290 STATE BOARD OF AGRICULTURE. 



USE OF COMMERCIAL FERTILIZERS. 



It is not possible for any man to predict with certainty what the 

 return will be from the use of any particular fertilizer, because so much 

 depends on the season, the physical condition of the soil, etc. It is 

 safe to assume that a soil is lacking in something when it fails to pro- 

 duce a good, average crop, say 40-50 bushels of shelled corn or 25-30 

 bushels of wheat per acre. For all soils under good climatic conditions 

 should be able to produce the above amounts of grain when properly 

 handled. The failure of a soil to yield average crops may be due to 

 several causes, among which may be mentioned the following: im- 

 proper drainage, improper tillage, unfavorable climatic conditions, lack 

 of moisture, lack of humus, acidity, lack of available plant food. 



It will be readily seen from this that only one of these conditions 

 can be remedied by the addition of commercial fertilizers. If the other 

 conditions exist, they should, as far as possible, be corrected before any 

 form of commercial plant food is used. It will be readily seen that all 

 of these conditions except one, are within the power of man to control, 

 at least to a certain degree. 



Drainage. It is not an uncommon sight, especially in the spring, to 

 see large areas in fields where the water is standing anywhere from a 

 few inches to a foot or more in depth. In such cases it is late in the 

 season before the land is in a condition to be worked; consequently if 

 a crop is sown, it is late in getting started and furthermore, such places 

 are liable to be flooded with every heavy rain. In some soils the water 

 may not stand upon the surface, but come to a level within a few inches 

 of the surface. Such soils can be benefitted only by a drainage system 

 that will carry away the excess of water. Commercial fertilizers can- 

 not take the place of drainage. 



Cultivation. The advantages to be derived from cultivation are many. 

 It keeps the ground in good physical condition, makes available some 

 of the insoluble plant food, kills weeds, and when done at the proper 

 time, conserves soil moisture. Commercial fertilizers cannot take the 

 place of cultivation. 



Unfavorable climatic conditions are beyond the control of man. Com- 

 mercial fertilizers cannot overcome unfavorable climatic conditions. 



Moisture. The soil moisture may be controlled to a certain extent 

 by judicious rolling and cultivation. Commercial fertilizers cannot 

 compensate for lack of moisture. 



Humus is decayed and decaying organic matter. It plays an im- 

 portant part in the fertility of a soil. It helps the physical condition, 

 conserves moisture, makes available some of the insoluble plant-food. 

 Humus may be supplied by adding barnyard manure or by turning 

 under green manures, such as clover, cowpeas, rye, etc. Commercial 

 fertilizers do not add humus to the soil. 



Soil Acidity. Soils may become acid as a result of the decomposition 

 of organic matter and possibly from other causes. Some plants are 

 particularly sensitive to an acid condition of the soil, especially alfalfa 



