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Rijal said. "We did some trials earlier this year with some new insecticides and we'll have more information about these later in the year." Research ongoing for improved LFB monitoring For LFB, best monitoring protocols are available, but often point out damage after it's too late to act. A multiyear effort led by UC Riverside Entomology Professor Jocelyn Millar — and funded by the Almond Board of California — has worked to improve the monitoring options for the pest. "You can take beat samples of the crop canopy to look for adults or nymphs, but we've never established any kind of treatment threshold for that practice," said Houston Wilson, assistant cooperative extension specialist in the Department of Entomology at UC Riverside and collaborator on the project. "Identifying gummosis is easier because you can look for the signs of feeding, but it's an artifact — by the time you see it, the leaffooted bug has already damaged the nuts." A passive sampling system for leaffooted bug, like for navel orangeworm, where a pheromone attracts the insect to a trap doesn't exist — yet. Over the past five years, Millar and his team have been identifying compounds that make up the leaffooted bug pheromone. Nine compounds were identified, with the last compound identified entirely new to science. Millar noted this new compound was a relatively small part of the overall pheromone composition but it packed the biggest punch, triggering the strongest responses from the bugs. Over the last two years, Millar's team has been able to collect enough material to identify the compound and synthesize it. At the same time as the pheromone work, the team at UC Riverside — and other collaborators such as Cooperative Extension Specialist Kent Daane — began looking at the best trap for the application. They tested multiple styles of traps and colors, ultimately identifying that a hanging cross-vane panel trap coated with a sticky substance — yellow or blue in color — performed the best for trapping leaffooted bug. With a fully recreated pheromone and an effective trap, the team ran trials in commercial almond, pistachio and pomegranate orchards in the Central Valley. Based on trials, the team concluded the trap and pheromone were effective and will look to the private sector to commercialize the new monitoring system. The Almond Board encourages growers to consult with their trusted PCA to determine monitoring and treatment protocols specific to their operations. More information about best management practices of leaffooted bug and brown marmorated stink bug is available at the UC Statewide IPM website. 1 ALMOND ORCHARD 2025 GOAL Spotting the Difference! Hatched Leaffooted Bug Eggs 1 UC IPM website: ipm.ucanr.edu/agriculture/almond Brown Marmorated Stink Bug • Clusters of 28 eggs • Can produce 480 eggs in their lifetime • Multiple gumming spots per nut • Damage is more common in May and June Leaffooted Bug • Strands of 10–15 eggs • Can lay more than 200 eggs in the first two months of spring • One or two spots per nut, resulting in thread-like gumming • Damage occurs in March and April Gumming excreted from almond hulls, a sign of plant bug damage. Courtesy: Jhalendra Rijal, UCCE Growers can learn more about brown spot, true bugs and the research developments at The Almond Conference 2022. REGISTER TODAY Almonds.com/Conference Almond Board of California 4

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