72 CEOP GROWING AND CROP FEEDING 



WHAT IS THE BEST FORM OF POTASH ? 



As we have said, the potash mined in Germany exists in the forms of 

 sulphates, chlorides and carbonates. There is little difference in the rate of 

 availability to the plant of any of these forms, but the effect of the particular 

 form on the different crops is an important matter. It has been. found that 

 while the muriate (or chloride) of potash will produce a heavy crop of tobac- 

 co, it seriously impairs the quality of the leaf, and hence in a tobacco fertilizer 

 it is important to use the sulphate, which is free from chlorides. In some 

 sections it has been found that the Irish potato crop is damaged in quality 

 by the use of muriate, while in other sections the muriate is used exclusively 

 on this crop. The nature of the soil seems to have a great deal to do with the 

 form in which potash is of use to the Irish potato. In the great early-potato 

 growing section of the South Atlantic coast, the muriate has been found to 

 give the finest crop; while in the North and on a he'avier soil, the sulphate is 

 of importance in giving quality to the product. On a clay soil and in a 

 Northern climate we should use the sulphate for potatoes. Crops that have 

 sugar as an important constituent are always more favorably affected by the 

 sulphate than the muriate. Sweet potatoes, sugar beets, strawberries, toma- 

 toes and such should always have their potash in the form of a sulphate free 

 from chlorides. Indian corn and grasses, wheat and oats, are indifferent to 

 the form in which the potash is furnished. 



CRUDE POTASH SALTS. 



As mined in Germany there are two principal forms of the salts in a 

 crude state. These are kainit and sylvanite. There are other forms, but 

 these are about the only ones exported, and by far the larger part of the crude 

 salts that come to this country are in the form of kainit. While the potash 

 in kainit is in the form of a sulphate, it is mixed with such a large percentage 

 of chloride of sodium (common salt) that its action is the same as the 

 chloride, or muriate. Containing so low a percentage of potash, generally 

 a little over 12 per cent., it is a costly form in which to buy potash at any dis- 

 tance from the port of entry, since the freighting of so large a proportion of 

 useless material rapidly runs up the cost of the potash to the farmer, which is 

 the only thing in it which is of any great importance to him. It is also 

 dangerous to use in large quantities in immediate contact with seed, or young 

 plant roots, because of the salt it contains. Some time ago a farmer in the 

 tobacco section of North Carolina wrote to me that he had bad success with 

 the home mixing of fertilizers from a formula we gave him, and that the 



