FERTILITY AND FERTILIZERS 



The following four articles on manures and fertilizers have been com- 

 piled from the evidence of Dr. F. T. Shutt, given before the Standing 

 Committee on Agriculture. 



Crop production may be increased either by extending the acreage or by increasing 

 the yield per acre. The resulting output may be the same in either case, but the profit 

 to the farmer will not be the same. The farmer's profit will generally be found in 

 increasing the yield. This, in many cases, is at present below what is profitable. 

 What are the means by which it may be raised? 



One of the most important factors governing yield is soil fertility. It is not by any 

 means the only factor. Besides the amount of available plant food contained in the 

 soil, moisture, temperature, vigour of seed, and a number of other conditions have a 

 bearing on the success or failure of a crop. Nevertheless it is one of the prime factors in 

 determining yield. 



If available plant food is deficient, the crop will be deficient both in quality and 

 quantity. It is therefore fundamental to successful farming that fertility be maintained 

 where it is abundant and increased where it is deficient. 



THE IMPORTANCE OF HUMUS 



Semi-decomposed vegetable matter, or humus, is probably the most valuable of all 

 soil constituents. This is the element that gives to virgin soils their extraordinary rich- 

 ness, and it is the exhaustion of this element by poor farming that destroys fertility. 



What are the functions that render humus so important? First, humus is nature's 

 guardian for the important element nitrogen. When the humus is burned out of the 

 soil by irrational methods of farming, the nitrogen goes with it, and the cost of commercial 

 nitrogen is three times that of phosphoric acid and potash, weight for weight. 



The productiveness of a soil is governed largely by its physical and mechanical 

 condition. These things depend to a great extent on the amount of humus it contains. 

 The soil must not only contain food available for the growing plant, but it must offer a 

 comfortable medium for the germination of seed and for the growth and extension of the 

 young and tender rootlets. Soil to be comfortable to the plant, must be in the right 

 condition of tilth, must give access to air and retain moisture. Humus assists in all these 

 functions. 



The bacteria of the soil feed upon humus. Provided the soil is warm, moist, and 

 well aerated, the more humus it contains, the better will they thrive. The function of 

 soil bacteria is to convert soil elements into forms suitable for the use of plants. No 

 humus, no bacteria; no bacteria no plant food; hence no crop. 



THE VALUE OF MANURE 



Farmyard manure is the most effective general fertilizer that we can apply. A 

 ton of fresh barnyard manure of good quality contains, on an average, 10 pounds of 

 nitrogen, 5 pounds of phosphoric acid and 10 pounds of potash. So that, based on its 

 plant-food content alone, a ton of such manure would be worth at least $2.50. But 



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