A model of dryland cereal and oilseed production

Non-Peer Reviewe

Nitrate lost from various long-term fallow and continuous cropping rotations at Swift Current

Non-Peer Reviewe

An energy evaluation of crop rotations in southwestern Saskatchewan

Non-Peer Reviewe

Sod-seeding in the Aspen Parkland

Non-Peer Reviewe

Nitrogen management for yield and protein in wheat in the Brown Soil Zone

Non-Peer Reviewe

Rotation and fertility effects on root rot of spring wheat in southwest Saskatchewan

Non-Peer ReviewedSpring wheat grown in a replicated trial for one or two years after summerfallow, lentil, flax, or continuously (with and without fertilizer N) was examined for subcrown internode discoloration from 2000 to 2002 in southwest Saskatchewan. Discolored tissue was plated on nutrient agar for fungal identification. Root rot was in general present at highest levels in wheat grown after lentil, and at lowest levels in wheat grown continuously with low N fertility. The most common species were Cochliobolus sativus and Fusarium spp. Among the latter, F. avenaceum, F. equiseti and F. pseudograminearum were the most commonly isolated. F. avenaceum is the most important fusarium head blight (FHB) pathogen in western Saskatchewan. The percent isolation of Fusarium species was lowest in continuously-grown wheat with low N. Wheat after lentil had one of the highest levels of F. avenaceum. Among the crop rotations examined, it appears that the most favourable to the development of root rot in spring wheat was a wheat-lentil rotation. This rotation may also contribute to the build-up of F. avenaceum inoculum for the development of FHB, which is an important emerging disease of wheat and barley in western Saskatchewan

Rotations of wheat, barley, canola, and hay on a Dark Brown soil in west central Saskatchewan

Non-Peer ReviewedIn a long term study, yield of wheat or canola on summerfallow was influenced very little by rotation. On the other hand, yield of wheat or barley grown on stubble was affected by rotation. Yield of wheat on canola stubble was generally higher than on wheat stubble. Yield of hay was highly variable from year to year. Yield of canola relative to wheat was much higher during 1980 to 1991 than reported for 1972 to 1979. Further, yield variability of canola between years was much lower during 1980-91 than 1972-79. In wheat monoculture rotations, yield variability increased as summerfallow frequency decreased. In rotations of canola with cereals and/ or a forage the same trend did not occur. The influence of these results on economic viability of rotations where summerfallow is practiced less frequently is discussed

Moisture conservation and use at Swift Current – a comparison to previous findings

Non-Peer ReviewedThe results of an ongoing 18-year crop rotation study at Swift Current were compared to those reported 30-40 years earlier. The two periods showed no difference in over winter moisture conserved for stubble or fallow-systems. Moisture conserved in the 9 months (fall and winter) period on stubble was 34 % of the precipitation received in this period while 18 % of precipitation received in the 21 month fallow period was conserved. These compare w1th earlier reports for these two periods which were 33 and 21 %, respectively. The 18-year average moisture use efficiency for the current study averaged between 6.9 kg ha-1 mm-1 moisture used (mu) for fallow-seeded wheat and a low of 5.1 kg ha-1 mm-1 for continuous wheat that received P but no N fertilizer annually. Here mu was defined as spring soil moisture - Harvest soil moisture plus precipitation received from May 1 to August 31. These efficiencies for the more recent period were much higher than those reported by Staple and Lehane for the period of 1939-1950 where fallow wheat would produce 4.5 kg ha-1 mm-1 and stubble-wheat produce 3.7 kg ha-1 mm-1. The relationship between yield and mu for stubble crops was best described by a quadratic model while a linear model best fit the fallow crop data, The equation for the fallow system for the recent study was y = -397 + 8.69 mu (r=0.77**), while Staple and Lehane reported y = -1298 + 9.32 mu (r=0.83**). These equations suggest that the rate of increase per mm of mu are approximately the same for the two periods studied, but that in more recent times wheat is making more efficient use of smaller amounts of moisture. For example, while Staple and Lehane predict that 139 mm of moisture was required to produce 1 kg ha-1 of grain, we find that only 46 mm is now required for fallow-seeded wheat to produce 1 kg ha-1

The use of herbicides for brush control in pastures of east-central Saskatchewan

Non-Peer ReviewedOne of the main problems encountered with most methods of pasture improvement is the control of regrowth of young trees and shrubs which compete with grasses and legumes for moisture, nutrients, and sunlight. This paper reports on results from three timing experiments that used combinations of 2,4-D and dicamba and different patterns of herbicide application to control regrowth of woody plants in pastures of east-central Saskatchewan. The main woody plant species were aspen poplar, prickly rose, and western snowberry. The experiments were conducted during 1981 to 1989 in a community pasture located on a Waitville loam soil. The area had been cleared of trees and shrubs by bulldozing in the winter of 1979-80, prior to the start of the tests. In June of 1981 2,4-D ester or 2,4-D amine at 2.2 kg ha-1, plus dicamba at 1.5 kg ha-1, were foliar applied at full leaf expansion of the aspen poplar. Some treatments received repeated sprayings in the first year, second year, or in two consecutive years after the initial herbicide application. Other treatments studied included the application of 2,4-D tank mixtures with higher rates of dicamba, using a combination of fertilizer and herbicide, and using fertilizer alone. The results showed that herbicides were an effective method for controlling brush regrowth on pastures. The production of woody plant material was reduced by 52 to 98 %, while the production of grasses was increased nearly three-fold compared to untreated areas. When mixed with dicamba, application of 2,4-D ester was more effective for controlling undesirable plant species than the 2,4-D amine formulation. Using repeated herbicide applications improved the control of woody plants and improved the yields useable herbage. The highest yields of forage were obtained when herbicides and fertilizers were used in combination. Economic returns from brush control were generally highest for the one-time application of 2,4-D ester plus dicamba. Repeated herbicide applications, and application of a higher rate of dicamba, were not economically justified unless the value assigned to forage was very high. Under the conditions of this study, improving pasture productivity through application of fertilizer and herbicides in combination, or fertilizer alone, were less profitable than a one-time application of 2,4-D ester plus dicamba

Do irrigated companion oat crops reduce alfalfa yield and profits?

Non-Peer ReviewedEstablishment of 'Anchor' alfalfa with a companion oat crop was compared to direct-seeding the alfalfa on a sprinkler-irrigated site in 1982, 1983, and 1985. 'Beaver' alfalfa was added to the treatments in 1983 and 1985. An oat crop monoculture treatment was also included. Alfalfa-oat mixtures exhibited significant (P < 0.05) oat grain yield reductions of 9, 24, and 18 % in the three seeding years, respectively. Oat forage yields tended to be reduced in oat-alfalfa mixtures by 3, 12, and 8 %, respectively, but these reductions were not statistically significant (P > 0. 05). The forage yields of direct-seeded alfalfa were 26, 20 and 20 % higher (significant at P < 0.05) in the first production year (year following seeding) than oat-alfalfa mixture stands. In the second production year, yields were 22 % higher (P < 0.05) only in the 1982 seeding. Establishment method effects on stand density were significant (P < 0. 05) in the 1982 and 1983 seedings where the direct-seeded alfalfa had 50 and 25 % higher plant densities, respectively. Economic analysis of net returns per hectare indicated that the establishment method with the best returns varied among the three seedings years