Pear, Lime-Sulfur Timing Study, 1992

The purpose of the trial was to compare effectiveness of lime-sulfur plus oil treatments when applied post-harvest (PH), post-harvest plus delayed dormant (PH + DD), or delayed dormant (DD). Plots of mature Bartlett trees, 0.5 ha in size were replicated 3 times in a randomized block design. Lime-sulfur was applied at the rate of 112.2 liter/ha and combined with oil at 37.4 liter/ha. PH applications were made on 16 Oct at 1870.5 liter/ha and the DD application were made 24 & 25 Feb at 1143.5 liter/ha. All treatments were made using conventional air-carrier equipment. An additional spray applied to the entire orchard was 56.1 liters/ha Orchex 796 spray oil applied on 5 Feb. Samples were made biweekly by randomly selecting 10 fruit buds or clusters per replicate and counting PP (eggs and nymphs) and TSSM (eggs and immatures) with the aid of a dissecting microscope. Adult PP were counted from 5-beating-tray samples per replicate.