Curtis F. Marbut
Encyclopedia
Curtis Fletcher Marbut (1863–1935) served as Director of the Soil Survey Division from 1913 until his death in 1935. Marbut developed the first formal soil classification scheme for the United States.
Marbut was born and raised in Barry County, Missouri
. He obtained a Bachelor of Science from the University of Missouri
in 1889 and a Master of Arts degree from Harvard University
in 1894. (He never sat for his final PhD exams at Harvard ). Marbut taught Physiography and Geology at the University of Missouri from 1895 until 1910, and also worked for the Missouri Geologic Survey and directed the Missouri Soil Survey.
In 1910, Marbut went to work as a Soil Scientist in the Bureau of Soils of the U.S. Department of Agriculture, where he continued until his death in 1935. Marbut became Director of the Soil Survey Division in 1913. Marbut died of pneumonia in 1935 while en route to an assignment in China advising the Chinese Geological Survey on organizing a Soil Survey.
As a geologist and geographer his initial view was that soils were surface reflections of the geology below them. Marbut changed to recognize soil science as distinct from geology. Eugene W. Hilgard
of the University of California and Hopkins of the University of Illinois greatly influenced this change. The land-grant universities from the very start were close partners in National Cooperative Soil Survey. By 1920, most soil surveyors were graduates of land-grant universities and other agricultural colleges with training in soils and crops.
In 1920 Marbut began his work on a soil classification scheme. In 1927 he published a translation of Glinka's The Great Soil Groups of the World and their Development from German to English. His classification scheme became the 1935 system that was modified to become the system published in the 1938 Yearbook of Agriculture, Soils and Men: the 1938 USDA soil taxonomy. At the highest level of classification the soils were divided into pedocals
and pedalfers
. Pedocals were used in the drier climates and referred to the carbonate rich soils. The Pedalfers began about at the Udic border and referred to soils rich in Aluminum (Alumen) and Iron (Ferrous). Alfer became the root term for Alfisols.
Marbut was born and raised in Barry County, Missouri
Barry County, Missouri
Barry County is a county located in the U.S. state of Missouri. As of 2010, the population was 35,597. Its county seat is Cassville. The county was organized in 1835 and named after William Taylor Barry from Kentucky, a United States Postmaster General....
. He obtained a Bachelor of Science from the University of Missouri
University of Missouri
The University of Missouri System is a state university system providing centralized administration for four universities, a health care system, an extension program, five research and technology parks, and a publishing press. More than 64,000 students are currently enrolled at its four campuses...
in 1889 and a Master of Arts degree from Harvard University
Harvard University
Harvard University is a private Ivy League university located in Cambridge, Massachusetts, United States, established in 1636 by the Massachusetts legislature. Harvard is the oldest institution of higher learning in the United States and the first corporation chartered in the country...
in 1894. (He never sat for his final PhD exams at Harvard ). Marbut taught Physiography and Geology at the University of Missouri from 1895 until 1910, and also worked for the Missouri Geologic Survey and directed the Missouri Soil Survey.
In 1910, Marbut went to work as a Soil Scientist in the Bureau of Soils of the U.S. Department of Agriculture, where he continued until his death in 1935. Marbut became Director of the Soil Survey Division in 1913. Marbut died of pneumonia in 1935 while en route to an assignment in China advising the Chinese Geological Survey on organizing a Soil Survey.
As a geologist and geographer his initial view was that soils were surface reflections of the geology below them. Marbut changed to recognize soil science as distinct from geology. Eugene W. Hilgard
Eugene W. Hilgard
Eugene Woldemar Hilgard was a German-American expert on pedology...
of the University of California and Hopkins of the University of Illinois greatly influenced this change. The land-grant universities from the very start were close partners in National Cooperative Soil Survey. By 1920, most soil surveyors were graduates of land-grant universities and other agricultural colleges with training in soils and crops.
In 1920 Marbut began his work on a soil classification scheme. In 1927 he published a translation of Glinka's The Great Soil Groups of the World and their Development from German to English. His classification scheme became the 1935 system that was modified to become the system published in the 1938 Yearbook of Agriculture, Soils and Men: the 1938 USDA soil taxonomy. At the highest level of classification the soils were divided into pedocals
Pedocal
Pedocal is a subdivision of the zonal soil order. It is a class of soil which forms in semiarid and arid regions. It is rich in calcium carbonate and has low soil organic matter. With only a thin A horizon , and intermittent precipitation calcite, other soluble minerals ordinarily removed by water...
and pedalfers
Pedalfer
Pedalfer is composed of aluminum and iron oxides. It is a subdivision of the zonal soil order comprising a large group of soils in which sesquioxides increase relative to silica during soil formation. Pedalfers usually occur in humid areas...
. Pedocals were used in the drier climates and referred to the carbonate rich soils. The Pedalfers began about at the Udic border and referred to soils rich in Aluminum (Alumen) and Iron (Ferrous). Alfer became the root term for Alfisols.