MITE PINES ASIA: ARMANP AND KOREAN PINE 



131 





Figure 6. Form of bark of Pinus '<cr-o.ier.sis on A) 100-year-old 

 tree from a natural stand on Mt . Sorak and B) 40-year-old tree 

 from a plantation at Kwangyang. 



lath during the first summer, and thinning to 400 seedlings/m 2 of seed 

 bed in the fall. The stock is removed from the seed beds as 2-0 seedlings 

 between 12 and 15 cm tall. 



The form and distribution of the root system varies with the soil 

 characteristics. It has several (usually three to five) large roots 

 stretching downward and outward in the soil giving the tree a firm anchor 

 under most conditions. No serious root damage in the nursery or in 

 plantations has so far been recorded, except a slight amount by cutworms 

 in the seed beds. 



The common practice is to plant 2-0 or 2-1 seedlings at a spacing of 

 2 m. Growth is rather slow during the first 3 to 5 years after planting, 

 but it gradually improves and thinning is needed by 20 years. Fifty to 

 80 years is the usual rotation for producing saw timber. Due to very 

 poor self-pruning, a regular pruning practice is needed for production of 

 knot-free logs (Fig. 7). 



With regard to pests and disease, the black tipped sawfly {Acantholyda 

 posticalis Mats.) has caused some damage in a middle-aged plantation (Lee 

 and Cho, 1959) . 



Blister rust damage was first reported in 1937 (Takagi , 195") in an 

 8-year-old plantation in Kyunggido Province of Korea. Takagi reported 

 that around 650 planted stocks expressed blister rust symptoms on their 



