The cheapest way of cultivating a crop is to prevent grass and weeds from rooting, not to wait to destroy them after they are well rooted. To do this, it is well to run the two-horse smoothing-harrow over the land, across the rows, a few days after the young plants are up. Repeat the harrowing in six or eight days. In addition to destroying the young grass and weeds, this harrowing also removes many of the young cotton plants and thereby saves much hoeing at "chopping-out" time. When the plants are about two inches high they are "chopped out" to secure an evenly distributed stand. It has been the custom to leave two stalks to a hill, but many growers are now leaving only one. The number of times the crop has to be worked depends on the soil and the season. If the soil is dry and porous, cultivate as often as possible, especially after each rain. Never allow a crust to form after a rain; the roots of plants must have air. Cultivation after each rain forms a dry mulch on the top of the soil and thus prevents rapid evaporation of moisture. If the fiber (the lint) only is removed from the land on which cotton is grown, cotton is the least exhaustive of the great crops grown in the United States. According to some recent experiments an average crop of cotton removes in the lint only 2.75 pounds of nitrogen, phosphoric acid, potash, lime, and magnesia per acre, while a crop of ten bushels of wheat per acre removes 32.36 pounds of the same elements of plant food. Inasmuch as this crop takes so little plant food from the soil, the cotton-farmer has no excuse for allowing his land to decrease in productiveness. Two things will keep his land in bounteous harvest condition: first, let him return the seeds in some form to the land, or, what is better, feed the ground seeds to cattle, make a profit from the cattle, and return manure to the land in place of the seeds; second, at the last working, let him sow some crop like crimson clover or rye in the cotton rows to protect the soil during the winter and to leave humus in the ground for the spring. The stable manure, if that is used, should be broadcasted over the fields at the rate of six to ten tons an acre. If commercial fertilizers are used, it may be best to make two applications. To give the young plants a good start, apply a portion of the fertilizer in the drill just before planting. Then when the first blooms appear, put the remainder of the fertilizer in drills near the plants but not too close. Many good cotton-growers, however, apply all the fertilizer at one time. [Illustration: FIG. 187. WEIGHING A DAY'S PICKING OF COTTON]