Johnson Grass Co.xtkul, 353 



easier the next year when cotton is planted. If cotton is used first the 

 Johnson grass must be fought the hardest at a time when the young 

 cotton plants must be handled with greatest care; and while the old 

 rootstocks of Johnson grass can be brought under control, the growing 

 cotton interferes with late cultivations that should destroy seedling 

 plants from seed brought in by late summer irrigations. Many of these 

 seedling plants by fall forn; quite large and vigorous rootstocks. This 

 necessitates a great deal of work the following spring before the plant- 

 ing of the next year's crop of corn, if a green manuring crop is 

 planted on this land prior to putting it in corn a very troublesome 

 growth of Johnson grass will appear before the crop is large enough 

 to be of material advantage to the ground. Thus in Field E, in 1917, 

 a crop of tepary beans had to be turned under before their value as a 

 green manure had paid for the expense of planting them. The financial 

 returns from Field F have been materially increased over those from 

 Field E by virtue of the fact that the prices of cotton in 1917 were 

 almost double the prices for 1916, which also were abnormally high; 

 while the prices of corn did not change correspondingly. On account 

 of conditions not regulated by the experiment we secured in 1917 

 double the yield of cotton obtained in 1916. 



Field G : When land is held fallow in summer and seeded to small 

 grains in winter, ample time is available to put the seed bed in perfect 

 shape, and on such land a very high yield of grain may be obtained. 

 Yields of 45 to 50 bushels of wheat per acre, and the abnormally high 

 prices of grains in 1917, left considerable profit from the treatment of 

 Field G. Shortage of labor at critical times and the thorough wetting 

 of the land by a 3-inch rain in early September, 1916, materially reduced 

 the efficiency of our Johnson grass control work on this field. Lack of 

 plowing faciHties immediately after the removal of the 1917 grain crop, 

 allowed further opportunity for the recuperation of Johnson grass. As 

 a result, the land is still quite badly infested though not so seriously 

 as to make it particularly difficult to control. If it had been possible 

 for us to conduct all our cultural operations on this field as soon as the 

 need was manifest, there is no question that the Johnson grass would 

 have been almost completely destroyed. 



Field H: Continuous dry fallow is very efifective and does not 

 demand a very great expenditure of labor ; but the danger that a heavy 

 rain will undo a good deal that has already been accomplished and the 

 loss of the use of the land makes this method impracticable. While 

 continuous fallow does not demand a great deal of labor it sometimes 

 requires considerable work in a very short time, usually at a season 

 when other parts of the farm require attention. 



