MORE ABOUT WEEDS 



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color from dark green to crimson, especially on the most 

 exposed parts. When the ground becomes frozen and the 

 November winds blow across the prairie, the small root is 

 broken or loosened and pulled out. The dense, yet light, 

 growth, and the circu- 

 lar or hemispherical 

 form of the plant, fit it 

 most perfectly to be 

 carried by the wind. It 

 goes rolling across the 

 country at racing speed, 

 scattering seeds at ev- 

 ery bound. 



The best method of 

 destroying Russian 

 thistles is by plowing in 

 August or September, 

 before they have grown 

 large and stiff, and be- 

 fore they have gone to 

 seed, using care that all 

 seeds are well turned 

 under. If the season 

 be long and weeds come 

 through the furrow, it 

 may be necessary to 

 harrow the land before 

 winter. Burn over the 

 stubble fields as soon as possible after harvest. Cut the 

 stubble with the mowing machine if the fire does not 

 burn everything clean. Cutting the stubble and thistles 



FIG. 78. Branch from Russian thistle, 

 showing appearance of plant when seeds 

 are mature; a, from a young plant, show- 

 ing the appearance before the dry season; 

 b, mature seed. 



