WEEDS 



169 



Fighting the 

 Weeds. If a weed 

 is an annual, then 

 the problem is to 

 prevent the seed 

 from ripening or 

 spreading. The 

 seeds of some of 

 these weeds will 

 grow after several 

 years, so if the 

 farmer allows them 

 to become abun- 

 dant in his fields 

 some of the seeds 

 will grow each 

 year and each year 

 he must fight them. 

 It is a good plan to 

 harrow well just 

 before planting a 

 crop. This kills 



the sprouting weeds and gives com or other crops 

 a chance to get ahead. Weeds are easiest to kill 

 when they are just starting to grow. 



When weeds get a start in a pasture field a flock 

 of sheep will soon kill them by eating off the leaves. 

 Sheep will eat most all kinds of weeds. When 

 weeds get a start in an alfalfa field they may be 

 checked by the use of the spring-tooth harrow or 



Fig. 91. Canada thistle. 



