18 DIRECTOR’S REPORT OF THE 
Sporotrichum bud-rot of carnations.— This disease, previously 
known only in Nebraska, recently appeared in some New York 
greenhouses. The Botanist and one of the Assistant Entomologists, 
working in co-operation, have made a considerable study of it, the 
investigations being reported in Technical Bulletin No. 7. The cause 
of the disease was proven to be a fungus, Sporotrichum poe Pk. 
This fungus is found in the decayed tissue of diseased buds in con- 
stant association with a peculiar mite which, apparently, serves as a 
distributor of the fungus. The mite was identified as Pediculopsis 
graminum Reut, a species heretofore unknown in this country, but 
in Finland recognized as one of the chief agents in the production 
of a common grass disease called “ Weissahrigkeit.” June grass 
in New York is abundantly affected with the same disease which 
is here known is “ silver top.” The fungus and mite have been 
found, frequently associated, on June grass affected with silver 
top, but their relation to that disease has not been investigated. 
DEPARTMENT OF CHEMISTRY. 
Methods of paying for milk at cheese-factories—This subject is 
one of fundamental importance to dairymen who produce milk for 
cheese-making. This Station has given the matter more extensive 
and thorough study than any other institution, having previously 
published two bulletins (68 and 110) in relation to it. As many 
as six different methods have been proposed, which may be grouped 
under the following general divisions: (1) On the basis of the 
weight of milk; (2) on the basis of milk-fat; and (3) on the basis 
of the yield of cheese. ‘The first method has been proved beyond 
all question to be unfair, because milk varies greatly in its cheese 
producing power. It has been shown that in different milks the 
yield of cheese from 100 pounds of milk may be as low as 8 pounds 
and as high as 13 pounds. The yield of cheese might be supposed 
to furnish a fair basis, but it has been proved that cheese made 
from milk rich in fat is superior in quality and value to cheese 
made from milk poorer in fat. When milk is paid for on the basis 
of its fat content, the yield, composition and quality are all taken 
into consideration. While a pound of fat in rich milk is equivalent 
to less cheese than a pound of fat in poorer milk, owing to the 
somewhat larger relative amount of casein in the latter, the quality 
of cheese made from richer milk is enough better to make up for 
this difference in yield in relation to milk-fat. Besides being the 
most fair basis, when yield and quality of cheese are considered, the 
