Canadian Forcstrij Journal, Fchruaii/, 1917 



971 



iircs have been or are available for 

 coping wilh this disease, and what 

 fiirlher steps should be taken, if so 

 deemed expedient. 



On learning that suspected pine 

 seedlings had been introduced into 

 Canada from abroad, this source of 

 danger was promptly eliminated. The 

 Dominion Government prohibited the 

 importation of all five-leaved pines 

 into Canada from anywhere abroad. 

 Similar action has also been taken 

 by the United States' authorities. 

 We are, then, assured that no more 

 diseased pines will reach this coun- 

 try, or the continent of America, in 

 future. 



We in the Dominion of Canada, 

 are in a very fortunate position con- 

 cerning federal legal enactments di- 

 rected towards the control of de- 

 structive insects, pests, and diseases. 

 Those familiar wdth the general reg- 

 ulations under the Dominion De- 

 structive Insect and Pest Act will 

 realize that we already possess wider 

 powers under this Act than perhaps 

 any other country in the world. But, 

 before bringing legislative activities 

 to bear, the preliminary work just 

 referred to must be accomplished, 

 and the sooner this is done, the better. 



Eradication of Pine. 



As far as blister rust is concerned, 

 it is no question, in the present state 

 of our knowledge, of treatment of 

 infected pines, but of eradication of 

 diseased trees. We are of the opin- 

 ion that the distribution of white 

 pines from nurseries within danger 

 zones should be promptly prohibited, 

 since incipient attacks, as already 

 stated, may escape notice during in- 

 spection, and, moreover during the 

 incubation period no reliable signs 

 are exhibited by infected pines. Such 

 incipient infections as represented by 

 these stages, distributed by seedling 

 pines, would only result in a wider 

 spread of the disease, and render 

 the problem of protection from dis- 

 eases a very doubtful, or at any rate, 

 very difficult matter even to the train- 

 ed official. 



Stop Distribution'^ 



The issue raised here is, shall we 

 permit the distribution of white pine, 



pending the settling of the question 

 of the extent of the menace from 

 this disease, or shall we take initial 

 precautions and refrain from dis- 

 tribution, until the true nature of 

 the threat from this scourge has been 

 ascertained — in other words, till we 

 know if the menace to American white 

 pines will turn out to be as serious as 

 it has proved itself to European white 

 pines, and one which has seriously 

 affected the use of white pine for 

 afforestation purposes in northern 

 Europe? 



I believe, from frequent discussions 

 of the subject of control of Blister 

 Rust in Canada, that we are agreed 

 that extermination of suspected plan- 

 tations, if faithfully carried out, and 

 if coupled with replacement of the 

 same by healthy trees will do more 

 towards stamping out the disease 

 than periodical and difficult — and, 

 at that, inefficient — inspections. 



Inspection Very Costly. 



Periodical inspection of nurseries 

 has been often recommended. But, 

 from actual experience, it has been 

 learned that the closest inspection 

 possible will not reveal all infected 

 trees, and new infections will be 

 found year after year. In the United 

 States, where the disease is widely 

 prevalent, it has been found that, in 

 many cases, the cost of continued 

 inspection will more than replace the 

 diseased plantations with healthy 

 trees, and that this latter policy would 

 be more economical than the con- 

 tinuation of periodical inspection. 



At least three states — New Jersey, 

 New York, and Connecticut — have 

 already destroyed entire shipments 

 of white pines, when the disease w^as 

 found in them. The destruction of 

 infected plantations is the logical 

 continuation of this policy. It will 

 rid the country of the disease, and is, 

 apparently, the only sure method 

 of doing so. 



Whole Grove Infected. 



It is no easy matter to stamp out 

 the disease once it appears in native 

 pines. I recall one case at Fonthill, 

 Ontario, where the disease appeared 



