Mobile fine sediment was caught in six screened pit traps installed in the bed of a cobble gravel channel. Sample periods lasted from several hours to several days, so the trapped material represents a good integration of the range of sizes in traction up to a limit near 10 mm imposed by the screens. All the traps, distributed along a bar, caught similar amounts of material, of similar texture. The peak transport rate for the <2‐mm fraction, corresponding with the lower portion of the bimodal bed material, was about 3 × 10−4 kg s−1 m−1. Observations continued for 6 weeks, through the nival flood on the stream. There was a sensible threshold for motion of material of all sizes, but minor transport occurred below it. Material up to 210 μm in size, including conventionally classified “wash” material, moved with near equal mobility over the season, but there were departures in individual sample periods. “Equal mobility” of fine material appears at best to be a statistical phenomenon which holds for a limited range of grain sizes over a seasonal period.

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Concentrations of Mo, Cu, Zn, Mn, Fe, N, Ca, P, Mg and K were determined in native and introduced grasses and legume forages from throughout northwestern Manitoba. Nutrient concentrations were compared with minimum requirements of cattle suggested by the Agricultural Research Council and the National Academy of Sciences–National Research Council. Differences in Mo concentrations were noted in forages between two geologic subareas within the study area. Cu and Mo concentrations suggested potentials for primary Cu deficiency in grasses throughout the region, and for Mo-induced Cu deficiency with grasses west of the Swan River formation and with legumes from all areas within the region. Throughout the study area, concentrations of Zn and Mn were found to be at deficient levels while those of Fe and Ca were found to be at adequate to excessive levels for cattel production. N and P concentrations in all forages were borderline to adequate, while Mg and K concentrations of grass forages were deficient to borderline with relation to the requirement of cattle.

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