Because of the wide variation in the amount of available plant food 

 in soils, the differences in the needs of plants, and the necessity of the 

 farmer gaining some definite information regarding the nature of the 

 fertilizers he is using and 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 indi- 

 cate 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 suf- 

 ficiently developed to gather their own supplies. The future health and 

 vigor of the plant will depend on : (i) 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, and various soluble salts found in the soil, and from these builds 

 up the complex sugars, starches, fat, and albuminoids which are essen- 

 tial for the life processes of the plant and which are the only foods of the 

 animal. It is subject to improvement 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 draw- 

 ing 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 

 understanding 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 



