use of manure treated with borax as herein recommended. When applied at
the rate of 15 tons per acre it appears that no injury as a rule will
follow. Some crops are more sensitive to borax than others, and also the
tendency to injury appears to vary on different soils. It is necessary,
therefore, to repeat the warning issued in connection with a previous
bulletin[11] on this subject, that great care be exercised, in the
application of borax, that the manure does not receive more than 1 pound
for every 16 cubic feet, and that not more than 15 tons of manure so
treated are applied to the acre.

In view of the possible injury from the borax treatment as a result of
carelessness in applying it, or from other unforeseen conditions, it is
recommended that horse manure and other farmyard manures which are to be
used as fertilizer be treated with hellebore. Borax, on the other hand,
is such a good larvicide that it call be used with advantage on the
ground of soil-floor stables, in privies, on refuse piles, and on any
accumulations of fermenting organic matter which are not to be used for
fertilizing purposes.

[Footnote 11: Department Bulletin 118, U. S. Department of Agriculture,
p. 25.]


TREATMENT WITH CALCIUM CYANAMID AND ACID PHOSPHATE.

Many experiments with mixtures of commercial fertilizers were tried to
determine whether fly larvæ would be killed by any substance the
addition of which would increase the fertilizing value of the manure. A
mixture of calcium cyanamid and acid phosphate was found to possess
considerable larvicidal action. Several experiments showed that 1/2