Residue management increases seed yield of three turfgrass species on the Canadian prairies

Abstract

. 2002. Residue management increases seed yield of three turfgrass species on the Canadian prairies. Can. J. Plant Sci. 82: 687-692. Little information is available on the management of turfgrass species for seed production in the Canadian prairies. The objective of these studies was to assess the impact of residue management and row spacing on seed yield under irrigation. A factorial experiment was seeded at Saskatoon, SK, in 1993 to assess the impact of burning or scalping (very close mowing with residue removal) vs. mowing, and 20-vs. 40-cm row spacing on seed yield of Kentucky bluegrass (KBG) (Poa pratensis), creeping red fescue (CRF) (Festuca rubra subsp. rubra) and creeping bentgrass (CBG) (Agrostis palustris). Also, a residue management trial on KBG was seeded at Brooks, AB, in 1993. At Saskatoon, yield was higher at 20-cm spacing across all three species in 1994, but spacing had no impact on winter survival, stand density, tiller growth or yield in subsequent years. Burning and scalping consistently resulted in earlier spring green-up, a higher proportion of fertile tillers, and higher seed yield than mowing. Even with residue management, yield declined after one harvest in CBG and CRF, and after two harvests in KBG. At Brooks, residue management had a similar impact on yield of KBG. A second trial at Brooks examined the impact of row spacing (20, 40, 60 cm) and seeding rate (0.5 to 6 kg seed ha -1 ) on KBG. Seed yield was highest at 40-cm spacings in 1994, at 60 cm in 1995, and at 40 to 60 cm in 1996. Seeding rate did not have a consistent effect on yield. We conclude that a combination of residue management and 20-to 40-cm spacings provide the highest, most consistent seed yields for these turfgrass species in this region. On sait peu de choses sur la culture des herbes à gazon pour la production grainière dans les Prairies canadiennes. L'étude que voici devait servir à évaluer l'incidence de la gestion des résidus et de l'espacement des rangs sur le rendement grainier des cultures irriguées. En 1993, les auteurs ont procédé à des semis factoriels à Saskatoon (Sask.) pour déterminer les effets du brûlage ou du scalpage (tonte au ras du sol avec élimination des résidus) comparativement à ceux de la tonte, et l'incidence d'un espacement de 20 cm plutôt que de 40 cm sur le rendement grainier du pâturin des prés (PP) (Poa pratensis), de la fétuque rouge traçante (FRT) (Festuca rubra sous-esp. rubra) et de l'agrostis stolonifère (AS) (Agrostis palustris). Ils ont aussi procédé à un essai de gestion des résidus sur PP à Brooks (Alb.), la même année. À Saskatoon, en 1994, les trois espèces ont enregistré un meilleur rendement grainier avec un espacement de 20 cm, mais l'écartement n'a eu aucune répercussion sur la résistance à l'hiver, la densité du peuplement, le tallage et le rendement des années subséquentes. Le brûlage et le scalpage entraînent toujours une repousse plus rapide au printemps, une hausse de la proportion de talles fertiles et un meilleur rendement grainier que la tonte. Même avec la gestion...

Phytophagous arthropods and silvertop levels associated with post-harvest residue treatments in three turfgrass species grown for seed

“…As the stand matured and inter-row spaces filled in, row spacing ceased to have an impact. In the agronomy portion of this study, the effects of row spacing on grass stand density, spring green-up, and plant growth stage in early spring were also short-lived (Gossen et al 2002).…”

“…In 1994, the year after establishment, CBG stands were lush and thick. In 1995 CBG had less ground cover and spring green-up than the other two species because of severe winterkill (Gossen et al 2002), but recovered in 1996, resulting in a moderately vigorous stand. In May of 1994, early in the life of the stand, the highest numbers of arthropods occurred in the 20-cm row spacing.…”

“…The biggest difference was the dramatic increase in seed heads of CBG in 1996 (Table 5). From almost no seed yield in 1995, CBG recovered to produce a seed crop exceeding 100 kg ha -1 in 1996 (see Gossen et al 2002). In both years KBG had the highest proportion of reproductive tillers, although CBG had similar levels in 1996.…”

“…National (CBG), were seeded under irrigation in 1993 at the Agriculture and Agri-Food Canada research farm at Saskatoon (52°07′N, 106°35′W) in a Sutherland clay-loam soil at rates of 2, 2, and 3 kg ha -1 , respectively. Details of the design, maintenance, and results of agronomic assessment of the study are reported in Gossen et al (2002). Plots 3.6 × 22 m in size were seeded in 20-or 40-cm row spacings in a split plot design such that grass species were arranged as main plots and row spacings as sub-plots.…”

“…The objectives of this study were to assess (1) the arthropod populations in a turfgrass seed trial in western Canada to determine if there was an association between these populations and silvertop seed head injury; (2) the impact of different residue management programs on arthropod populations and silvertop incidence, and (3) the impact of silvertop on grass seed yield. The results of the agronomic studies on grass survival, growth, and seed yield from this trial were published earlier (Gossen et al 2002).…”