HINTS ON SOILS AND FERTILIZERS 43 
tilizer per acre and get splendid results, while 
it is quite common for a potato grower in the 
State of Maine to apply a ton to the acre. 
There is a certain prejudice against these fer¬ 
tilizers among some farmers, but it may be 
said that the proper use of commercial fer¬ 
tilizers is a paying proposition. Some farmers 
believe that after a farm has once had com¬ 
mercial fertilizer applied to it, the land “burns 
out,” and that in order to get crops thereafter, 
he must continually resort to this form of fer¬ 
tilizer. This is a mistaken notion, however, 
because when these fertilizers are used intelli¬ 
gently they do not “burn out” the land, nor 
make it “lazy.” One good use of these fertiliz¬ 
ers was described in a previous chapter under 
the test plot method. When a land is deficient 
in nitrogen, for instance, is it not a far better 
practice to supply that lacking nitrogen in the 
form of some kind of fertilizer, than to try to 
farm the land with its lack of nitrogen? Any¬ 
one can see the common sense of the argument 
who is willing to reason from facts. 
We have discussed briefly, in the chapter on 
test plots something about commercial fertiliz¬ 
ers, but we will now endeavor to study more 
thoroughly this phase of soil improvement. 
We have already learned that nitrogen, phos-- 
phorus and potassium, otherwise known as 
potash, are the chief elements which the plants 
draw from the soil. Consequently, these three 
elements are the ones that must be replenished 
continuously. Let us take each of these ele¬ 
ments separately, and see how each one can 
be handled in the most successful manner. 
