These tiny pollinators are perfect partners for success.
Walla Walla County in Washington state produces a significant portion of the nation’s alfalfa seed, and that’s partly thanks to the love farmers there have for their bees.
“They are literally part of the family. I grew up with them,” says Mark Wagoner, a third generation farmer. “We have about 30 acres of ground dedicated just to alkali bees. You can’t buy them; you have to have them reproduce.”
The native bees are crucial because they support the production of one of the only crops that can thrive in such harsh summer growing conditions.
“About the only thing we can grow here is alfalfa seed. We rotate it with wheat and grow a little bit of seed peas, but we just can’t grow crops that need water in the summer.”
Building Bee Beds
Intentionally sourcing or managing bees for pollinator services is not unique. However, most crops rely on honeybee pollination, which isn’t ideal for alfalfa seed.
The fused lower petals of the flower form a boat-shaped structure around the reproductive organs called a “keel” and in order to reach the pollen, bees must pop open the flower. Alkali bees are skilled at performing this “tripping” action, while honeybees often learn to avoid it and forage nectar from the side without reaching the pollen.
In the 1950s, Herman Menke, a professor at WSU, began studying the bees. While there are natural bee beds near the Walla Wall River, growers have been creating their own artificial habitats for over 75 years using underground pipes that provide subsurface water in the spring and early summer to keep the ground moist. Then, growers do something most farmers would never do; they add salt to the soil.
Many growers have built bee beds on hillsides or other areas that wouldn’t be suitable for farming. And due to the lack of rainfall, runoff issues are not really a concern.
“In the Touchet and Gardena areas, they only get about 6 or 8 inches of rain a year at most and most of that is between November and April,” says Doug Walsh, professor of entomology at Washington State University.
“The managed bee beds mimic desert habitats where the upwelling of springs resulted in salt accumulation and moist locations for the bees to nest in,” Walsh says.
Pollinator Partners
While the alkali bees are important, alfalfa seed farmers elsewhere buy leafcutter bees from Canada, and in fact, Walla Walla growers also purchase leafcutter bees to work alongside the alkali bees in the fields.
The leafcutter bees are expensive, but seed growers need them because the alkali bee population and their emergence are dependent on environmental conditions.
“With the leafcutter bees, growers have incubation chambers to keep them in and they can stagger the release as needed,” Walsh says.
Walsh has done some research using plastic mulch that could give farmers some influence over the timing of the alkali bee emergence, but no growers have adopted it yet.
In addition, the leafcutter bees are seemingly able to handle the heat of late summer a little better. Once the bees emerge in early June, female alkali bees have only about six weeks to mate, nest, forage and raise a brood.
Other native bees also provide pollination.
“I think they’ve found 15 native bees in our area, but we don’t know how to manage them yet,” Wagoner says.
He says it’s difficult to measure just which type of bee is the most important pollinator for the crop, because once the blossom is tripped, it stays open, and may be visited by multiple bees over the rest of the season. However, the yields provide some compelling evidence.
Growers in Touchet area tend to get yields between 1,200 and 1,500 pounds per acre. In comparison, the North Columbia Basin of Washington and the Treasure Valley of Idaho, for example, average between 800 and 1,000 pounds per acre.
“So, we know the alkali bees are greatly improving the pollination,” Walsh says.
Spraying Solutions
Alkali bees used to be common throughout the Western United States.
Growers in the Walla Walla area have gone to great effort to protect their native bee populations. In recent years, new insecticides have been developed to fight lygus bugs while preserving the bees: Beleaf, or Flonicamid, and Sefina with Afidopyropen as the active ingredient.
“My research has found these to be relatively safe for bee populations when applied at night, certainly far safer than other broad-spectrum products that were used in the past, so I recommend those two during the earlier bloom cycles,” Walsh says. “Then at the end of the season, we have another product called Transform with the active ingredient sulfoxaflor, that is still relatively safe when following the mitigation efforts.”
That commitment could serve as an example to other growers who are concerned about protecting pollinators, but it’s not always a simple solution. While spraying at night is effective at protecting bees, it could put bats, moths, and other nighttime pollinators at risk, so it’s a balance.
“For these alfalfa seed growers, the bees are an investment, both the purchased leafcutter bees and the native alkali bees, and so if they aren’t taking care of them, they are really hurting themselves,” Walsh says.
Acreage Concerns
In recent years, reduced alfalfa acreage has coincided with a significant drop in bee populations. Walsh’s annual bee census shows how populations have fluctuated over the last decade.
From 2010 to 2021 the estimated population abundance of alkali bees varied from a low in 2021
of 1.6 million from the peak of over 9.4 million in 2012. In 2023, populations rebounded to 1.9 million bees in the original survey area, increased to 2.9 million when surveying additional areas.
“We had a huge glut of seed starting in 2017 but now all that surplus seed is gone. In 2017, I was down to about 700 acres. In 2024 I had 1,300 and then in 2025, I will have 1,700,” Wagoner says.
“In North America, we’re coming out of a long supply of inventory and alfalfa seed production is starting to ramp up again,” DLF vice president of field production Doug Gross says. “The estimates I’ve seen are that 2025 will see a five to 10% increase.”
In 2023, DLF acquired Corteva Agriscience’s global alfalfa germplasm and breeding program, including the company’s Hi-Salt salinity tolerant alfalfa, which DLF alfalfa breeder Steve Damon says may be suited perfectly for growers who rely on alkali bees.
“Our alfalfa breeding efforts prioritize drought and saline tolerance, and the Walla Walla area may be one of the best places in the world to do this research. We have a key research facility and team located in Touchet,” Damon says. “Our goals include pushing alfalfa to be productive in difficult environments where many other crops are unable to thrive.”
“This production region is unique; all the conditions are perfect for a very reliable alfalfa seed crop. The climate, soil, water supply and pollination support are ideal for alfalfa seed,” Gross says.
In the end, the success of Walla Walla’s alfalfa seed growers comes down to a partnership as old as agriculture itself — working in harmony with nature. The alkali bees, nurtured and protected by generations of farmers, are not just pollinators; they’re a cornerstone of the region’s resilience.
“It just works really well this way,” Wagoner says. “We didn’t have a single drop of rain from the third of June to about the 20th of September this last year. And that was perfect weather for the bees and perfect weather for the seed.”
