10 CIKCULAR NO. 121, BUEEAU OF PLANT INDUSTRY. 



LATE THINNING AND CLOSE PLANTING. 



Plants are usually thinned to stand 18 inches or more apart in the 

 row when they are about 5 inches tall. Late thinning, when the 

 plants are about 10 inches tall, to leave them 8 to 12 inches apart 

 will in all probability provide better conditions for cultivation and 

 harvest, as well as a larger crop.* Durango cotton adapts itself 

 especially to this plan. From the results of tests of the new method 

 of thinning it would appear that marked progress can be expected 

 in cotton culture by the introduction in the Imperial Valley of late 

 thinning to close distances. It is suggested that cotton growers in 

 the valley try this new method on a few acres of their plantings. 



CULTIVATION. 

 HARROWING YOLTNG COTTON. 



Crusted soil, occasioned by rains or by irrigation water covering 

 the rows while the plants are small, should be thoroughly stirred by 

 harrowing across the rows. This treatment is of great benefit to 

 young plants and \vill usually save the stand if the seed is in process 

 of germination. 



INTERTILLAGE. 



Thorough cultivation of a nature to maintain a thick mulch on the 

 surface should be practiced following irrigation as long as the plants 

 will permit passage between the rows. This will insure a steadier 

 and more even supply of water to the plants and thus a more normal 

 growth. 



IRRIGATION. 



IRRIGATION BY FLOODING. 



Flat irrigation, which allows the water to stand against the plants, 

 is not necessarily harmful on soft lands, where no caking of the soil 

 can occur about the plants, unless the water is left long enough to 

 scald. Flat irrigation on hard land has the disadvantage of causing 

 a caking of the soil, which is especially undesirable about young 

 plants. 



INFREQUENT EARLY IRRIGATION. 



Irrigation should be deferred as long as possible after the cotton is 

 up to stand. It is undesu'able to crowd the young plants by early 

 irrigation into excessive vegetative growth, which will later have to 

 be sustained by heavy and frequent irrigations and will result in a 

 crop difficult to pick because of oversized plants. Other disad- 

 vantages result unless precaution is taken to control the growth of 

 plants when young. 



' See U. S. Department of Agriculture, Bureau of Plant Industry, Circular Ho, article entitled "A new 

 system of cotton culture," by O. F. Cook. 



[Clr. 121] 



