Winter Pea Crop Rotations as an Approach to Make Summer Irrigation Water Available for Temporary Water Sharing Arrangements
Funded by the Colorado Water Conservation Board
With most Colorado water rights used for agriculture, farmers continually seek options to increase the conservation and efficiency of agricultural water use. While Alternative Transfer Methods are proposed to conserve water while limiting negative impacts on agriculture, many ATMs have dubious benefits for agricultural sustainability. Winter cropping, however, is an option for farmers who wish to keep land in production and support soil health while participating in summer water sharing arrangements.
This project will develop knowledge that offers an alternative to current approaches to managing farmland enrolled in water-sharing programs. Previous research has demonstrated that winter peas are one of the most viable grain legumes for the upper Colorado basin due to their shorter growing season and winter hardiness. This project will be undertaken at the Western Colorado Research Center in the Grand Valley, which has a stated mission to develop new cropping systems to meet the realities of ongoing water stress in the basin.
The project objectives are to evaluate the feasibility of a crop regimen based on growing winter pulses to reduce summer irrigation water demand and offer producers additional revenue sources through water sharing arrangements; to develop a planting, management, and harvest schedule that optimizes profit for farmers who wish to grow winter peas on parcels that may be entered into water sharing arrangements; and to engage with Western Colorado producers to improve knowledge needed to grow winter peas in the context of intentional water supply limitations and foregone irrigation diversions.
We will grow five varieties of winter peas under furrow irrigation with three treatments: no spring water at all, a May 1 irrigation cutoff, and a June 1 irrigation cutoff. We will develop a cropping budget that will consider the income from peas, income from water banking, grazing income, and fertilizer and seed costs.