125 



Pruning. — Even the annual plants may require some pruning if they 

 show any tendency to produce wood and leaves at the expense of flowers 

 and seeds. In such a case the tops should be nipped off when podding 

 commences. If the plant is grown as a perennial, pruning is necessary, 

 and this is done during the next month after the crop is gathered in 

 April. It is usually considered advisable to prune down to about 4 feet, 

 but much depends upon the soil. 



The crop of the perennial cotton begins to come in towards the end of 

 September, and lasts till the end of December. A second crop lasts 

 fiom the end of February until the middle of April. 



Manures. — As the cotton-plant is cultivated for the sake of the fibre 

 which envelopes the seeds, attention is directed to the chemical analysis 

 of the seed which bears the fibre as well as to the fibre itself, in order 

 to discover what substances these extract from the soil that have to be 

 replaced. 



An analysis of the ash of cotton fibre shows that these ingredients, 

 are : — 



Percentage. 

 Potash 31-05 

 Lime 17-09 

 Phosphoric acid 12*32 

 in other words 10,000 lbs of cotton fibre abstract from the soil 

 lbs. 



Potash 31 

 Lime 17 

 Phosphoric acid 12 



An analysis of the ash of cotton-seed gives 

 Percentage 

 Potash 19-40 

 Lime 29*79 

 Phosphoric acid 45 . 35 



The seed is thus much more exhausting on the soil tl an the fibre or 

 "lint," and when its greater proportion is considered, it is probable that 

 while for every bale of cotton, the lint takes 4 lbs of soil-ingi\ clients, the 

 seed takes 38 lbs. 



If, therefore, the seed after expression of the oil, is utilised as cattle- 

 food, and returned to the ground in the form of manure, the crop will 

 be one of the least exhausting known. On the contrary, if the seed is 

 permanently removed, heavy manuring will be necessary to preserve 

 the fertility of the soil. 



The best manures are superphosphate of lime (containing phosphoric 

 acid and lime) and potash (either wood ashes or potash salts). Salt 

 appears to be peculiarly beneficial, and good cotton lands are often low- 

 lying, subject to the influx of tides, but in such a situation high ridg- 

 ing is necessary. 



All refuse from the plant should be returned to the soil, either by 

 being burnt and the ashes ploughed in, or by turning cattle in to feed 

 it down. 1 -urning ensures destruction of eggs of hurtful insects or spores 

 of destructive fungi. 



Guano and other nitrogenous manures should be avoided, as causing 

 the plant to run too much to stem and leaf. 



