February, '14] ORTON: PLANT QUARANTINE PROBLEMS HI 



mains to be worked out. The very existence of the parasites of greatest 

 peril has often been discovered after it was too late to prevent their im- 

 portation, as in the case of the chestnut bark disease. Not only domes- 

 tic surveys of insect and fungous parasites are necessary, but foreign 

 surveys as well, and there is particular need of information from the 

 lesser known continents of South America and Asia. 



That the parasites of other continents are most dangerous is abun- 

 dantly proved by the experience of Europe with the Phylloxera, the 

 black rot, and the mildew of the vine, and more recently with the 

 gooseberry mildew, and by our experience wdth the imported gypsy 

 moth, the brown-tail moth, the codling moth, the asparagus rust, the 

 hollyhock rust, and the late blight of potato. Nature tends to pre- 

 serve an equilibrium between native plants and their parasites, but 

 when this is disturbed by man, through the chance transfer of a para- 

 site, the invader, if a fungus, finds relatives of its original host, which 

 lack resistance to its attacks, or, if an insect, it leaves its own natural 

 parasites behind and spreads in the new field to an extent never known 

 in its native habitat. 



These facts greatly complicate our task, for it is hard to foresee 

 where the dangers lie. To secure concerted and cooperative action in 

 all countries would greatly facilitate the w^ork, and it is an encourage- 

 ment to know that the need for such international efforts is being more 

 strongly felt in Europe, and that a movement which has been gaining 

 headway for many years promises to result finally in definite action 

 in connection with the International Institute of Agriculture at Rome. 



THE MOVEMENT FOR INTERNATIONAL PHYTOPATHOLOGY 



The terra phytopathology in Europe is used to include insects as 

 w^ell as fungous and other troubles, since the field of work of the ento- 

 mologists there has not been as clearly separated from pathology as in 

 the United States. The history i of this international movement dates 

 back at least to 1880, when Dr. Jacob Eriksson, the eminent Swedish 

 botanist, laid a plan for international action before the international 

 congress for agriculture and forestry at Vienna. In 1891, at the 

 International Congress at The Hague, Professor Rostrup called atten- 

 tion to the need of means for preventing the introduction of epidemic 

 diseases through tha importation of living plants or seeds infected 

 by parasites. In 1900, Eriksson presented the matter to the Fourth 

 International Congress for Agriculture at Paris, and again in 1903 



1 Louis Dop. Rapport sur la cooperation international dans la lutte contra les 

 maladies des plantes, presente au congress international de pathologic comparee. 

 Paris, 1912. 



