ENDOTHIA CANKER OF CHESTNUT 605 
possible. No elaborate organization has been attempted and no large 
sums of money have been appropriated for these operations. The regular 
authorities are in charge of the work. The Office of Forest Pathology 
at Washington is still maintaining research work on the disease and has 
employed S. B. Detwiler, formerly in charge of the field operations in 
Pennsylvania, to check the results of the cutting-out done in western 
Pennsylvania. The report on this work is soon to be published (Detwiler, 
1914). North of Maryland no attempt is being made to control the 
disease. 
GENERAL DISCUSSION OF CONTROL MEASURES 
Exclusion measures 
In regions still unaffected the consideration of exclusion measures is 
highly important. Diseased nursery stock has been proved the most 
dangerous means of introduction of the fungus into new localities. The 
original spot infections in this country were, without much doubt, started 
from diseased nursery trees shipped from the Orient. Five out of nine 
of the spot infections in western Pennsylvania were traced to diseased 
nursery stock. The only spot infection known in western New York — 
at Penn Yan — was in an orchard. 
In order to prevent the shipment of diseased stock the trees should be 
inspected when they are packed and again when they reach their des- 
tination. A blanket certificate issued yearly to nurseries is worthless in 
the case of this disease, as with many others. As a part of the control 
measures instituted by the Pennsylvania Commission, all nursery trees were 
inspected and tagged individually before packing. The inspection of trees 
at their destination is not always sure to exclude diseased trees, for 
incipient infections are likely to be overlooked. 
Because of the uncertainty of inspection of shipments and the extreme 
virulence of the parasite, it seems highly desirable that an absolute 
quarantine be placed on the affected region of the eastern United States, 
which would prevent the shipment of chestnut stock outside the prescribed 
limits. This would protect outlying or distant parts of our own country 
and would aid foreign countries in excluding the disease. It is especially 
incumbent on foreign countries that have chestnut to protect, to take the 
most rigid measures in order to prevent this disease from gaining a foot- 
hold. 
The fact that diseased nursery stock is not the only means of transport- 
ing the fungus from an affected region must not be overlooked. Parts 
of diseased trees barked or unbarked may serve to carry the fungus. 
The following points show the danger there is in transporting unpeeled 
