INOCULATION WITH PINE TWISTING AND SCOTS PINE BLISTER RUST 323 



KLINGSTROM: I will try to look for that. 



BINGHAM: Allan, would you care to comment on van der Kamp ' s finding 

 reported in his 1968 or 1969 bulletin in respect to the fact that he 

 could account for only 10 percent of the lesions in Scots pine blister 

 rust by wounding of the bark or stem directly? The remainder is a little 

 mysterious regarding exactly what he meant. They seemed to have occurred 

 through wounded or unwounded needles. 



KLINGSTROM: Yes, it is not too easy to comment on that, but it may 

 be that he has, perhaps, a strain of Periderrrtium which is very infectious. 

 Or, he may have had pines which were very susceptible. All the older 

 literature says that you have to wound the seedlings and you have to 

 wound the shoots and so on. I have made tens of thousands of inoculations 

 and I have only had success when I wounded the shoot. I shouldn't say 

 that van der Kamp is wrong. He has evidently worked with other materials 

 or he may have wounded the leaves a little bit, because the wound can be 

 very very small. When I apply the drop of spores I have tried to make 

 just one puncture, five punctures, ten punctures. I have always had the 

 greatest success with only one puncture, since it is just a very little 

 wound which is necessary, and the wound can be of any size. 



