Trees, grassland and water use as a zero-sum game
Did J. Sterling Morton get it all wrong?
We won't go that far, but a recent report delivered to local Natural Resources Districts does seem to indicate that attempts to reinvent the prairie in the image of the father of Arbor Day's native, tree-covered Michigan are misguided.
The use of water is a zero-sum game, and consumption of precipitation by grassland and trees leaves less for crops and, more importantly for legal purposes, less to send down the Republican River to Kansas.
The Republican River Basin Water Balance Study report presented at the Middle Republican NRD Tuesday night showed just that.
Riparian forests -- wooded areas near rivers, about the only kind that exist in Southwest Nebraska -- and woodlands use more water per acre than any other land use, including crops, according to the study.
Riparian forest and woodlands use 4.26 acre feet of water a year or 51.2 inches of average annual consumption.
By comparison, irrigated corn uses 2.34 acre feet of water, or 28.1 inches of average annual consumption.
An acre-foot is the amount of water it takes to cover an acre of land one foot deep in water, or 325,851 gallons.
It shows that trees, especially those with root systems that reach deep, consume a lot of water," said Frank Kwapnioski of H20 Options Engineering LLC of Lincoln, Nebraska.
The study seemed to show a link between water consumed by trees and grass and the overall decrease in surface water, he said.
"In the 1930s, the landscape was different than it is now, which may describe the change being seen in overall surface water," he said, "though there are many factors, not just one."
The problem is, the Republican River Compact conflict, which threatens agriculture in Southwest Nebraska, was signed -- by the State of Nebraska, we must add -- with that 1930s landscape in mind, rather than modern conditions that exist following decades of conservation efforts and growth of trees and underbrush.
We enjoy trees and feel they add much to our communities. However, a new river agreement should be negotiated with modern conditions taken into account.