Exploring Whether Washington State Could Become the New California in Vegetable Production

By Fidel Maureira, Ph.D. Candidate, Department of Biological Systems Engineering, Washington State University

Climate variability and change—rising temperatures, more frequent heat waves, drought, less snowpack, pests and diseases, wildfires, and the resulting over-use of resources such as groundwater—are creating critical agricultural production risks for California, the leading vegetable and fruit producing area of the United States. These issues are projected to get worse in the future. In contrast, climate change-related challenges in the Columbia River Basin are projected to be less extreme and there is potential for a more favorable climate for certain agricultural products, providing the Columbia River Basin with relative competitive advantages over California. Can the irrigated areas of Washington State supplement some of the expected losses in vegetable production in California? The answer is not clear yet, but we are exploring the implications of increasing vegetable production in the Basin, using climate change projections and models that quantify how regional hydrology and crops would respond to those climatic changes (Figure 1).

Although vegetable crops such as potatoes, sweet corn, onions, and green beans are important crops in the Columbia River Basin, there is potential to consider new crops as well. In fact, there is evidence of past production of crops that are not currently prevalent; for example, tomatoes in the early 1900s (Figure 2). Additionally, some growers are currently taking the initiative of growing new vegetable crops in response to retailers looking for local sources. Currently, 7% of the vegetables offered by Walmart are locally produced. An example is the Imperial’s Garden, owned by a family business located in the Yakima Valley, that produces more than 1,300 acres (526 ha) of asparagus, sweet corn, peppers, melon, and tomatoes, among many other vegetables. They sell to groceries all around the Pacific Northwest.

But why should we invest effort in understanding what an expansion of vegetable production in Washington State would mean? Because such changes in agricultural production could increase the water demand for crops and, where curtailments already point to limited water resources, an extra demand of water can build up to restrictions for other uses, such as energy generation, navigation, or wildlife.

To understand the implications of a vegetable production expansion, we will use simulation models to evaluate the feasibility of introducing new, open-field vegetable crops in the irrigated areas of Washington State. We are focusing on the production of open-field vegetables, as it would keep most of the investments that growers have already made to produce existing crops, like central pivot systems and tractors. Using an agricultural land-use and CropSyst model, we will evaluate different scenarios that include changes in cropland use, and factors outside producers’ direct control, such as increasing demands for food by 2050, and more suitable weather conditions in the region relative to other, out-of-state producers. Our proposed steps (Figure 3) include using CropSyst (a crop model developed at Washington State University with the ability to predict biomass and yield given the weather, soil and crop management conditions) to:

1. Simulate the growth, yield, water use, and nitrogen losses of existing crops and proposed new vegetable crops under current and future climate scenarios;
2. Determine the enterprise production budget for each crop, that estimates the costs and revenues associated with each of the cases simulated in step (1);
3. Estimate the trade-offs between the economic benefits to growers, obtained from step (2), and the environmental impacts, such as greenhouse gas emissions and water use, obtained from step (1);
4. Estimate the optimal change in crop types, considering the trade-offs in step (3) and adding a critical production area constraint: the minimum production of a given vegetable crop needed to justify the establishment of processing plant facilities.

Now is the time to better understand how the expansion of vegetable production in Washington State could affect the reliability of water available for irrigation, or the impacts on agricultural water demand and how that might affect competing uses of water (for example for energy generation), and what environmental impacts the new crop production might have. We can also better understand whether innovative storage management, such as managed aquifer recharge, could affect the trade-offs between the food, energy, and other sectors. By doing so, we hope to provide decision-makers with better information as they determine if, when, and how to manage for or around future changes in vegetable production in Washington State.

This article was revised from the original version, titled “Will Washington State Supplement Some of California’s Expected Losses in Vegetable Production?” published in November 2019 as part of the following report: Hall, S.A., Yorgey, G.G., Padowski, J.C., Adam, J.C. 2019. Food-Energy-Water: Innovations in Storage for Resilience in the Columbia River Basin. Progress Report for the Columbia River FEW Project. Available online at www.fewstorage.wsu.edu.

References:

Pathak, T., Kearns, F., Maskey, M., Dahlberg, J., Bali, K., Zaccaria, D., 2018. Climate Change Trends and Impacts on California Agriculture: A Detailed Review. Agronomy 8, 25

Stöckle, C.O., Higgins, S., Nelson, R., Abatzoglou, J., Huggins, D., Pan, W., Karimi, T., Antle, J., Eigenbrode, S.D., Brooks, E., 2018. Evaluating opportunities for an increased role of winter crops as adaptation to climate change in dryland cropping systems of the U.S. Inland Pacific Northwest. Clim. Change 146, 247–261

Data publicized by USDA, NASS as Production of wheat and tomato.

Favor, E.H. 1911. The Fruit-Growers Guide-Book. The Fruit Grower. St. Louis, MO. 285 pp.

The work described in this article was supported jointly by the National Science Foundation under EAR grant #1639458 and the U.S. Department of Agriculture’s National Institute of Food and Agriculture under grant #2017- 67004-26131, as well as the Washington State University Graduate School.