16 FARMERS’ BULLETIN 679. 
Bacteriological studies of the treated piles proved that the bacteria 
were not injured nor their development retarded, and chemical analy- 
sis showed that the composition of the manure was unaltered. Fur- 
thermore, several field tests were made in growing cabbages, turnips, 
lettuce, potatoes, wheat, and a few other crops on plats which had 
been fertilized with hellebore-treated manure, with the result that 
there appeared no injury whatever that could be ascribed to the use 
of this substance. The only possible objection to the use of hellebore 
seems to be the possibility of poisoning farm animals, as might 
happen if, for example, the barrel or tank in which the stock solution 
was prepared were left uncovered in an accessible place. It is quite 
safe to say that chickens will not-be injured by pecking at hellebore- 
treated manure. This has been tested carefully. Hellebore can be 
obtained both in ground and powdered form, but the powdered form 
gives the best results in the destruction of fly larve. It costs from 
12 to 16 cents per pound and under normal conditions can be obtained 
in large lots for 10 cents or less per pound. It is estimated that the 
cost of treating horse manure with hellebore will be a little over 1 
cent for every 2 bushels. It will be of interest to the agriculturist to 
know that in applying hellebore to manure he is adding a substance 
which contains fully 1 per cent of nitrogen. 
TREATMENT WITH POWDERED BORAX. 
Another chemical found to be even more effective as a larvicide is 
powdered borax. This is an inorganic substance, available in com- 
mercial form in all parts of the country. It has the advantage of 
being comparatively nontoxic and noninflammable and is easily 
transported and handled. The minimum amount necessary to kill fly 
larvee was found to be 0.62 pound per 8 bushels of manure, or about 
1 pound per 16 cubic feet. Best results were obtained when the 
borax was applied in solution, or when water was sprinkled on after 
the borax had been scattered evenly over the pile. Borax is not only 
effective in killing the larve, but when it comes in contact with the 
eggs it exerts a toxic action which prevents them from hatching. 
When applhed at the rate of 1 pound to 16 cubic feet it was found to 
kill about 90 per cent of the larvae, heavier applications killing from 
98 to 99 per cent. 
Borax had no injurious effect on the composition of the manure; 
in fact, in some cases the ammonia and water-soluble nitrogen seemed 
to be increased; nor was there any permanent decrease in the number 
of bacteria. Borax-treated manure was less subject to the growth of 
molds and consequent firefanging. Now, although borax does not 
have any deleterious effect on the chemical composition of manure, 
yet when added to the soil with the manure it acts directly on plants, 
