b'The managed bee beds mimic desert habitats where the upwelling of springs resulted in salt accumulation and moist loca-tions for the bees to nest in, Walsh says.Pollinator PartnersWhile the alkali bees are important, alfalfa seed farmers else-where 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. Doug Gross, DLF vice presidentSteve Damon, DLF alfalfa Walsh has done some research using plastic mulch that couldof field production. breeder.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 theyve found 15 native bees in our area, but we dont know how to manage them yet, Wagoner says.He says its difficult to measure just which type of bee is the most important pollinator for the crop, because once the blos-som 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 exam-ple, average between 800 and 1,000 pounds per acre. So, we know the alkali bees are greatly improving the pol-lination, Walsh says.Mark Wagoner tends to the bees in the alfalfa stand.PHOTO COURTESY OF MARK WAGONERSpraying SolutionsAlkali bees used to be common throughout the Western United States.For these alfalfa seed growers, the bees are an investment, Growers in the Walla Walla area have gone to great effort toboth the purchased leafcutter bees and the native alkali bees, protect their native bee populations. In recent years, new insecti- and so if they arent taking care of them, they are really hurting cides have been developed to fight lygus bugs while preservingthemselves, Walsh says. the bees: Beleaf, or Flonicamid, and Sefina with Afidopyropen as the active ingredient.Acreage ConcernsMy research has found these to be relatively safe for beeIn recent years, reduced alfalfa acreage has coincided with a populations when applied at night, certainly far safer than othersignificant drop in bee populations. Walshs annual bee census broad-spectrum products that were used in the past, so I recom- shows how populations have fluctuated over the last decade. mend those two during the earlier bloom cycles, Walsh says.From 2010 to 2021 the estimated population abundance of Then at the end of the season, we have another product calledalkali bees varied from a low in 2021 of 1.6 million from the peak Transform with the active ingredient sulfoxaflor, that is still rela- of over 9.4 million in 2012. In 2023, populations rebounded to 1.9 tively safe when following the mitigation efforts. million bees in the original survey area, increased to 2.9 million That commitment could serve as an example to other grow- when surveying additional areas. ers who are concerned about protecting pollinators, but its notWe had a huge glut of seed starting in 2017 but now all that always a simple solution. While spraying at night is effective atsurplus seed is gone. In 2017, I was down to about 700 acres. In protecting bees, it could put bats, moths, and other nighttime2024 I had 1,300 and then in 2025, I will have 1,700, Wagoner pollinators at risk, so its a balance. says.26/ SEEDWORLD.COMFEBRUARY 2025'