22 



THE ROYAL SOCIETY OF CANADA 



The winter of 1916-17 was very severe; the temperature dropped 

 to below zero in the first week of December and the cold spell lasted 

 without a break until the second week in March. On December 

 13th the soil was protected by a covering of snow averaging 13 inches 

 in depth and the temperature at a depth of 1 foot was 38 • 5° F. Very 

 high winds influenced the depth of snow, and some fields were exposed 

 to a cold of — 17°F. practically without a snow covering. On the other 

 hand fields which had a good covering of loose snow from the very 

 first were well protected against the cold weather. The snow layer 

 gained steadily in thickness, reaching a depth of more than 3 feet at 

 the beginning of March, and many spots were found to be practically 

 free from frost. In March although the weather moderated consider- 

 ably the frost penetrated more easily through the packed snow and the 

 frost line in most placed descended six to twenty inches. 



In spite of the continued severe frost the soil in Quebec is so well 

 protected by the heavy snowfall that the frost as a rule cannot pene- 

 trate very far, perhaps less than in places further south where any 

 snowfall usually melts away during the periodical thaws. Farther 

 West, in Manitoba and Saskatchewan, the severe winter cold acts 

 on a practically bare ground and will penetrate several feet. 



Soil Temperatures. 

 Winter 1916-17. 



The soil temperatures were taken with three standard soil thermo- 

 meters. Two, one foot and three feet in length, were placed close 



