120 STATE BOARD OF AGRICULTURE 



"field peas with oats, hogged-down" in mid-summer and plowed under, is a good 

 preparation for a wlieat crop, and the pigs by increased formation of muscle will 

 get a good start towards bacon. 



Pbofiphoric ^Ic/c?.— Mineral phosphates are found in all fertile soils, usually in very 

 small amount and always in the insoluble form, the phosphoric acid being combined 

 with lime, magnesia, alumina or oxide of iron. All these phosphates are insoluble 

 in water. The most ready and valuable source of supply is bones; but the buffalo 

 bones of the western plains have been gathered, and the slaughter houses furnish 

 most of the bones now. Sometimes a quantity is found on the farm, and the ques- 

 tion arises how to make the best use of them. By composting the broken bones 

 with twice as much moist wood ashes, the bones in a few months break down and 

 become so brittle that they will break under a blow of the shovel, and may then 

 be mixed with the ashes to make a valuable manure. Broken bones composted 

 with stable manure will decompose, but more slowly. 



Phosphate rock is found in large deposits in South Carolina, Florida, Tennessee 

 and Canada, in the form of phosphate of lime. For the most part it is found in 

 hard, stony masses, entirely insoluble in water, and very slowly decomposed by 

 weak acids and by the roots of living plants in the soil. Sulphuric acid decomposes 

 it, removing a part of the lime, and forming a soluble or "superphosphate." This 

 soluble phosphoric acid, and a modified form known as "reverted," are readily 

 taken up by the plant and contribute to its growth. The soluble and the reverted 

 are placed together and constitute the available phosphoric acid. 



Wood ashes, whether fresh or leached, contain a sensible quantity of phosphate of 

 lime, which adds to the manurial value of this neglected material. 



Potash. — The commercial supply of potash is found in the form of muriate and 

 of sulphate of potash. These are derived from the Stassfurt mines of Germany. 

 For many crops, the potash is equally beneficial whether in the form of muriate 

 or sulphate, but certain crops, such as the potato and sugar beet, are injured by 

 the presence of muriates (or chlorides), while they are benefited by potash as 

 sulphate. 



A limited domestic supply of potash is found in wood ashes in the form of 

 carbonate, which is more beneficial than muriate or sulphate because of its alkaline 

 quality. 



The farmer should remember that his most valuable mine of potash is the clay 

 and loam of his farm. Every fertile soil contains potash, but the clay is especially 

 rich in potash, and by the slow chemical changes in such soil, promoted by tillage, 

 potash is constantly set free for the use of plants. 



CROPS SPECIALLY BENEFITED. 



The question, w'hat crops will be specially benefited by a given fertilizing ele- 

 ment is often asked. A full answer is not easily found, but a few suggestions 

 are offered. 



Nitrogenous Manures. — The leguminous crops, such as the clovers, peas, beans, 

 vetches, etc., are called nitrogen-producers, because they derive most of their 

 nitrogen from the air, and they receive little benefit from the use of nitrogenous 

 manures. Sugar beets produce a much larger crop when fed with manures rich in 

 nitrogen, but the quality of the beet is greatly reduced, tlie overgrown beets 

 containing an increased amount of non-saccharine matter, lowering the co-eflicient 

 of purity. Such manures and unfermented stable manure are avoided in raising 

 sugar beets. 



Combined nitrogen is often called a stimulant, because it promotes a rapid and 

 large growth of leaf and fibre. In truck farming and raising of succulent crops 

 for immediate sale in the market, the forcing quality of nitrogen comes in good 

 play. This is seen in the growth of juicy fruits like the strawberry. Some 

 gardeners, as soon as the frost is out of the ground and winter mulch is removed, 

 apply 300 to 400 pounds per acre of dried blood or hen manure, raking it into the 

 ground, and securing a larger crop thereby. 



The purest example of a nitrogenous manure is nitrate of soda. It is entirely 

 soluble in water, and hence liable to be washed out of the soil in a wet spell unless 

 a growing crop appropriates it and saves from loss. In a very dry season it some- 

 times "burns the crop." Its best effect is seen when it is applied to a crop which 

 has little power to obtain a supply of nitrogen, yet needs to make a i"apid growth in 

 a short time to produce a paying crop. A good illustration is winter wheat, which 

 makes such a wonderful growth in the latter part of May and in June in 



