Subsoiling for soil and water conservation

Non-Peer Reviewe

Effects of summerfallow flax and mustard barrier strips on the subsequent crop

Non-Peer Reviewe

Grass barriers for wheat production in southwest Saskatchewan

Non-Peer ReviewedWind has long been considered a bane to farming in the Brown and Dark Brown Soil Zones of southwest Saskatchewan. Blowing dust from rampant wind erosion in an all-too-often occurrence. Strong hot summer winds cause tremendous moisture stress to crops – particularly in dry years when crops are already drought-stressed. Perennial vegetative windbreaks have been advocated as a way to reduce near-surface windspeeds both to control wind erosion and to improve crop yields through better water conservation and decreased in-crop evaporative stress

Measurement of water use by canola with sap flow gauges

Non-Peer Reviewe

Comparison of a spring wheat-mechanical fallow rotation with a winter wheat-chemical fallow rotation in southwestern Saskatchewan

Non-Peer ReviewedA Canuck spring wheat-mechanical tillage fallow rotation (SWMF) was compared to a Norstar winter wheat-chemical fallow rotation (WWCF) between 1981 and 1985 at Swift Current. Over the 5 year period, production costs were somewhat greater for SWMF but grain yields, gross returns, and net returns were not significantly different between rotations. Yearly variation in grain yields and net returns were less for WWCF. In the wetter years of 1981, 1982, and 1983, SWMF had significantly larger grain yields, gross returns, production costs, and net returns. In the drier years of 1984 and 1985, production costs were similar but WWCF had significantly larger grain yields, gross returns, and net returns. Total herbicide costs for both rotations were essentially equal. Available soil water in the spring of the crop year was equal for the two rotations which suggested WWCF had less non-productive loss of water

Yield adjustment by canola under different plant populations in the semiarid prairie

Non-Peer Reviewe

Optimum strategies for mapping management zones using temporal remote sensing information

Non-Peer ReviewedTechnological advances in variable rate application and global positioning systems (GPS) make site-specific management technically feasible. No longer do fertilizer and pesticides need to be applied uniformly across a field, they may be varied to match the soil productivity across the field. However, successful site-specific management depends on identifying management zones and the determining optimum input application rate for those zones Unfortunately, identifying management zones that are reasonably consistent from year to year has been the greatest problem to successful site-specific management. In this study we found that crop vigor measured with normalized difference vegetation index (NDVI) based on satellite (LANDSAT) remote sensing for two different years was successful for identifying management zones. Based on the NDVI, we divided a field near Shaunavon in southwestern Saskatchewan into two zones: zone 1 with low crop and vigor zone 2 with high crop vigor. The zones corresponded to differences in soils, particularly, soil moisture, but it would be too costly and impractical to try to delineate these zones from detailed soil sampling. Wheat yield and protein were more responsive to N in zone 1 than in zone 2. The optimal N fertilizer rate was 95 kg/ha for zone 1 and 75 kg/ha for zone 2. Satellite remote sensing is a cost-effective method to delineate management zones for site-specific management

Stubble and seeding management to improve microclimate and seed yield of canola

Non-Peer ReviewedThe benefit of standing stubble for wheat and pulse growth and yield is dependent upon the height of the stubble. Taller stubble traps more snow and creates a better microclimate for seedlings growth than short or cultivated stubble. Since information on the effect of stubble management on the in-crop microclimate of canola was lacking, a three year field study was conducted at Swift Current. Short (15cm) and tall stubble (30cm) effect on microclimate and seed yield were compared with that of cultivated stubble. The microclimate parameters included wind velocity, soil, air, and plant temperatures, solar radiation, and relative humidity. Microclimate observations indicated lower wind speed near the soil surface and lower soil temperatures in tall compared to cultivated stubble. Surprisingly, the stem temperature of canola seeded in tall stubble was higher than cultivated stubble. Biomass production and water use efficiency increased for tall standing stubble compared to cultivated stubble. Tall stubble increased mean seed yield by 9 and 19% compared to short and fall cultivated plots, respectively. The results indicated that a combination of improved microclimate was responsible for the yield increase

Yield and protein of wheat and durum in Brown Soil Zone as affected by long-term tillage system and crop rotation

Non-Peer ReviewedThree tillage-rotation experiments in the Brown soil zone showed that spring wheat and durum grain yield and protein were affected by tillage system, length of time in tillage system, crop sequence. During the initial 15 years of no-tillage (NT) monoculture wheat, grain yield and protein were equal or lower than minimum-till (MT) or conventional tillage (CT). These differences were attributed to reduced N availability with NT, likely from greater N immobilization (sequestration) in soil organic matter under NT. However, during the last several years, grain yield and protein with NT continuous wheat has been equal to higher than with MT practices. This may be due to improved management, specifically better control of foxtail barley and side banding of N at time of seeding, and/or simply a longer time in NT. When following non-cereal crop, spring wheat and durum had equal or higher yield and protein than wheat following wheat. In diversified rotations, the wheat or durum had highest yield under NT practices. Wheat on MT and NT fallow, with an extra 23 kg/ha fertilizer N applied, had higher grain protein than wheat on CT fallow but not higher grain yield. Durum grown on fallow after a pulse crop had higher yield and protein than that grown after fallow after durum

A simple model for quantifying change in soil organic C as influenced by tillage and crop rotations on the Canadian prairies

Non-Peer ReviewedSimulation models are required for quantifying the impact of crop rotations and tillage on soil organic C dynamics, and for aggregating C sequestration over a relatively large area. However, most current models of soil organic C have been built based on kinetically defined discrete pools with different turnover times. Those pools of soil organic C only exist conceptually. They have not been determined experimentally, thus validation of kinetic models describing soil organic C turnover is usually difficult or not independent from actual measurements. Thus, there is a need to develop a simulation model that can be easily validated and used for estimating future projection of C sequestration under specified management practices. A simple model has been developed to quantify the impact of crop rotations and tillage on soil organic C and validated using long-term field experiments conducted on the Canadian prairies. This simple model required a few input parameters and accurately predicted the change of soil organic C with a relative error of 5% or better. Crop rotation in cereal-dominant cropping systems, affected the amount of soil organic C due to differences in the amount of crop residue inputs. Clay content of soil played a vital role in determining the soil organic C sequestered under conservation tillage compared to tilled systems. This study also showed that the rate constant of soil organic C turnover was about the same for all systems in the drier region of the Canadian prairies, regardless of soil texture and the cropping system