When entomologist Ed Show demonstrated a vacuumlike insect-sampling device to strawberry growers, several inquired about buying larger versions to clear whole fields. The reason: bugs are increasingly resistant to insecticides. Show and McCluney Manufacturing, in Watsonville, Calif., put together a tractor, vacuum, and fan to make the BugVac. The company says 50 will be sweeping 35% to 40% of northern California's strawberry fields this year.

-- Leslie Brokaw