26 BULLETIN 1186, U. S. DEPARTMENT OF AGRICULTURE. 
WESTERN NORTH AMERICA. 
One of the grave problems now confronting the Federal and State 
Governments is the safeguarding of the five-leaved pines of the 
West from this European pest. Now that the disease has made its 
appearance in British Columbia and Washington, what will be the 
result? The final outcome is difficult to forecast, but it is certain 
that the western five-leaved pine forests are in grave danger. Ob- 
servations made in Europe upon the susceptibility of sugar pine, 
western white pine, and limber pine to the fungus showed that 
these trees are as readily attacked and as severely damaged by 
the white-pine blister rust as is the eastern white pine. It means 
that 5228,400,000** worth of growing timber is to become the prey 
to a very insidious and dangerous disease. A widespread attack 
in this region is imminent and threatens to bring immeasur- 
able loss to private owners as well as to the Federal Government. 
To judge from the severity of the disease on these species of pines 
in Europe, it is no exaggeration to predict that the presence of the 
blister rust in the Northwest threatens the future position of these 
valuable pine species in the timber markets of the world. 
DECIDED STEPS OF ACTION NECESSARY. 
The action demanded by present conditions in order to contro] the 
blister rust is summarized as follows: 
(1) Energetic control of the disease in the East by the general 
eradication of currants and gooseberries in pine-growing sections. 
(2) Prompt and decisive action to control the disease in the West. 
(3) Eradication of the cultivated black currant, the most suscepti- 
ble alternate host of the blister rust and the most active agent in its 
spread and establishment. : 
(4) Strict adherence to and prosecution of the quarantine laws 
prohibiting the shipment of five-needle pines and currant and goose- 
berry plants from infected territory. Also the continued enforce- 
ment of the quarantine placing an absolute embargo on foreign 
nursery stock, thus preventing the entrance of the blister rust and 
other pests from foreign countries. Conditions demand such action. 
The scope of the problem is more than regional or national; it is 
international. Neither evasion of the quarantines nor laxity in the 
prosecution thereof can be permitted. The lability is large and the 
hazard great. 
SUMMARY OF THE BLISTER-RUST SITUATION IN EUROPE. 
The white-pine blister rust was first discovered some 65 years ago 
on pine and currants in the Baltic Provinces of Russia. Six years 
later it was seen to attack seriously 30-year-old white-pine trees in 
Finland and was marked as a dangerous tree disease. It is difficult 
to state where the disease originated, but the facts available to the 
writer indicate that Russia was the original home and Pinus cembra 
its host. From there it migrated and gradually spread over western 
Europe. 
Its occurrence was noted with increasing frequency from 1880 to 
1900, particularly in those countries, such as the British Isles, Den- 
mark, Germany, and Sweden, in which plant pathology is carefully 
17 Estimate of the United States Forest Service. 
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