Control of Spruce Spider Mite with Foliar-Applied Insecticides, 1996

A commercial nursery located in Weld County CO, was used as the site of the experiment. Plots were established on 5 Jul utilizing infested trees which were approximately 3 inch dbh and 6-8 ft tall. Experimental units were individual trees growing in furrow-irrigated rows. All treatments were applied using a hand-held compressed air sprayer to the point of run-off. A CR design with 5 replications was used. Plots were sampled on three subsequent dates by beat sampling. A white piece of 8 1/2 X 11 inch paper was held under the branch while each branch was struck 5 times with a short wooden stake. The number of mites dislodged and collected from the branches during sampling were subsequently counted. Four branches per tree (1 sample from each cardinal point) were taken on each date. Numbers presented represent the total number of mites per tree.