8 TREATMENT OF: DAMPING-OFF IN CONIFEROUS SEEDLINGS. 
the seed, until it was thoroughly drenched, and the treatment was re- 
peated about a week after the seedlings came up. The treated plot 
was in excellent condition in December; there was a very good stand 
of fine, healthy seedlings and the soil was entirely free from alge and 
moss. The check plot, on the other hand, had practically no seedlings 
left, and the soil was green with alge and moss. 
This solution of sulphuric acid was applied to young seedlings ofa 
number of different species, and but one showed any ill effects. This 
was Norway spruce (Picea excclsa). It is not advisable to use an 
acid solution as strong as this upon the plants. Kraemer @ has shown 
that a solution of sulphuric acid at the rate of 1 to 500 is as strong as 
should generally be used upon plant tissues, and this is recommended 
rather than the much stronger one used in these experiments. For 
soil treatment the stronger solution will probably prove preferable. 
Approved: 
James WILSON, 
Secretary of Agriculture. 
WasuineTon, D. C., April 6, 1908. 

@\raemer, Henry. Dilute Sulphuric Acid as a Fungicide. Proceedings, 
American Philosophical Society, vol. 45, pp. 157-163, 1906. 
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