Fall armyworm: Spodoptera frugiperda (J.E. Smith) FAW is the principal pest of sweet corn in southern Florida with larvae feeding successively in whorls, tassels, silks, and finally ears. Insecticides are sprayed frequently, especially after tassels have emerged, so new selective chemistries are needed to increase rotation options and minimize impact on beneficial arthropods. The trial was conducted at the Southwest Florida Research and Education Center in Immokalee Florida on 3 raised beds 32

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... nches wide and 420 ft long placed on 6 ft centers and covered with whiteface polyethylene mulch under which were placed two lines of drip irrigation tape with 4 inch emitter spacing. The center row remained untreated throughout the entire experiment for a buffer row and pest reservoir. Fertilizer (12-2-12) was mixed into the beds at 50 lbs N per acre and a 7-2-7 liquid fertilizer was injected through the drip using a Dosatron® during every irrigation cycle over the growing season. Corn was direct seeded 6 -Sep at 10-inch spacing with two seeds per hole. Four treatments were assigned in an RCB design across 4 replicates. Applications were made with a high clearance sprayer travelling at 2.3 mph equipped with ceramic Albuz ® ATR 80 "yellow" hollow cone tips each delivering 10 gpa at 180 psi. On 3, 6, 10, 13, 20, 24 Oct, one nozzle was placed overheard and one nozzle was located on each of two vertical booms (3 nozzles total). All other applications were made with two nozzles on each of the two drops (4 nozzles total) (Table 1) . Counts and damage assessments were made on 12 plants per plot noting the number of FAW larvae in the top of the whorl (4, 11 Oct), in the tassel (19, 25 Oct) and in the silk (1, 8 Nov) ( Table 2) . On 21 Nov the dominant ear of each of 20 plants per plot was harvested and evaluated, first rating the amount of visible damage to the husk based on the following scale: 0 = no damage, 1 = only silk damage, 2 = less than two penetration points, and 3 = 3 or more holes in husk. Husks were then removed and ears were graded into 4 categories; no damage, minor tip damage, kernel damage and significant tip and kernal damage (Table 3) . Data were subjected to ANOVA and means separated using LSD (P = 0.05). Both rates of Rimon and the standard rotation of Lannate/Warrior reduced larval numbers at all observations except for the first on 4 Oct. when fewer larvae were seen in the whorls only with the high rate of Rimon though not significantly different from the other two treatments. All sprayed treatments significantly reduced the amount of visible husk damage, increased the number of marketable (undamaged) ears and decreased the number ears with damaged tips and kernels compared to untreated plants.