Response of Bromegrass to N, P and S Fertilizer on a Gray Luvisolic Soil in Northwestern Saskatchewan

Abstract

Response of bromegrass to N, P and S fertilizer on a Gray Luvisolic soil in northwestern Saskatchewan. Can. J. Plant A 9-yr study was conducted on a Gray Luvisolic loam at Loon Lake, Saskatchewan to determine the effect of ammonium nitrate-N (34-0-0) and urea-N (46-0-0) on bromegrass (Bromus inermis Leyss.) production and nutrient quality, N recovery, and N use efficiency when the N was applied either annually or as a single application at the start of the experiment. The effects of phosphorus (P) and sulphur (S) were also assessed. Each N source was applied at single rates of 0, 100, 200, 4OO and 800 kg ha-'N and annual rates of 0, 50, 100 and 200 kg hs-t N. The ammonium nirrate was also applied as a single dose at rates of600 and 1000 kg ha-rN. Phosphorus and S were applied every second year at224 kg ha-t PrO, and 45 kg ha-t S. Forage dry matter yields were positively related to precipitation received in May and July, and April-May, but negatively related to June precipitation. Forage dry matter production was greater over the first 8-yr period for annual N applications than for a single application receiving an equivalent amount of N; but fertilizer N recovered in forage over the same period was similar (about 30%) for the two methods of application. Dry matter yields were 19% greater after 4 yr and 26% greater after 8 yr when ammonium nitrate was used compared to urea. Recovery of fertilizer N in forage also favored the ammonium nitrate source. The application of low to moderate N rates depressed forage N and P concentrations when yield response was high but concentrations were tncreased by the highest rates of N fertilizer and by repeated annual applications of N. Toxic concentrations of NO,-N occurred in bromegrass in the first year when N was applied at or above 400 kg ha-las one application and also in the second year when N was applied at 800 kg ha-l. When N was applied annually at 200 kg ha-r, NO,-toxicity became a potential problem in later years as soil mineral N accumulated. Phosphorus and S fertilizers increased dry matter yields of forage; P fertilizer increased and S decreased forage P concentration. Annual N applications resulted in more uniform year-to-year yields and N uptake response compared to a single application and provided greater dry matter production without loss of nutritive quality. It was concluded that, in contrast to reports in the literature, the response of forage grasses to N is not site specific.

Effect of N fertilizer on the productivity and nutritive values of perennial grass mixtures in the alpine region of Qinghai-Tibetan Plateau, China

“…Similar results of increased NUE with increasing N application rate obtained from the studies on bromegrass and other perennial grasses by other researchers (Ukrainetz et al 1988;Penney et al 1990;Harapiak et al 1992) support this finding. This fact implies that some amount of N fertilizer at higher application levels either remained as residues or was wasted in perennial grass pasture.…”

The influence of harvest management and fertilizers on herbage yields of cool-season grasses grown in the Aspen Parkland of northeastern Saskatchewan

“…The forage production of cultivars is affected by the genetic ability of the cultivars to compete with other species (Knowles et al 1987, McCartney andBittman 1994), the nutrient status of the soil, available soil moisture (Simons et al 1985;Ukrainetz et al 1988;Nuttall et al 1991) and the cutting and pasture management used to harvest the crop. With this series of experiments on two contrasting soils in northeastern Saskatchewan, we are able to discuss, in detail, the effect of harvest management on cultivar yields.…”

Current and residual effects of nitrogen fertilizer applied to grass pasture on production of beef cattle in central Saskatchewan

“…was the first cultivar of crested wheatgrass released for use on the Canadian Prairies in 1932 and since then it has become widely naturalized in its areas of adaptation (Rogler and Lorenz 1983). There have been several reports on the benefits of adding nitrogen fertilizer to crested wheatgrass and other grass pastures (Lawrence et al 1982;Campbell et al 1986; Ukrainetz and Campbell 1988;Ukrainetz et al 1988) in Saskatchewan yet very little fertilizer is applied to the 19.4 million ha of pasture on the Canadian Prairies even though the practice has been reported to be economically beneficial (Holt and Zentner 1985;Zentner et al 1989). This may be because North American farmers tend to manage animals so that additional forage resulting from fertilization is underutilized (Beaton and Berger 1974).…”