AMERICAN FORESTRY 



necessary trees could not be obtained in this country at 

 a reasonable price and, as a result, large quantities were 

 imported and scattered in a thousand places. Unfor- 



Photograph by S. B. Detwilcr. 



GIRDLED BY BLISTER DISEASE 



A native white pine at Kittery Point, Maine, with the base and lower side branches 

 girdled by the blister rust. The quarter-acre plot in which this tree stood 

 showed S8 per cent of trees infected in November, 1910. Twenty-six per cent 

 of the trees were dead. 



tunately, some of these trees were diseased and we now 

 must decide what we are going to do about what President 

 Pack so well calls "A Bandit from Abroad." 



Let us take a lesson from some of these many unfortu- 

 nate circumstances. Why not meet the situation frankly? 

 We must stop the spread of this disease. It can only 

 be accomplished through eradication and control measures. 

 We cannot fairly ask the farmer to give up all his currants 

 and gooseberries that the forester may utilize his soil 

 for growing pine. We must both of us make sacrifices. 

 In places, pines will have to be removed as part of the 

 control plan. We cannot now say where the immune 

 strips are to be placed. The extension of white pine plant- 

 ing, under present conditions, may further the spread of 

 the disease as well as make the control measure more dif- 

 ficult. The problem is difficult enough as it to-day exists. 



A few years more of idleness of these soils is notliing 

 in comparison to the future safety of white pine. We have 

 not gained but rather lost through past haste. Wait until 

 we first fully know where "we are at." 



A study to ascertain the extent of the disease, loca- 

 tion of different kinds of soil, also distribution of pine, cur- 

 rants and gooseberries, will add so materially to our 

 knowledge that future plans can then be formulated. 



For the time being, we should expend our energies in 

 field investigations, control work and education of the 

 public. 



The general progress of reforesting need not be seri- 

 ously interfered with because we may direct our energies 

 to planting lands not best adapted to white pine with 

 suitable species. 



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I THE PINE BLISTER DISEASE PROBLEM AS A WHOLE | 



I Dr. Haven Metcalf, in Charge Office of Forest Pathology, U. S. Dept. of Agriculture 1 



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T 



HE white pine blister disease has invaded America 

 and dug itself in. The earhest importation of white 

 pine nursery stock that we have been able to trace 



dates back only to 1899, but in this time the disease has 

 become generally prevalent upon gooseberries and cur- 

 rants in New England, and at many points has established 





Photograph by J. Franklin Collins. 



IN A BADLY INFECTED AREA 



This tree, photographed with a white cloth behind it to show the infection, had 

 its main stem and many branches girdled by the pine blister disease. It is in 

 a four-acre plot in Maine. In November, 1916, 87 per cent of the trees on the 

 plot were infected and 16 per cent were dead. 



Photograph by J. Franklin Collins. 



WHERE SPORES WERE PRODUCED 



Native white pine at Kittery Point, Maine, showing the main stem and many 

 side branches infected. The rough bark on the main stem and at the bases of some 

 side branches show that the disease has produced spores during the past season. 



