FERTILIZERS. 73 



applied as long as possible before the crop is sown. It is well to mix with earth, or to com 

 post, before applying, especially if used shortly before sowing the seed. And, in general, 

 potash salts are well adapted for composting with muck, earth, stable-manure, phosphates, 

 fish, and the like. 



6. The best results are generally obtained by using potash salts not alone, but with 

 other fertilizers, as superphosphates, guanos, and fish. Mixtures of these latter with potash 

 salt form &quot;complete fertilizers.&quot; The proper use of potash salts is as adjuncts to other fer 

 tilizers. 



7. From 200 Ibs. to 400 or 500 Ibs. per acre of the higher, and 300 to 600 Ibs. of 

 the lower grades, are appropriate quantities. 



8. The question of the need of potash in a given soil can be best decided by actual 

 trial. It will be generally advisable to test the question by experiments on a small scale 

 before making large purchases.&quot; 



Magnesia is contained in many soils, and in limestones, which are often called mag- 

 nesian limestones, when this element is found in them in large quantities. 



It is also found in wood-ashes, oyster-shell lime, New Jersey green marl, and various 

 other fertilizing materials. 



The waters of the ocean contain magnesia, to the presence of which is attributed the 

 peculiar bitterish taste it possesses. It is estimated that every cubic foot of sea-water con 

 tains two and a half ounces of magnesia. It is supposed that the celebrated Strassfurt 

 deposit referred to in previous pages, which is one of the principal sources of commercial 

 magnesia and its salts, is the residue of some ancient sea. 



The trap rocks of the Hudson River Palisades have been found on analysis to sometimes 

 contain ten per cent, of this substance. The ashes of grains of some wheat have been found 

 to contain 11.75 per cent, of magnesia; hence, a soil deficient in this element would not pro 

 duce wheat, however rich it might otherwise be. Since lime is abundant in wheat straw, a 

 good calcareous soil, when lacking magnesia, might produce straw without any wheat, or, if 

 the heads were formed, they would be very imperfect in wheat formation. 



Leaves of Trees can be made available in furnishing fertilizing substances in the 

 form of potash, phosphoric acid, and lime, in limited quantities. Used in the compost heap, 

 as bedding for stock, or as a covering for plants to protect them in winter, they are valua 

 ble. When mixed with the compost heap, or with the manure from the stables, they will 

 soon become decomposed and add to the fertilizing properties of the mass, and will well repay 

 the farmer for gathering, providing he is not required to go a long distance to obtain them. 

 The best time for gathering them is when damp with dew or rain, as they can then be put in 

 a more compact form, and be more easily handled. If there are boys upon the farm, a late 

 autumn day could not be spent by them in labor much more profitably or pleasantly than in 

 gathering and storing leaves for the various uses to which they can be applied. Stored under 

 shelter, in some barn or shed, they should be spread and raked over occasionally in order to 

 dry them, if designed for the bedding of stock. Besides being valuable, the gathering of 

 leaves that would otherwise be blown about the farm buildings, giving the premises an 

 untidy appearance, would be of advantage to any farm. 



Tobacco StemSi The refuse of the cigar manufactories, consisting of the stems and 

 midribs of tobacco leaves, have been utilized to a considerable extent as fertilizers, especially 

 in the culture of tobacco. 



Analysis proves that they are a good general fertilizer, supplying all the elements of 

 plant-food to a certain extent, and are especially rich in potash and lime. They are liable to 

 be rather variable in composition, especially in respect to moisture. They are generally 

 plowed into the soil a few weeks before planting. On clayey soils, they are frequently ap 

 plied in autumn, but this practice would not be advisable on a sandy or porous soil, as the 



