the effect of these upon crops grown, we strongly recommend those who contemplate 

 using fertilizers to commence in a small way and prove for themselves whether 

 they can or cannot use these substances with profit. The object of this bulletin 

 is to point out some of the main features regarding plants, soils, and fertilizers, 

 which should be known in order that the work may be done intelligently, and to 

 indicate briefly how experimental plots may be arranged to show whether special 

 fertilizing materials are or are not required. 



THE PLANT. 



Most young plants start from a seed, which contains an embryo, or germ, 

 that is extremely rich in albuminoids, fat, phosphates, and potash. The seed 

 also contains a store of food, in the form of starch, fat, etc., intended to nourish 

 the young plant until the roots and leaves are sufficiently developed to gather 

 their own supplies. The future health and vigor of the plant will depend on: 



(1) the amount of food available to the tiny rootlets sent out by the young plant; 



(2) the temperature of the soil, (3) an abundance of sunshine, and (4) a sufficient 

 supply of oxygen. The plant requires oxygen for respiration, and it gives off 

 carbon dioxide as a result of the oxidation of its food, that is, it breathes; it 

 gives off water from its leaves, or lungs, it assimilates food, and it even excretes 

 waste material. In all this it is very similar to the animal. But it even goes 

 further, and collects its food from the simple substances, such as carbon dioxide, 

 anc various soluble salts found in the soil, and from these builds up the complex 

 sugars, starches, fat, and albuminoids which are essential for the life processes 

 of the plant and which are the only foods of the animal. It is subject to im- 

 provement by selection and breeding, as is the animal, but, unlike the animal, 

 it is entirely dependent upon the supply of food constituents within its reach, 

 and it has no way of drawing attention to its wants, excepting as its appearance 

 may make them known to the careful and trained observer. A clear conception 

 of the fact that an infant plant, like the infant animal, requires warmth, air, 

 sunshine, and an abundance of easily absorbed food, will greatly aid in under- 

 standing the conditions under which it will make the best growth. 



Food of Plants. 



The plant's food is derived from the atmosphere and from the soil. From 

 the atmosphere it gathers carbon dioxide and oxygen, and some plants, through 

 outside agencies, are able to collect nitrogen. Nearly fifty per cent, of the dry 

 matter of a plant is made up of carbon which is entirely derived from the carbon 

 dioxide of the air. Although this compound forms but 3 or 4 parts in 10,000 

 parts of the atmosphere, the quantity is, sufficient, owing to the wind continually 

 bringing fresh supplies to the leaves. Thus there is" an abundance of air around 

 the leaves of the plant, but, if the soil is not open and porous, there may not 

 be enough in contact with the roots, for it is worthy of note that air in the soil 

 in which crops are growing is as essential to the life of plants as air in the stable 

 is to the animal. This ventilation of the soil is necessary to supply oxygen 

 required in germination of seed, to permit the roots to live, for they, too, must 

 breathe, and to supply this life-giving element to the millions of little organisms 



