This summer, like every summer, a cornucopia of Colorado grown foods are beginning to appear at grocery stores and farmers markets. Coloradoans will once again be biting into juicy Palisade peaches and ripe Rocky Ford cantaloupe. What is the primary ingredient of these delicious products? Water. Cantaloupe and peaches are about 90 percent water. And that hamburger – which might have come from a steer raised in Rio Blanco County – about 60 percent water.
It takes a lot of water to grow food – but the amount that ends up in the food itself is a small part of the story. More than 99 percent of the water used by irrigated crops or grass is drawn through the roots and transpired through the leaves, according to USDA and Colorado State University. Less than 1 percent of the water taken up by plants is actually used to produce plant tissue. In other words, crops and forage use a lot of water to conduct photosynthesis and manage heat stress.
The water used by plants is called evapotranspiration (ET). Evapotranspiration is the water use that occurs through the processes of evaporation and transpiration. Evapotranspirative losses are determined by solar radiation, temperature, humidity and wind. The highest plant ET occurs on hot, windy days. In Colorado, irrigation water rights are based on the historic ET of the crops grown plus any transit water that is needed to deliver the water from the source to the field.
Visit https://www.agwaternetwork.org/Publications.aspx to see the full article with details and stay tuned next week for the second part of this series!
By Guest Writer Phil Brink, Consulting Coordinator, Colorado Cattlemen’s Ag Water NetWORK (agwaternetwork.org) — PAID CONTENT