1871. 



NEW ENGLAND FARMER. 



317 



EFFECT OF COMMERCIAL FERTILI- 

 ZERS. 



DOES THEIR USE TEND TO THE IMPOVERISHMENT OF 

 THE SOIL? 



I have a piece of ground of light soil that will 

 produce only twentj' bushels of potatoes, but by 

 using phosphate I got seventy bushels. Does the 

 phosphate alone make the tifty bushels, or does it 

 serve to draw enough froiu the latent properties 

 of the soil to make the crop ? and if so, is not my 

 land poorer for it .=" Reauek. 



Rejiakks. — The questions of our corres- 

 pondent are somewhat searching ones. The 

 last two (luestions may be answered by the 

 monosyllable, Yes. That brief reply, how- 

 ever, would not give a clear and satisfactory 

 solution of the case. The application of the 

 phosphate may be explained by a homely illus- 

 tration. In drawing a load, if the whip is ap- 

 plied to the horse, the load is moved faster, 

 but the power of the horse is sooner ex- 

 hausted. So if a person uses a stimulant, he 

 may accomplish more labor of brain, or of 

 muscles and sinews, for a short period, than 

 he could have done without it ; but the power 

 of brain and the other organs would sooner 

 yield to the pressure. 



It was not, we conceive, "the phosphate 

 alone which made the fifty bushels of pota- 

 toes," but an accelerated action, caused by the 

 phosphate, of all the elements in the soil which 

 go to make up the potato. These elements 

 were in the soil, in small degree perhaps, and 

 dormant for want of some stimulating cause. 

 They were not sufficient in quantity, or vigor, 

 or were not sufficiently comminuted and min- 

 gled with each other to enable them to act in 

 conjunctio.n with the elements of the atmos- 

 phere, and so the crop was light. 



"The successful growth of a crop or a field, 

 proves that it has found in the air and in the 

 soil the atmospheric and mineral constituents 

 of its food in the proportions suitable for its 

 nourishment. The failure of a crop on the 

 same field, indicates that in the soil there is 

 something wanting which is necessary for its 

 growth. In case of failure, therefore, we 

 must look to the ground ; the atmosphere is 

 always ready to supply its portion of plant 

 food." It is "nearly invariable in its compo- 

 sition at ^11 times -and over all parts of the 

 earth's surface. Its power of feeding crops 

 has, therefore, a natural limit, which cannot 

 be increased by art. 



"The soil, on the other hand, is very varia- 

 ble in composition and quality, and may be 

 2 



enriched and improved, or deteriorated and 

 exhausted." 



A soil may possess all the elements for plant 

 nutrition and still not be a prolific one. This 

 may come from several causes. First, 



From too Dry a Condition of the Soil. 

 If rain has been withheld for a long time, 

 and evaporation excessive, there would be lit- 

 tle action in the soil, and crops would fail. If 

 it were deep and rich in nitrogenous matter, 

 it would hold out longer than a thin and poor 

 soil, but would finally cease to sustain plants 

 as action in it grew less and less. 



The Effect of too much "Water. 



The effect of a superabundance of water 

 would be much the same as a want of it ; each 

 would prevent action in the soil, and hence no 

 nutrition would be supplied to the plants stand- 

 ing in it. The same conditions would affect 

 animal life in a similar way. Water and air 

 are indispensable to man, but if the former 

 were present with him in great excess, or the 

 latter were withdrawn, his vital functions 

 would soon cease, and he would die. The 

 same principles seem to us to be involved in 

 plant and animal life. 



Again, very much will depend upon the me- 

 chanical condition of the soil. The question 

 naturally arises. Was the land planted with 

 potatoes in the same condition, with the ex- 

 ception of the addition of the phosphate ? 

 One hundred pounds of a fertilizer applied to 

 a soil that is fine would probably be as effica- 

 cious as 200 or 300 pounds on a coarse lumpy 

 soil. Baron Liebig explains this point so 

 clearly that we give his words as follows : 



"The rapidUy with which a substance, such as a 

 piece of sugar, is dissolveti by a tluid, is in propor- 

 tion to its state of division. By pulverization its 

 surface is increased, and consetiucntly the number 

 of points augmented, which, in a given time, arc 

 brought in coTitact ^ith the di>solving fluid. In 

 all chemical processes of this kind, the action pro- 

 ceeds from the surface. An element of food in tlie 

 soil acts by its surface, the portion beneath the sur- 

 face is inactive, because it cannot be dissolved. Its 

 effect, within a given time, increases with the quan- 

 tity tiiken up by the plant during that time. Fifty 

 pounds of bones may in one year produce, accord- 

 ing to their state of divi?ion, the same etfect as one, 

 two or three hundred pounds coarsely ground. 

 In the latter state it is by no means inefficient ; but 

 to act, that is, to become soluble, it requires a lon- 

 ger time. The effect produced by it is smaller, but 

 it continues longer. 



"To understand correctly the effect of tlic soil 

 and its constituents on vegetation, we mu^;t keep 

 steadily in view the fact, that the elements of tbod 

 present in it always possess within theinselves»ac- 

 tive powers, but they are not always in condition to 

 exert this power. They are ready to enter mto cir- 



