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Mechanized maneuver training can impact soil quality in many ways, most notably through soil displacement and compaction. To identify indicator variables for inclusion in monitoring programs on military lands, a replicated small‐plot study of tracked vehicle disturbance effects on tallgrass prairie soil properties was initiated on Fort Riley, KS, in 2003. A range of disturbances encompassing soil surface texture, environmental conditions, and traffic intensity were evaluated. Soil physical (rutting and compaction) and chemical (soil organic matter and nutrients) properties were monitored annually on curve and straightaway track areas through 2007. Rut depth remained significant (P ≤ 0.05) for curves of inside and outside tracks in both soil surface textures throughout the study and was more severe for repeated vs. single traffic events. Bulk density increased with disturbance under wet soil conditions, repeated traffic, and on curve areas but recovered to undisturbed levels within 1 to 3 yr. Soil compaction as measured by penetrometer resistance was more severe for traffic under wet soil conditions and remained significant (P ≤ 0.05) at depths of 5 to 10 cm in both soil surface textures throughout the study. Residual effects of tank traffic on soil chemical properties were generally mild, but soil C was reduced following disturbance under wet soil conditions, repeated traffic, and on curve areas and required 3 to 4 yr to recover to undisturbed levels. The results of this study emphasize the importance of suitable impact management to maintain the sustainability of tallgrass prairie for military training activities.

The Department of Defense's Range and Training Land Assessment program provides information and recommendations to range managers regarding the condition of training lands. This information is used to assist in scheduling training areas and in monitoring the effectiveness of rehabilitation projects. Fort Riley Military Installation is a major training reservation located in the Flint Hills of northeastern Kansas, within the tallgrass prairie ecosystem. A randomized complete block design composed of three treatments (M1A1 Abrams tank traffic during wet and dry soil conditions, and a nontrafficked control) with three replications was established in each of two soil types, a silty clay loam and a silt loam soil, on Fort Riley in 2003. Disturbance was created by driving the tank for five circuits in a figure-eight pattern during either during wet or dry soil conditions. Two additional experimental treatments were added during the study: five additional tank passes on one-half of each figure eight in 2004 and burning in 2006. Two areas, a curve and straightaway, within each traffic intensity (and later, burn treatment) subplot were designated for sampling. Aboveground biomass, species composition, and ground cover were measured during each growing season. Recovery of grass and total aboveground biomass in silty clay loam soil was delayed for curve areas and following disturbance in wet soil conditions, respectively. Species composition and ground cover continued to exhibit significant disturbance effects in 2007, with greatest damage observed for repeated traffic under wet soil conditions. Fire effects on vegetation were variable and generally greater for undisturbed control plots than for disturbed areas. The tallgrass prairie typically is considered to be among the most resilient of military training lands, but our research suggests that resiliency is dependent upon soil type and training conditions, and may require longer periods of recovery than previously thought. Resumen El programa de entrenamiento y valoración de Tierras del Departamento de Defensa provee información y recomendaciones a los manejadores de pastizales sobre la condición de las tierras de entrenamiento. Esta información se utiliza en la selección de áreas de entrenamiento así como para el monitoreo de la efectividad de los proyectos de rehabilitación. Las instalaciones militares del Fuerte Riley es una importante reservación de entrenamiento localizada en Flint Hills al noreste de Kansas, dentro de los ecosistemas de praderas de pastos altos. Un diseñ o de bloques al azar, compuesto de tres tratamientos (Tráfico de tanques Abrams M1A1 bajo condiciones de suelo húmedo y seco, y un área control sin tráfico), con tres repeticiones se establecieron en dos sitios con diferente tipo de suelo, un suelo limo-arcilloso y un suelo limoso en el Fuerte Riley en 2003. El disturbio fue creado mediante la conducción del tanque en cinco circuitos en forma de ocho durante condiciones de suelo húmedo o suelo seco. Se incluyeron otros dos tratamientos experimentale...

Journals published by the American Society of Agronomy (ASA) richly chronicle the growth and success of agronomic education. To commemorate the 100th anniversary of Agronomy Journal, we compiled this historical recognition of the aggregate effort of our predecessors and colleagues. Their talented and dedicated legacy has played a significant role in feeding the world while protecting soil and water resources. By consulting our past we seek wisdom for the future, knowing that educational challenges of equal significance wait. The first volume (1909) included an article on instruction in soil physics and approximately 650 more education articles have since appeared. Most early articles focused on soils and crops course descriptions and their need for standardization. Then emphasis switched to teaching methods, aids, philosophies, student characteristics, evaluation, and curricula. Contributions from land‐grant institutions have been most numerous, but other sources are becoming more common. The number of articles has steadily increased, as has author collaboration on articles, growing from only about 10% in early years to about 70% in recent editions. We hope our abbreviated summary of the past stimulates you into consulting the writings of your esteemed predecessors and that you find validation of your efforts toward making a difference in some future agronomic record. As global pressures increase the demands on agronomic education, history may provide a pattern for success. Past achievements suggest that agronomic education is well‐founded and can be expected to impact the next century of learning as capably as it did its first century.