574 IOWA DEPARTMENT OF AGRICULTURE 



farmer should use hog pasturing as a means of exterminating the hind- 

 weed. If it fits into his scheme of farming and the difficulties are not too 

 great, it would be well to employ it. Each case is a problem in itself. 

 Where the conditions are favorable hogs are likely to prove most effective 

 means of getting rid of this weed. 



OTHER METHODS OF ERADICATION. 



Pasturing with s/ieep.— Pasturing with sheep has been reported to have 

 killed the bindweed, but the evidence on this point is meager. It is pos- 

 sible that if a grass pasture is run with a sufficient number of sheep for a 

 long enough time the weed will disappear. Grass can stand close pastur- 

 ing better than most weeds, ,if they are grazed equally close, but it re- 

 mains to be demonstrated whether or not this plan will completely eradi- 

 cate the bindweed, and, if so, how many years it will require. In parts 

 of the far West, where grass becomes brown and dry during the summer 

 season, sheep are reported to have killed the weed, for the reason that it 

 is often the only vegetation that remains green in the pasture at that sea- 

 son. There is no doubt, however, that sheep are of assistance to hogs in 

 pasturing for the eradication of bindweed. They eat the tops close to 

 the ground, which checks the growth of the weed. 



Use of smothering crops. — By smothering crops are meant those crops, 

 other than alfalfa, that exert a shading effect on weed growth, such as 

 cowpeas, soy beans, millet, sorghum, and buckwheat. No extensive trials 

 of these crops as a means of controlling the iDindweed have been made, so 

 it is impossible to define at the present time their adaptability for this 

 purpose. With a continuous succession of such crops, and when thick 

 stands are secured, it is probable that in time the weeds would be much 

 reduced. At best, however, these crops are hardly as effective as alfalfa. 



Use 'Of artificial smothering material. — Building paper, manure, beet 

 pulp, apple pomace, straw, and other litter have been much used in the at- 

 tempt to smother out bindweed growing in patches. It is necessary to 

 apply such material, except building paper, quite thickly on the ground 

 to prevent the weed from pushing through, as it has been known to go 

 through a thickness of 2 feet. This method is therefore rather expensive 

 and is not applicable to any but small areas. Indeed, in most cases it is 

 misdirected energy, which could be employed more profitably in some other 

 direction. The use of building paper has been tried with some success on 

 small areas where the laps were carefully weighed down with soil to ex- 

 clude all light. Such paper can be purchased at from $2.25 to $4 per 

 1,000 square feet, depending on the thickness of the ply, which is at the 

 rate of $97 to $172 per acre. This cost makes the method impracticable 

 except for very small areas. The thin ply would be about as satisfactory 

 as the thick. If the bindweed were inclined to grow through at the laps 

 it would be necessary to lay another thickness of the paper, the laps run- 

 ning at an angle to those underneath. The paper would probably have to 

 be renewed each season, and it would take as long to subdue the weed as 

 it would by means of clean cultivation. 



