Topic(s): Fire Ecology, Fire Effects, Fire History
Ecosystem(s): None
Document Type: Book or Chapter or Journal Article
NRFSN number: 23950
Record updated: Jan 3, 2022