obtusely 3 to 5-angled in outline, and instead of the pit at inner angle and 

 the two conical projections on an excavated surface, has a convex surface 

 with two light-coloured distinct cones, one at the inner angle and the other 

 opposite beyond the middle of the area. This weed is abundant in western 

 Ontario and is troublesome in fields of fall wheat. It is a widely branching 

 biennial or winter annual with white flowers, and produces a large crop of 

 seeds, which ripen early. The seed is commonly found in poorly cleaned fall 

 wheat and rye and also in timothy, mammoth clover and alsike seeds. Land 

 is best cleaned by adopting a short rotation, including grain sown in spring 

 instead of in autumn. Plants which germinate in autumn can be destroyed 

 by fall or spring ploughing. 



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