THE AMERICAN BOTANIST 129 



of the white pine blister is some species of currant, wild or 

 cultivated. Spores from the pine set up their growth on 

 currant leaves and after a time produce new spores which can 

 cause further disease in the pines. It is believed that the spores 

 from the plant on the pines cannot directly spread the disease 

 to other pines but must first pass through the stage of growth 

 on the currant. If this is so, we have one means of control which 

 is absent in the case of the chestnut blight, for if all the currants 

 near pine trees are rooted up, the disease is likely to die out 

 for want of a bridge from one generation on the pine to another. 

 Unfortunately the destruction of the currants runs counter to 

 the nurseryman's interests again, and it becomes a question in 

 some localities whether to save the currants and let the pines 

 die, or to save the pines by uprooting the currants. 



While the white pine of the eastern States is the only 

 species threatened at present, the disease is believed fatal to all 

 members of the white pine group— that is, to all pines with five 

 needles in a bundle. There are several species of this kind in 

 the western part of our country and it is important to check the 

 disease before these, also, are attacked. It is expected that the 

 national government will appropriate a certain sum for the 

 eradication of the disease and several States in which the forests 

 are threatened will probably do likewise. It will be only by the 

 most prompt and energetic action that the trouble may be con- 

 trolled. 



