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HARUVOSHT SAHO 



potentiality of this species. As a result many more test plantations 

 have been established over the years. Nowadays, P. strobus is the 

 commonest foreign forest tree species planted in the northern part of 

 Japan, especially in Hokkaido. These plantations are, presumably, free 

 from the white pine blister rust, caused by Cronartium ribiaola J.C. 

 Fi srh . ex Pahpn^ , 



Among the introduced white pines, P. strobus has given the best 

 results in Japanese plantations. Our foresters now have had plenty of 

 experience in planting this species. If, over time, P. strobus continues 

 to escape the white pine blister rust, this species can be planted over 

 a much larger area in the northern half of Japan. 



Performance of P. strobus in some of the many Japanese plantations 

 of the species is shovvn in Table 1. Figure 7 shows the earliest planta- 

 tion established at the Tokyo University Forest in Hokkaido in 1917, and 

 Figure 8 a 15 -year-old plantation on the same Forest. 



Figure 7. A 1917 planta- 

 tion of Pinus strobus at 

 the Tokyo University Forest 

 in Hokkaido, Yamabe, 

 Furano . 



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