116 DRY LAND FARMING 



the seeds of almost any kind of cereal that may be in- 

 troduced, but to a greater exteift they come in flax seed 

 than in the seed of any other kind of grain. This is ow- 

 ing to the greater difficulty in removing foul seeds from 

 flax than from other cereals. That it is so is so far un- 

 fortunate, for in semi-arid areas flax is more commonly 

 sown as the first crop than any other cereal. In this way 

 the land becomes- polluted with weed seeds in many in- 

 stances at the very outset. That it is so is peculiarly 

 unfortunate. The homesteader begins his work on new 

 and clean soil. With the exercise of proper vigilance it 

 could be kept clean at least from many forms of perni- 

 cious weed life for many years to come. 



The weed seeds that are most liable to come in the 

 seeds of grain are wild mustard, wild oats and penny 

 cress, but of course almost any kind of weed may be 

 introduced in this way. Wild mustard and the wild oat 

 are the most baneful among weeds that come to the dry 

 farm. Foul seeds are also frequently introduced with 

 alfalfa seed. Of these dodder is the most dangerous. 



After weeds have been introduced, they are distrib- 

 uted by various methods. These include the following: 

 (1) through the purchase and changing of seed; (2) 

 through the medium of threshing machines ; (3) in the 

 droppings of cattle, and (4) by the agency of birds. But 

 the most potent agency by far in the distribution of 

 weeds after they have been introduced, especially in the 

 Plains region, is wind. The extent to which this agency 

 may scatter the seeds of some kinds of weeds is in a 

 sense without limit. The seeds of the Russian thistle, 

 tumbling mustard and other weeds of the tumbling or- 

 der, may be thus carried to distances that are in a sense 

 incredible, nor is there any way of guarding against such 

 introduction. Certain styles of wire fencing are in some 

 sense a safeguard but not in all instances, as the weeds 

 may pile up to such an extent that they form an inclined 



