DANGEROUS INTERNATIONAL FOREST TREE DISEASES 25 



underway for several years and in Quebec tests of resistance of native 

 and European elm hybrids to the Dutch elm disease have been in 

 progress since 1956. 



Quarantine Measures 



The Destructive Insect and Pest Act (2) guards against the intro- 

 duction and distribution of destructive forest diseases and insects. 

 This Act is administered by the Plant Protection Division of the De- 

 partment of Agriculture which is empowered to quarantine any for- 

 eign disease that has not become widely distributed. Where a disease 

 is well established, the movement of host material may be restricted 

 to prevent the spread of the disease to other parts of the country. 

 Dutch elm disease is an example of a disease that has become per- 

 manently established. The importation of all plants and products 

 of Ulmus and Zelkova is prohibited unless the material has been kiln- 

 dried under specified conditions. To prevent the spread of the disease 

 within the country, the shipment of elm plants or logs from the east- 

 ern provinces of Ontario, Quebec, and New Brunswick to other prov- 

 inces is not permitted. 



These regulations are under constant revision according to circum- 

 stances. At present, for example, negotiations are under way to in- 

 clude specific clauses in the Act to prevent the introduction and spread 

 of certain diseases such as weeping canker (bacterial canker) of pop- 

 lar caused by Pseudornonas syrinqae. Suggestions for the improve- 

 ment of quarantine legislation and procedures are being submitted in 

 the general discussions in Session IV of this symposium. 



Literature Reviews and Publications of International 

 Interest 



Literature reviews of forest diseases are generally included as part 

 of publications reporting specific research. In addition, some recent 

 reviews include dwarfmistletoes (5), the diseases of lodgepole pine 

 (JO), the diseases of red and white pine {11), and general reviews (#, 

 9). A list of French and English names of tree diseases in Canada is 

 in press. The annotated list of diseases of Pinus now in preparation 

 will include the pertinent literature on this subject. Further reviews 

 of forest diseases are planned. 



A number of Canadian reports and publications are of interest to 

 pathologists in other countries. The Annual Report of the Forest 

 Insect and Disease Survey has already been mentioned. The Bi- 

 Monthly Progress Report of the Forest Entomology and Pathology 

 Branch is another publication that provides progress statements on 

 research underway at regional laboratories throughout Canada and in- 

 cludes a current list of scientific publications. An annual list of pub- 

 lications of the Forest Entomology and Pathology Branch on forest 

 diseases is also issued and copies of the listed papers, many of which 

 are of international interest, are available upon request, usually with- 

 out charge. 



Directory of Forest Pathologists 



A report has been prepared for distribution at this symposium list- 

 ing the names and research interests of forest pathologists of the 

 Forest Entomology and Pathology Branch, Department of Forestry. 

 In addition to this list of Department of Forestry pathologists, other 

 scientists working in the field of forest pathology in Canada are re- 



