(May 04, 2018) - The advent of no-till farming created an opportunity for more water-use-intensive cropping systems.
Annual forages offer a way of increasing the cropping intensity of traditional fallow-wheat systems, without taking on the risk of annually cropped systems harvested for grain. Pea, and especially winter pea, is not well studied as a forage in dryland systems.
In a paper recently published in Agronomy Journal, researchers report forage yield and quality of barley and pea managed with early and late harvest dates, and their effects on soil water and nitrogen, and subsequent wheat, over four years in southwestern Montana.
Protein yield for spring and winter pea forage was 60% and 81% greater than the barley forage treatments, averaged across harvest timings and years. Soil water and nitrate use at the late forage harvest stage was more similar to grain harvest than it was to early forage harvest, but at this wet-wintered field site, these soil differences produced little effect on subsequent wheat.
Wheat following spring and winter pea forage averaged 82% to 88% of the yield on chemical fallow. Farmers would need to decide for their operations if net forage value and potential cost savings from chemical fallow outweigh a 12% to 18% yield reduction in subsequent wheat.