PERENNIAL SOW THISTLE 



in commercial seed but has been found in blue-grass seed and in lawn- 

 grass mixtures. 



Eradication. — When the first stray plants appear they should be 

 pulled or spudded out, before they mature seeds. Constant watch- 

 fulness is necessary to detect them. When a field has become so 

 badly infested that the thistles interfere with crop growth, early sum- 

 mer fallowing is advisable. Short rotations should be followed in 

 sections where the weed is very common. A three-year rotation of 

 (1) grain, (2) clover, and (3) a cultivated crop; thorough prepara- 

 tion of the land ; and clean cultivation will keep the weed in check. 



The specific treatment that follows will give good results where 

 the weed has become well established. Immediately after the re- 

 moval of the grain crop, plow the land deeply, preferably early in 

 August. After plowing, disk frequently enough to keep the leaves 

 from starting. The disking should be kept up until frost stops the 

 growth of the plants. . Start disking early in the spring or replow 

 fairly early. Cultivate the land frequently until about June 1 and 

 plant thickly to fodder or ensilage corn in rows from three to three 

 and one-half feet apart. Cultivate the corn frequently until it shades 

 the ground completely. Hand hoe if necessary. Remove the corn 

 by September 15, plow the land, and sow immediately fall rye. In 

 the spring sow clover in the rye and harrow. The following year 

 cut the first crop of hay and plow under the second. Plant corn the 

 next year and work into a short rotation. Where cultivated crops 

 can not be grown successfully or can not be used, buckwheat, fol- 

 lowing early summer fallow, may be grown quite satisfactorily for 

 smothering out the thistles. Vigilance, prompt and thorough culti- 

 vation, and short rotations are necessary in the eradication of sow 

 thistles. 



