ALBERT

Description: A two-year field study was carried out to determine whether inoculating white spruce, Picea glauca (Moench) Voss, with a native endophytic fungus, Phialocephala scopiformis DAOM 229536 Kowalski & Kehr (Helotiales, Ascomycota), decreased the performance of eastern spruce budworm, Choristoneura fumiferana Clemens, developing on these trees. Second instars were reared at three densities in the mid crown and at one density in the lower, mid, and upper crown. Larval survival (i.e., survival of larvae to pupation) was lower on endophyte-inoculated trees than on control trees in the mid crown and especially the upper crown but was similar in the lower crown, resulting in a significant interaction between endophyte and crown level. A similar but marginally insignificant interaction was observed for overall survival up to adult emergence (i.e., total survival). Larval survival and total survival were approximately 22% and 19% lower, respectively, when developing in the upper crown of endophyte-inoculated trees than in control trees. Larval survival remained relatively constant, with increased density on control trees but decreased with density on endophyte-inoculated trees, resulting in a significant interaction between endophyte and larval density. Sex ratios of emerged adults and wing lengths of emerged females were not influenced by the endophyte. Our results suggest that endophytic fungi could be useful additions to integrated pest management programs.

Description: Miller, J. J., Curtis, T., Chanasyk, D. S. and Reedyk, S. 2015. Influence of mowing and narrow grass buffer widths on reductions in sediment, nutrients, and bacteria in surface runoff. Can. J. Soil Sci. 95: 139–151. Little research has been conducted on the effect of mowing and buffer width on the effectiveness of short-width (〈 10 m) native grass buffers to filter sediment, nutrients, and bacteria. A 2-yr (2011–2012) field study was conducted on native rangeland in southern Alberta. The treatments of mowing and buffer width (1.5, 3, 6 m) were evaluated using a randomized complete block design with four replicates. The buffer plots were pre-wet with distilled water. A spiked solution was then applied to each plot using a run-on distribution device and the runoff collected every 10 min for 30 min once the runoff started discharging from the plot. The volume of runoff, and percent reduction in concentration and mass of sediment [total dissolved solids (TSS)], phosphorus [dissolved reactive P (DRP), total P], nitrogen (total N), and bacteria (Escherichia coli, total coliforms) in runoff were determined. The findings did not support our hypothesis that percent reductions in concentrations and mass for sediment, nutrients, and bacteria were greater for mowed than unmowed buffers. In contrast, the findings supported our hypothesis that increasing buffer width would significantly (P≤0.05) decrease mass (but not concentration) of sediment, nutrients, and bacteria in runoff. The significant mass reduction was attributed to a reduced runoff ratio caused by longer residence time and greater infiltration in the wider buffers. Mass reductions for the three buffer widths ranged from 29 to 92% for TSS, 22 to 93% for DRP, 38 to 93% for total P, 23 to 92% for total N, and between 61 and 94% for E. coli and total coliforms. These findings suggest that buffer width but not mowing may reduce runoff quantity and improve runoff quality over the short term.

Description: Miller, J. J. and Chanasyk, A. S. 2015. Unsaturated water flux at mid and lower slope positions within an inclined landscape of the Dark Brown soil zone in southern Alberta. Can. J. Soil Sci. 95: 27–36. Little research has quantified vertical-unsaturated water flux below the root zone for mid and lower slope positions within inclined, low-relief, and longer-slope landscapes of the Dark Brown soil zone of the Canadian prairies. We measured soil moisture (0.23–1.22 m) in the field at mid and lower slope positions in southern Alberta from May to October in 1985 and 1986. Undisturbed soil cores were taken from soil horizons and saturated hydraulic conductivity and soil moisture retention were determined in the laboratory. Vertical-unsaturated water flux below the root zone was calculated between 1.07 and 1.22 m depths below ground surface using the hydraulic gradient method. Water fluxes for the 2 yr ranged from