Location: Pollinating Insect-Biology, Management, Systematics Research
Project Number: 2080-30500-001-048-A
Project Type: Cooperative Agreement
Start Date: Apr 1, 2026
End Date: Jun 30, 2027
Objective:
Objective: Determine an optimal time for residues of isocycloseram to degrade to minimize impacts on emerging alfalfa leafcutting and endemic bees at the farm scale. For alfalfa seed production, Integrated Pest and Pollinator Management Program at WSU completed field efficacy and laboratory bioassay studies against Lygus bugs and spider mites with a new chemistry called isocycloseram. This pesticide appears to effectively control both pests. Learning how this pesticide persists in the field to affect bee pollinators that are critical for seed production is essential for developing best management plans for its use.
Approach:
1. Field plots of 20 acres of alfalfa seed crops will be treated 3, 2 , or 1 week before bee emergence (alkali bees and alfalfa leafcutting bees). Plots will be compared to plots treated using present treatments and plots treated with sulfloxaflor.
2. Plots will be monitored for lygus bugs of different states, alfalfa weevils. In addition measures of beneficial insects and spiders will be made.
3. Impact on bees will be evaluated using alfalfa leafcutting bees and their nesting (reflective of pollination and bee reproduction). In collaboration with Dr. Kelsey Graham, the number of nest cells, fate of larvae, and overall success will be determined using X-rays. Impact on endemic bees (other species) will be evaluated using bowl traps. Bees will be identified and quantified to determine the impacts on the total bee populations available in the different plots.