California Citrus Thrips Small Plot Trial, 1996

Insecticides were evaluated spring, 1996 in Field 12 (26 year-old ‘Atwood’ navel oranges) at the University of California’s Lindcove Field Station near Exeter, CA for control of citrus thrips. Pesticides were applied with a Bean hand-sprayer at 500 psi, outside coverage, approximately 200 gpa. Field 12 was divided into 4 contiguous blocks of 88-92 trees (22-23 replicates) and 22 treatments were applied with one replicate of each treatment assigned randomly to each block except extra replicates were assigned to the untreated check: each replicate consisted of four contiguous trees (except 2 replicates which had only 3 trees). Citrus thrips fruit scarring was evaluated early November. 1995 on all fruit on the exterior of data trees from knee to eye level. Scarring was rated as: (a) none, (b) slight (any citrus thrips scarring), or (c) severe (complete ring scar or extensive surface scarring at a level that would cause downgrading of fruit in a commercial operation). Approximately 5% severe scars are normally taken as economic scarring levels.