132 



S. K. HYUN 



Figure 7. A thinned plantation 

 of P. koraiensis 40 years old. 



stems. The rust was identified as Peridermium strobi , the aecial stage 

 of Cronartivm ribioola J. C. Fisch. ex Rabenh. by Professor Hiratsuka 

 (Takagi, 1937). Dr. Takagi failed to find any Ribes spp. around the 

 plantation. 



Forest pathologists of the Forest Experiment Station of Korea recently 

 reported (not published) damage to a P. koraiensis plantation by blister 

 rust in Kangwondo Province. Plantations 5 to 9 years old and 60 ha in 

 total area located in 3 different sites in Pyongohang County, Kangwondo 

 Province were damaged by blister rust (Fig. 8, 9, and 10). The pathologists 

 reported that 35% of the planted trees were seriously damaged by this 

 disease. However, no blister rust was found in a nearby 15-year-old 

 plantation during 3 years of continuous observation. So far they also 

 failed to find Ribes spp. growing around the infected area. 



GROWTH PERFORMANCE 



Growth in the natural stand is quite slow, probably because of cold 

 climate and dry soil. It takes 5 to 30 years to come up to a breast height 

 according to the site condition. Average growth performance of single 

 trees in a natural stand growing on rocky shallow soil is given in 

 Figs. 11 and 12. 





