Control of Slug in No-Till Corn, 1986

Abstract

Abstract No-till corn plots were located at Big Flats, NY. The soil is a Williamson silt loam, with a pH of 5.6 and 3.1% organic matter. The previous crop was conventional till 'Aroostook' rye (Secale cereale L.). The crop remained unharvested due to hail damage. The straw residue was left in place providing a very dense mulch. Quackgrass (Agropyron repens L. Beauv.), dandelions (Taraxacum officinale Weber) and miscellaneous broadleaf weeds were present in the field in early spring. On 18 Apr the no-till field was prepared by applying 2,4-D ester plus dicamba at 0.24 lb (AI) and 0.04 lb (AI)/acre respectively. Paraquat (0.5 lb (AI/acre) was applied ten days later. On 14 May a tractor drawn IH Cyclo Air Corn Planter was used to seed 4 rows at 30 inch spacing, 1 to 1.5 inches deep, and with seed drop of 27,400 kernels/acre. Furadan 15G were applied at 1 lb (AI)/acre and fertilizer (10-20-20) at 260 lb/acre at planting. Immediately after planting, metolachlor and atrazine were applied at 2.5 and 2 lb (AI)/acre respectively. The molluscicide treatments were replicated 6 times in a randomized complete block design. Plots were 20 × 20 ft contained 8 rows of corn, the outer two rows being untreated buffers. In each plot three holes, 4 inch diam × 6 inch deep, diagonally and evenly spaced, were excavated between rows with a golf-hole digger. Each hole was covered with a 1 ft-square asphalt shingle wrapped with aluminum foil. The reflective surface keeps the hole cool and moist, hence providing an ideal hiding place for slugs and serving as an efficient sampling method. Broot 15G was applied at seeding. Magnum plus Escort was applied as a seed treatment by evenly coating seed with Magnum, Escort and water. Mesurol bait was prepared by coating cracked corn with the wettable powder using soft drink as a sticking agent and applied at 20 lb bait/acre. Bait and spray treatments were applied on 30 May when the corn was at the 2-3 leaf stage. Slug damage to the corn plants was obvious. The molluscicidal baits were broadcast evenly by hand over the corn rows. Broot 50W was applied with a mechanical backpack sprayer at 50 gpa of water. On 19 Jun, ammonium nitrate (34-0-0) was sidedressed by hand to give 120 lb of nitrogen per acre. Slug counts were taken by inspecting the holes for live slugs at 2 days pretreatment and at 3, 7 and 14 days posttreatment. Corn damage ratings were taken by inspecting 20 corn plants per plot. Corn stand was evaluated on 20 Jun by taking two 1/1000 acre sample per plot (7.4 foot-row per sample).