Lygus spp. are major pests of the California strawberry industry and have prompted growers to purchase and use machines called "bug vacuums" to mitigate damage throughout the production season. The aim of this work was to design, develop and evaluate a vacuum to mechanically remove and eliminate Lygus spp. from California strawberry fields at higher rates than existing vacuum systems. Field tests of the prototype vacuum were conducted in Guadalupe, California on raised strawberry beds with fully developed canopies. Results indicated that the prototype vacuum significantly increased removal of Lygus spp. compared with a conventional vacuum. The average number of Lygus spp. removed on each pass by the prototype vacuum was 2.2 times greater than that of the conventional vacuum. The use of cylindrical ducts and two fans per bed increased airflow and resultant Lygus spp. removal. The elimination baffle located at the outlet of the conventional vacuum was observed to significantly reduce air speed and raising it 30.2 cm above the outlet increased air speed by 17% (3.0 m/s) at the vacuum inlet. A validation study of a computational fluid dynamics model suggested that simulations could serve as a useful tool for bug vacuum design.

Six prodiamine treatments, three applied alone and three applied in combination with methazole, were compared with oxyfluorfen/oryzalin, oxadiazon, and controls (weeded and non-weeded) on ornamental and weed species. Ornamentals included green liriope, Asiatic jasmine, serissa, gardenia, `Needlepoint' holly, Japanese yew, `Prostrata' juniper, and `Carror' azalea. Weeds grown in separate containers were goosegrass, crabgrass, pigweed, and prostrate spurge. At 13 days after treatment (DAT), oxadiazon and oxyfluorfen/oryzalin caused some contact burn on liriope, and the injury persisted until the 81 DAT rating. Methazole/prodiamine treatments caused chlorosis on gardenia leaf tips, with plants recovering by 61 DAT. These combinations also resulted in slight injury to azalea at the first rating, but the injury disappeared by the second rating. Control of goosegrass, crabgrass, and pigweed was good to excellent with all chemical treatments. Control of spurge using oxadiazon and oxyfluorfen/oryzalin decreased at 81 and 100 DAT.

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