Why are tame hay yields declining in Saskatchewan?
Provincial agricultural production statistics show that grain crop yields have generally increased over the past 35 years while tame hay yields peaked in 1980 and have since been in decline. Weather data from 16 sites across Saskatchewan for the April, May, and June (AMJ) period were examined to explain this decline. As expected, precipitation during AMJ was positively correlated to hay yield but temperature was not. Hay yield was subsequently expressed as water use efficiency (WUE) based on published annual mean hay yield and AMJ precipitation. The WUE exhibited a negative correlation to year since 1980 and to the harvested hay acreage per year. After de-trending both WUE and harvested hay acreage for the year effect, the residual variation in both variables was still negatively correlated. We propose that older and lower-yielding hay fields are being harvested more frequently over the last two decades to provide feed for a growing Saskatchewan beef cow herd. This suggests that forage extension efforts should focus on hay field rejuvenation and agronomic management for improved productivity.
water use efficiency
The following license files are associated with this item: