SECTION III 

 Plants Dangerous in Ground Feeds 



Many plants have poisonous seeds. Indeed in many 

 species there is a tendency for the poison to be collected 

 from other parts of the plant and concentrated in the 

 seed. These poisonous seeds are of great importance in 

 Canada, where they form a considerable proportion of 

 the screenings, millions of bushels of which are cleaned 

 from grain annually. It has been customary for millers 

 to mix the screenings from the wheat they grind, with 

 their bran and shorts. In the early days the screenings 

 obtained at the large grain elevators of the west were 

 destroyed, but of late years they also have been used in 

 the manufacture of feeds. This practice, which has been 

 fairly successful in the United States, has caused much 

 trouble in Canada, where the screenings on the average 

 contain a much larger proportion of poisonous seeds. The 

 loss from this source has been confined, for the most part, 

 to swine. Complaints have, however, come from men in 

 other branches of the livestock business, especially those 

 engaged in dairying, who claim that a great deal of 

 sporadic abortion has been caused by the use of feed con- 

 taining screenings. 



Much investigation into the character of our native 

 weed seeds is still needed, and it is probable that species 

 not now known to be harmful will be definitely proved so 

 in the future. This section gives a resume of the facts 

 BO far ascertained. 



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