Land use in south-central Oklahoma and north Texas has changed greatly since the 1930s and 40s when Lloyd Noble, founder of Noble Research Institute, saw the devastation of the soil and committed himself to making a difference to help the region. Today, row crop agriculture has been largely replaced with forage-based beef cattle production systems, and the landscape is now a mosaic of woodland, rangeland, pasture and small grain cropland. The many gullies and shallow soils in the region remind us that not all agricultural production systems are equal with respect to soil protection and sustainability.
Still today, the choices we make impact production efficiency and sustainability. As an example, many rangelands today burn less frequently than was common before European settlement. As a result, juniper and other woody plant species are increasing. This begs several questions: What are the long-term consequences of continuing to avoid fire? If we choose to reintroduce fire, what is the appropriate frequency? What is the appropriate scale? What effect will frequent fire have on plant and animal productivity, soil erosion risk or risk of exotic weed invasion? What are the costs of conducting prescribed burns? The Agricultural Research Team is a multidisciplinary team of scientists working together to answer these and other questions that arise from land management alternatives.
With a background in soil and rangeland sciences, my contributions to the research team will focus on soil conservation, plant ecology, hydrology, grazing, agronomy and remote sensing. One of my first Noble Research Institute projects, Burning of cross-timbers: Effects on vegetation, wildlife habitat, stocker cattle production and economics, is a good example of the multidisciplinary approach of the Agricultural Research Team. One aspect of this project I will lead is to evaluate very-large-scale aerial (VLSA) imagery as a tool for characterizing rangeland vegetation in the region. As Lloyd Noble, an aviation pioneer, knew well, there is much to be learned about the state of the land from a bird's-eye view.
VLSA technology was developed by scientists with the USDA Agricultural Research Service in Cheyenne, Wyo., and has proven to be an extremely useful and efficient tool for sampling vegetation in the sagebrush steppe of eastern Idaho and other western rangeland areas. The imagery is spatially discontinuous, meaning that it covers only a fraction of the landscape. Each image shows an area that is approximately 21 ft. by 14 ft. VLSA image resolution is much greater than is available in other remote sensing products. VLSA image pixels are about 1/20 inch on a side compared with 40-inch pixels in other generally available imagery such as the USDA's National Agriculture Imagery Program (NAIP).
We hypothesize that VLSA imagery will be useful for identifying and quantifying many woody species, forbs and grasses as well as for detecting and quantifying bare ground, litter and rock. One of the many advantages of VLSA imagery is sampling efficiency. For example, nearly 1,300 locations will be sampled in the burning study mentioned above in less than five hours of flight time, whereas collecting detailed data at the same locations would require a two-person team months to complete. Stay tuned until 2011 as we complete our evaluation of this promising tool.