In 1997 and 1998 corn (Pioneer 3211 and Pioneer 3751, respectively) was planted in 150 m long, six-row plots on Portneuf silt loam soil (coarse-silty, mixed, superactive mesic Durinodic Xeric Haplocalcid). Plots were sloped 1.5% and every other furrow was a wheel tracked furrow used for irrigation. Plots were furrow irrigated approximately every ten to 14 days with either 1) untreated canal water, 2) water containing 10 ppm PAM during initial advance (NRCS std), or 3) water treated with PAM by placing 35 g of granular PAM along one meter of furrow prior to initiating irrigation (patch method). Herbicide treatments were either 1) controls, 2) Eradicane (EPTC), or 3) Dual II (Metolachlor). Herbicides were spray-applied and preplant incorporated at label recommended rates. Plots were in a randomized split plot design with herbicide treatment main plots and PAM treatment subplots. Inflow was regulated at each furrow inlet. Runoff was monitored using small, individual furrow, calibrated flumes. Infiltration was determined by inflow-outflow difference. Sediment concentration was determined from one liter samples collected periodically from each furrow and allowed to settle in Imhoff cones. Imhoff cone sediment volumes were calibrated against mass concentration determined from filtration of a subset of samples. Sediment loss was determined by multiplying outflow volume by outflow concentration. Weed seed losses were determined in separate subsamples. Weed seedling stand was determined by counting and typing seedlings 7.5 cm to either side of two-meter sections of furrow at three points in the field. Forage yeild was measured on two three-meter harvest-row samples, one from the upper and one from the lower half of each plot.
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| [Title] [Abstract] [Approach] [Table 1] [Table 2] [Table 3] [Table 4] [Conclusions] | |