152 Weeds. 



they are quite easily removed from wheat 

 and barley by screening. They are more 

 difficult to take out of seed oats, as a small 

 proportion will stick in the crease of the 

 larger oat grains. They are exceedingly 

 difficult to remove from the seeds of clover 

 and alfalfa, however, as they are about the 

 same size and shape as the seeds of these 

 plants. Care should be taken in purchas- 

 ing clover and grass seeds to see that they 

 are free from seeds of these and other 

 weeds. 



2. Harrozviiig spving-soivn small grain 

 fields in the early spring, when the young 

 grain begins to appear, and again when it 

 is about three to five inches high, is quite 

 effective in killing the young mustard and 

 similar plants. In some instances three 

 and even four harro wings may be given, 

 especially in areas where the grain also 

 will be benefited by harrowing it thus fre- 

 quently. This method can only be prac- 

 ticed to advantage on drilled grain, as the 

 harrow will pull out the young grain as 

 well as the weeds in broadcast fields, nor 

 should it be used where the ground is very 

 wet in the spring. It is not particularly 

 effective on fall-sown grain, as the weeds 



