Western corn rootworm (WCR): Diabrotica virgifera virgifera LeConte Northern corn rootworm (NCR): Diabrotica barberi Smith and Lawrence A trial was established to evaluate liquids, granules and seed-applied insecticides for their efficacy against corn rootworm larvae. The trial was conducted at the OARDC Western Agricultural Research Station near South Charleston, Ohio. Corn was planted with a two row John Deere 7000 MaxEmerge planter set to plant 30,200 seeds per acre on 2 May. The trial was

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... anted in an area that was in late-planted field corn in 2006. The granular and liquid insecticides were applied at planting to four rows (30 inch spacing) by 60 ft long plots arranged in a RCBD with four replicates per plot. All of the insecticide treatments were applied to the corn hybrid Dekalb DKC61-73 (RR2/YGCB). Three granular insecticides (Aztec 2.1G, Force 3G and Lorsban 15G) were applied T-banded (TB) with a modified Noble applicator that was calibrated to deliver the desired rate. Four granular insecticides (Aztec 4.67G, Counter 15G, Fortress 5G and Lorsban 15G) were applied either in-furrow (IF) or T-banded with a SmartBox metering system calibrated to deliver the desired rate. The liquid insecticides Capture LFR, Force CS and Lorsban 4E were applied as a TB with a CO 2 sprayer using a TeeJet 80067 nozzle calibrated to deliver 5 gal/acre. The seed treatment insecticides Cruiser 1250 and Poncho 1250 were commercially applied to the seed before planting. Rootworm feeding injury was evaluated in all trials by randomly digging 5 roots per replicate for each treatment. Roots were washed, examined for corn rootworm larval feeding injury and rated in accordance with the 0-3 Node Injury Scale. Stand counts were made by counting the number of plants in 25 ft of the two center rows and then converting those counts to plants per acre. Yields were determined by machine harvesting the two center rows of each plot and converting the grain weights to bushels per acre at 15% moisture. Data were analyzed with ANOVA and means separated using LSD at the 5% level. There were statistical differences in root ratings but root injury from corn rootworm larvae was very light in this trial. There were no statistical differences in either stand or yield among the treatments.