Fall precipitation may have saved the day in Manitoba

WINNIPEG — An early fall snowstorm, followed by rain in the middle of October, recharged Manitoba soil at a time when it desperately needed water, says a provincial land management specialist.


Parts of Manitoba received 75 to 100 millimetres of badly needed moisture in October after several months of below average rainfall and scorching temperatures. 


Consequently, soil moisture conditions look much better than September, when many areas of Manitoba were excessively dry. 


“When you look at the maps that we have, some parts of the province had up to four inches of rain in October,” said Marla Riekman, who led the 2012 Manitoba soil moisture survey. 


She and her colleagues collected soil samples from 104 locations in the last week of October.


The survey data shows that most soil in the province was at 60 to 80 percent of water holding capacity going into freeze-up. However, there are areas where soil moisture is only 41 to 60 percent of water holding capacity, such as the southern Interlake and southwestern Manitoba. Moisture stress begins for most crops when moisture content drops below 50 percent.


“In general, we’re wetter to the north and a little bit drier to the south,” Riekman said during a break at the Manitoba Agronomists Conference held at the University of Manitoba Dec. 12-13. 


Survey data also indicates that most of the moisture is in the topsoil, while conditions are drier at lower regions of the soil profile. Riekman is still analyzing the profile data to understand what it all means.


What is known, however, is that the snow and rain in October may have prevented severely dry soil conditions next spring. Southern Manitoba received 50 to 80 percent of normal rainfall during the growing season. 


The summertime drought was particularly acute in southeastern Manitoba as water tables dropped, dugouts dried up and livestock producers were forced to feed cattle in July and August.


“They’re not fully saturated, but there is some moisture there again. Whether or not that is enough to fill dugouts again … I’m not quite sure yet,” Riekman said. “At least it’s something to help charge the system again.”