6 BULLETIN 81, U. S. DEPARTMENT OP AGRICULTURE. 
York and Boston by departmental inspectors showed the presence of 
powdery scab in most of the arrivals from the Netherlands and in 
many of those from Belgium and Canada. The percentage of pow- 
dery scab varied from a trace up to 20 per cent or more. The scab 
was usually of the superficial type, though some advanced cases were 
found. Common scab was also present. 
It has been suggested since by the representatives of the Govern- 
ments of the Netherlands and Belgium that these infected potatoes 
may have originated in Germany rather than in their countries, and 
an examination of the situation has indicated that the original quar- 
antine order may not have provided sufficient safeguards against the 
transshipment of potatoes from Germany and other quarantined 
countries through Antwerp, Rotterdam, and other nonquarantined 
ports. 
In the situation thus presented, the Department of Agriculture 
had to determine promptly two points: (1) Is there danger that 
diseases present on imported potatoes will become established in 
American fields? (2) Is the powdery scab a new and dangerous 
disease requiring exclusion by quarantine ? 
POSSIBLE INFECTION FROM IMPORTED POTATOES. 
The greater portion of the foreign potatoes imported are intended 
for table purposes and are consumed in New York, Boston, and Phila- 
delphia, where it has been urged that by no possibility could infection 
reach potato fields. The facts, as determined by the Department of 
Agriculture, are that hundreds of thousands of bushels have been 
shipped from New York to interior points and that foreign potatoes 
have been sold as far west as St. Louis and as far south as New 
Orleans. This was particularly the case in 1911. There are abun- 
dant opportunities for disease germs on potatoes used for food to 
reach the land. Partially decayed or scabby tubers are sorted out 
by the retailers and disposed of for feeding to five stock, and manure 
thus infected is hauled to surrounding farms. Parings from the 
potatoes go into the family garbage can and find their way directly 
or indirectly to cultivated fields. 
A second avenue of infection is through the use of foreign potatoes 
for seed. It is now fairly well known that European varieties do not 
succeed in the United States and that the use of foreign seed is not 
profitable, yet the number of actual instances traced by the Depart- 
ment of Agriculture where European seed potatoes were purposely 
planted as an experiment or through ignorance of their lack of value, 
or where unscrupulous dealers had sold foreign stock as domestic, is 
large enough to show that the danger from this source is a real one. 
Canadian potatoes are valued for seed purposes and were being 
bought in large quantities when the quarantine was laid. 
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