Fall Seeding Date and Species Effects on Spring Forage Yield of Winter Cereals

Abstract

A current research priority in short-season growing areas of Alberta is to increase cost efficiency of ruminant livestock production by extending the grazing season. The use of winter cereals is a potential source of earlier spring pasture than is provided by perennial grasses. This study determines the effect of fall seeding date on spring forage production of winter wheat (Triticum aestivum L.), fall rye (Secale cereale L.), and winter triticale (× Triticosecale Wittmack). One cultivar of each species (S) was seeded at Lacombe, AB, on 15 Aug., 1 Sept., and 15 Sept. in 1992 and 1993. Tiller and leaf numbers were recorded in the fall after dormancy. Spring clippings were taken when new growth was approximately 2 in. tall (as assessed by a disk height meter) and 1 wk later. Year and year × planting date effects were significant for most variables measured. Winter triticale and wheat were generally similar in treatment response while fall rye differed in some respects. Each delay of seeding resulted in smaller plants in the fall with fewer leaves and tillers. First clip yield varied from year to year, but was positively related to tiller or leaf number in the fall. Within the range of seeding dates used, earlier seeding produced earlier spring pasture. Fall rye tended to produce forage earlier and in greater quantity than the other two species. Dry matter yield generally increased linearly with increasing fall growing degree days (GDD) after planting. The use of early-planted fall rye for spring pasture in the western Parkland of the Canadian prairies is recommended. Research Question Alberta is a short-growing-season area where producers of ruminant livestock must feed conserved forage for 200 d or more each year. Extending the grazing season in spring or fall could have significant cost benefits for these producers. The feasibility of using spring-planted winter cereals either as monocrops or in mixtures with spring cereals has been demonstrated. It has been suggested that winter cereals may also provide alternative spring pasture to perennial grasses. The objective of this study was to determine the effects of seeding date on spring pasture production of three winter cereal species. Literature Summary Extension of the grazing season is a current research priority since significant cost savings to the livestock grazier can be effected. It has been shown that spring-planted winter cereals can be used to extend fall grazing and it has been suggested that fall-planted winter cereals may provide early spring pasture. Experiments relating to seeding date effects on winter cereals have confined observations to variables relating to grain production. It has been shown that optimum seeding dates differ for location according to climate and that deviation from this optimum, either earlier or later, generally results in yield reductions and some of the reasons have been explored. The effect of grazing on subsequent grain production has also been explored. There is little information on the effects of management practices on spring pasture production of winter cereals. Study Description This study was conducted for 2 yr at Lacombe, Alberta, Canada. Plots were seeded to ‘Norstar’ winter wheat, ‘Pika’ winter triticale, or ‘Muskateer’ fall rye on 15 August, 1 September, or 15 September each year. Fall observations included temperature and rainfall, time for crop emergence, and number of leaves and tillers produced per plant prior to winter dormancy. Spring weather records were kept from 1 April. The first clipping of plots occurred when crop canopy measured with a disk height meter was about 2 in. and a second followed 1 wk later. Herbage dry matter yields were determined. Crop growth stages, position of the growing point, and disk heights were recorded prior to each clipping. Applied Question Does seeding date for winter annual cereals affect spring pasture yield and earliness of usable pasture? Although year to year variations were large, earlier seeding generally produced higher yields and pasture was available earlier in the spring. Spring pasture yield showed a positive linear relationship to fall growing degree days. Do adapted winter cereal species differ in time and quantity of spring forage production or in response to fall seeding date? It appears that fall rye may have some advantage over winter triticale or winter wheat for spring forage production. In both years, rye produced harvestable forage earlier than the other two species. In one of the 2 yr, dry matter yields of rye were greater than the others. All species showed similar trends and relationships between seeding date and dry matter yield and harvest date. The growing point of rye remained below clipping height more consistently across clippings and seeding dates than the other species, which may allow a longer grazing period.