Oklahoma to Study Eastern Redcedar Encroachment
Oklahoma State University’s Division of Agricultural Sciences and Natural Resources will receive $226,890 in grant funding from the U.S. Geological Survey, provided through the Oklahoma Water Resources Research Institute (OWRRI).
OWRRI and USGS officials are funding the division study on eastern redcedar encroachment and the water cycle in the tallgrass prairie, two key elements of ecosystem health for Oklahoma.
“Oklahoma is one of the key U.S. locales where woodlands meet grasslands,” he said. “Changes in vegetation have a great effect on water cycles and the recharging of groundwater supplies. This, in turn, affects every aspect of water use, be it by people or wildlife,” explained Chris Zou, assistant professor with the OSU Department of Natural Resource Ecology and Management and principal investigator of the study.
In the Great Plains, tallgrass prairie is rapidly transforming to woodland largely because of the encroachment of eastern redcedar trees.
“Of Oklahoma’s 17 million acres of rangeland including prairie, 8 million acres are currently overgrown with eastern redcedar,” said Dave Engle, holder of OSU’s Thomas E. Berry Endowed Chair in Integrated Water Research and Extension. “That number is increasing at an alarming rate, equivalent to 762 acres a day.”
One of the vital elements of the study will be to determine specific data about how the encroachment of eastern redcedar trees in tallgrass prairie alters the dynamic response between precipitation and water loss through vegetation canopy interception.
Another important aspect will be to determine more exactly how redcedar encroachment increases root depth and alters seasonal water-use patterns.
The study will also examine the degree to which eastern redcedar encroachment can reduce stream flow production at the watershed level.
Engle, who serves as director of the division’s Water Research and Extension Center, said proliferation of woody plants is a challenge to rangeland managers across the globe.
“It’s both an economic and ecological issue, mainly because water-use efficiency by people, plants and wildlife affects everyone and everything in the long run,” he said. “Water, by its very nature, is a highly interconnected and integrated natural system.”
“In our public meetings regarding the water plan, we heard from many citizens – particularly the agricultural community – who were concerned about the impact of cedars on water availability,” said Mike Langston, OWRRI assistant director. “The magnitude of their impact is not well understood. We believe this is an important study to help the state plan for the future.”