L r  A
i g     ` . 56 _BuZZetin N0. 191.
_  Z p . { ing under brand names as mixed fertilizers. Acid phosphate
1 ~  ” f " “ is the basis of them. They usually contain 8 to 10 per cent i
  1 '_ _ fi phosphoric acid and sell for considerably more per ton, some-
i   t times nearly twice as much, as 16 per cent acid phosphate
; _   . ~ which contains twice as much phosphoric acid. Sixteen
  "  A _ per cent acid phosphate should not be considered a low grade A
; _ l   if V _ fertilizer simply for the reason that it sells for a lower price  S
A i fl ` per ton than certain mixed fertilizers, such as those discussed
.— 6 i 1 , V in the foregoing paragraphs; ‘ .
gl _... l { - What the farmer is actually concerned with is the cost per
  pound of plant foodcontained in fertilizers. The manufac- `
    y Z, · ture of such low grade mixed fertilizers is virtually an .
i `%  admission of the importance attaching to the use of phos-
l ‘._`   _ V ·_ _ phates. If mixed fertilizers are to be used onlyhigh grade
;___§__4 _ . _ mixtures should be employed; that is, such as contain high
  , _ percentages especially of phosphoric acid and nitrogen, for
   ‘ A the reason that the plant food contained in them is cheaper A
  than in low grade mixtures. Smaller amounts may be used
  1 thus saving drayage, freight and bagging charges.
  ` · The sale of low grade fertilizers will probably cease when '
  `»i1` ;   * A farmers quit buying fertilizers by brand names and at the
  j lowest price per ton regardless of composition. It is hardly Z
  A to be expected that,such fertilizers will not be offered for
  sale so long as farmers are willing to buy them.
  Out of such a maze of fertilizers offered, how is the farmer
  to choose for his needs, unless, he understands the funda- .
  mental principles of soil fertility and the nature of commer-
  cial fertilizers and fertilizing materials? It is clearly the
  duty of the Agricultural Experiment Station and all other
    ~ agencies for agricultural instruction to give him in as clear
  and simple manner as possible this information.
1*3]%.
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