195 



Potash Plat. 



On this plat, the Nitrogen and Phosphoric Acid are the constants and 

 the form and quantity of potash the variable. Does this soil need po- 

 tash to grow cane ? If so, in what form, and in what quantity shall it 

 be used ? The nitrogen in this plat has been furnished in the form of 

 Sulphate of Ammonia and the Phosphoric acid in Acid Phosphate. The 

 -potash has been supplied in Kainite, Muriate of Potash, Sulphate of Po- 

 tash, Carbonate of Potash, and Nitrate of Potash. Such quantities of 

 each were used as to furnish 25 to 50 pounds of pure potash per acre. 



There were also present the usual Nitrogen and Phosphoric Acid. 

 These experiments have extended over eight years, and are being con- 

 tinued. 



So far, no results of any character, either in the increased sugar con- 

 tent or tonnage per acre have been visible from the use of any form of 

 potash, upon the alluvial lands of the lower Mississippi. Sever d forms 

 of potash, notably the carbonate, and ashes of cotton seed hulls, have 

 rather decreased the yield of cane and injured the physical qualities of 

 the soil, by causing it to run together." That this soil should not re- 

 quire potash in fertilisers adapted to them is to be anticipated from its 

 chemical analysis given elsewhere, which shows an abundance of potash. 

 It is further corroborated by the [magnificent growth of white clover, 

 wild alfalfa, and melilotus officinalis, growing luxuriantly over almost 

 every headland, and by the excellent crops of cabbages, red clover, 

 alfalfa (Medicago sativa), and cow peas, cultivated more or less exten- 

 sively throughout this section. All of these plants are known to require 

 large quantities of potash for their best development Where are they 

 grown better and more successfully than in the alluvial lands of South 

 Louisiana ? 



In New England and the north of Germany, potassic manures are 

 held in high esteem. (^) The application of potash manure has proven 

 .a panacea for clover sickness" on the the soils of Scotland. On soils 

 rich in humus, potassic manures are said to release nitrogen, and thus 

 give excessive growth to plants grown thereon. This is a familiar oc- 

 ■currence to all farmers in the spots where log heaps have been burned. 

 Such spots withstand drought well, since they are better supplied with 

 moisture by capillarity. 



Sources of Potassic Manures. 



Formerly ashes and green sand marl (Glauconite) furnished all the po- 

 tash for commerce and agriculture, but the opening of the Strassfurt and 

 Leopoldshal mines of Saxony have furnished the world with every form 

 of potash. 1 he following are the products : — 



First-Kainite. a crude product of the mines, containing 12 per cent, 

 of potash, and is a mixture of chlorides and sulphates of potash, soda, 

 and magnesia. 



Second- Muriate of Potash, a manufactured article containing 50 per 

 cent, of pure potash. 



(2) The eiporimtnts conducted at the West Indian Experiment Stations lead 

 to the conclusion that, under the conditions of the experiments, the use of potash 

 AS a fertiliser is beneficial to sugar canes in the West Indies. — F. W. 



