254 



ARID AGRICULTURE. 



COCKLE All farmers are acquainted with the pink 



blossoms of cockle in their grain fields and with 

 the round, black seeds in their threshed grain. 

 The amount of damage done by cockle is very 

 great. We have heard a good word for cockle 

 from one man, who fattened his stock on the 

 ground seed. Nothing has been published re- 

 garding the feeding value of cockle seed, but it 

 may be worth investigating. Cockle is easily 

 killed by clean culture. The great difficulty is 

 that unclean seed is so often planted. It should 

 be watched and killed down in waste places and 

 on the borders of fields. 



PRICKLY 

 LETTUCE 



FOX TAIL 

 OB WILD 

 BARLEY 



The wild or prickly lettuce is one of the most 

 common and one of the worst introduced annual 

 weeds. It is closely related to the cultivated let- 

 tuce, but has prickles on the smaller leaves. 

 These plants have the habit of twisting their 

 leaves so that the edges point north and south. 

 It is one of the most unsightly winter weeds in 

 fence corners and along road sides. It produces 

 a large amount of seed that is distributed by the 

 wind and irrigation water. Clean culture is the 

 remedy. It does no good to mow this weed as it 

 branches freely from any part of the stem left 

 above ground when it is cut off and will ripen 

 seeds in a remarkably short time. 



The squirrel tail grass, commonly called Fox 

 Tail in the West, is one of our very worst weeds. 



