The Birmingham age-herald., 1917-10-04


 mist have found out to a certainty how much plant food is used in growing the root, stalk, leaf and seed, and how and when commercial plant food can be fed to the best advantage. This exact knowl- edge affords an important part of the foundation of the modern science Of plant feeding, or the science of fertiliz- ing on which the two great industries farming and the manufacture of fertil- izers--are based.
 Can nitrogen be grown?
 Some nitrogen can be grown or, more critically speaking. can be taken from the air, without robbing the soil. This is done by growing legumes. A legume is the family name for such plants as The clovers, alfalfa, cowpeas, peanuts, soy beans, velvet beans. lespedeza or Japan clover, beggar weed, vetch and certain other plants.
 How do legumes get nitrogen from the air?
 Legumes do not drink in nitrogen from the air. In fact, legumes do not take ni- troSen directly from the air at all. All that the legume has to do with it is to accommodate a certain kind of bacteria with site for a nitrogen plant. These nitrogen fixing bacteria set up business exclusively on roots of the legumes among farm crops.
 
 they usually develop swellings or nodu.es on the roots Here in these nodules, pi- trogen is taken from the air contained in the soil and converted into nitrogen ous plant food If the soil becomes water logged, the bacteria smother. If water becomes scarce, these root laboratories shut down., for bacteria need some they do not do well unless lime is ap- piled.
 Why are soils inoculated?
 Sometimes a soil does not naturally have supply of these bacteria which cause the root nodules to develop In that case they can be bought from people who make a business of growing them They are in a form that can be easily and successfully applied direct to the seed which is the better way It is also pos sible to transfer these bacteria from 2 field where they are known to be doing thriving business to another field that is in need of them by taking up some o1 the dirt from the first field and carrying it to the second and narrowing it in One must be careful, however, not to lei the soil stay very long in the sunshine for the sunlight soon weakens or kills tho bacteria which it is desired to increase The second method cannot be as com plete as the first, and, therefore, it i. not as satisfactory.
 can all the nitrogen that IS neeQeQ DC grown or fixed by plants?
 It must be remembered that while leg umes gather nitrogen, they also take il from the soil in combined form. As 6 rule, they draw heavily upon the com. bined nitrogen supplies already in thu soil, and furthermore it costs money tt grow these crops merely for turning un- der. It is more profitable to harvest them and buy whatever nitrogen is need o1 Tn Ia tot erable portion of the nitrogen must nee essarily be purchased and added to tn, soil if the proper amount for abundant plant growth is to be supplied. Ever legumes need commercial nitrogen of 7 quickly available form on poorer soils especially in the early stage of theil growth
 From what sources are commercial nj trogen food obtained?
 The main sources of commercial nitro gen are: Nitrate of soda from Chile sul phate of ammonia, chiefly by-product O. modern coke ovens; cotton seed mea and other oil meals; tankage and blood by-products of packing houses; bones ant fish scrap; guano, partly decomposed O. preserved bird droppings from Peru ant many other parts of the world: and at mospheric nitrogen, fixed as cyanami( and nitrates.
 How is nitrogen used in the develop
 
 ment of a plant?
 The chief use of nitrogen in the de velopment of plant is in the produc tion of stalk and leaves. A dark green sturdy appearance of a plant indicates that sufficient nitrogen is being obtained Frail, yellow looking plants usually giv, evidence of a shortage of nitrogenou food. In some plants like cotton, pea nuts, sy beans, velvet beans and peas an unusual amount of nitrogen also zoe. into the seed. It Is this nitrogen il these plants and. plant products whicl makes them so valuable as sources O protein for feeding farm animals.
 Is nitrogen subject to teaching?
 Nitrogen teaches very readily, mucl more so than phosphoric acid or potash. How much nitrogen do nodules O. legunes gather, and how much nitrogen is removed when legumes are removed for hayf
 The soil neither gains nor loses in nj