By Karie Boone, Center for Sustaining Agriculture and Natural Resources, Washington State University, and Clark Seavert, Oregon State University
For the inland Pacific Northwest, climate change predictions including wetter springs and drier, hotter summers leads to production system uncertainties and risks for dryland, small grain farmers. Annual precipitation is projected to increase by about 5-15% by 2050 except during the summer months where precipitation is projected to decrease, resulting in decreased soil moisture during the late summer months. We have seen conditions similar to these projections in recent years, such as the droughts in 2015 and 2021 and a wet spring in 2019 that prevented planting almost 53,000 acres across Washington, Idaho, and Montana.
These changes are expected to increase reliance on fallow for small grain dryland systems. Fallowing strategies can lead to further declines in organic matter inputs, soil health, and reduced production capacity in the future. Potential alternatives attractive to producers include incorporating winter pea into rotations and planting cover crops coupled with livestock grazing. But will they be profitable?
Growers who are considering alternatives to fallow, such as legumes or forage crops, can use a new profitability tool to understand the impact on their bottom line, including impacts to the profitability of their main wheat crop. The Economic Model to Compare Crop Rotations is an excel spreadsheet that assists dryland growers of the inland Pacific Northwest in comparing the whole-farm net returns of an alternative crop rotation, compared to their Business as Usual (BAU) rotation.
Alternative rotations are potentially relevant in wetter annual cropping zones, where a crop is normally grown every year. While these areas have greater crop diversity, wet springs in recent years have prevented planting of spring crops. When this happens, the land remains fallow, and vulnerable to water erosion. Winter peas and cover cropping consumes more water than a spring crop which minimizes runoff and is easier to plan. Replacement of spring wheat with winter pea also eliminates a year of nitrogen fertilizer, increasing profitability.
The economic tool being introduced here is intended for use by farmers to explore the conditions under which these alternative rotations may make sense for their operation. The tool is available for download in spreadsheet form and should be familiar to anyone who has a basic knowledge of spreadsheets. And we have developed a series of short, instructional videos that walk you through how to use it.