142 COTTON 
4. Acid phosphate is usually our most economical 
carrier of phosphorus. 
5. Muriate of potash is an economical carrier of 
potassium. 
6. Kainit, which contains only one-fourth of the 
quantity of potassium found in muriate, is usually 
preferred in cotton manures because it is believed 
to be beneficial in warding off rust. 
7. Nitrogen is especially concerned with the 
growth of leaves and stems. If your cotton leaves 
and stems have been small, therefore, and the 
nitrogen supply in the soil has not been increased 
by the growth of some leguminous crop, it would 
be well to increase the nitrogen content of the 
formula you select. On the other hand with 
marked growth of leaf and stem, the quantity of 
nitrogen in any formula may be decreased or alto- 
gether abandoned. 
8. When cotton follows clover, cowpeas, or other 
legumes, little or no nitrogen will be required in 
the fertilizer. 
9. When stem and leaf growth are abundant, but 
yield of seed and lint below what it should be, 
phosphorus and potassium—especially the former 
—are needed. 
10. In a general way, on average cotton soils 
the best results are obtained when nitrogen, phos- 
phorus, and potassium are combined in the propor- 
tion of about three or three and one half parts 
phosphorus, one part nitrogen and one part 
potassium—unless the nitrogen be already sup- 
plied by leguminous crops. 
THE FORMULA TO USE 
It is impossible to suggest a formula, or even 
