FIELD, ORCHARD, AND GARDEN CROPS 



155 



preserve a soil-mulch, but not to break the surface roots. It should 

 not continue too late, else it will produce growth at expense of 

 fruit. 



The great labor of cotton production is picking the crop, a 

 tedious and costly operation which has to be performed by hand. 

 Then the fiber is ginned to remove the seed, and the lint is pressed 

 by machinery into large bundles, called ' bales,' each weighing 

 about five hundred pounds. The baled cotton is sent to mills, 

 where it is spun into thread and woven into cloth. 



Cotton makes only moderate demands on the soil, but it is often 

 profitable to use fertilizers to hasten its maturity. When plant 

 food is scarce or unavailable, 

 cotton needs to have supplied 

 phosphoric acid, nitrogen, and 

 potash. The cheapest way to 

 furnish the nitrogen is usually 

 to precede cotton with a nitro- 

 gen-gathering crop, such as 

 cowpeas or crimson clover. 

 If this is done, it will be 

 necessary to furnish only the 

 cheap mineral elements, phosphoric acid and potash. 



Cotton lint is composed almost entirely of carbon, obtained from 

 the air. If only this be removed, cotton takes less fertility from 

 the land than almost any other crop. The seeds remove twenty- 

 one times as much mineral matter as does the lint. They should 

 be replaced by their equivalent in fertilizing elements. 'Re- 

 placed,' we say, for good farmers now seldom use cotton seed 

 for a fertilizer, as they did some years ago, while poor ones left 

 them to accumulate around the gin, like sawdust around a mill. 



Now the seeds tire usually sold to oil mills, which extract the oil. 



FIBER 



This diagram shows the amount of potash f 

 phosphoric acid, and nitrogen removed from 

 an acre of soil by a crop of cotton, producing 

 a bale of cotton and 1000 Ib. of seed. 



