솔껍질깍지벌레(Matsucoccus thunbergianae)의 수령에 따른 피해율은 7년이상 22년까지의 수령에서 피해율이 높았고, 피해목의 피해정도에 따른 자연부유균의 침해율에서 균사의 확대가 최대에 달하는 발병정도가 7정도에 이르기까지의 기간은 100% 고사목에서는 48일이, 80% 이상 고사목에서는 54일이, 40~50% 고사목에서는 약 75일이, 그러나 10% 이하 고사목과 무피해목에서는 80일 이상에서도 발병정도 3~4 정도였다. 피해목의 년륜폭은 무피해목 3.5cm 에 대하여 100% 고사목 0.77, 80% 고사목 0.88, 40~50% 고사목 1.22, 10% 이하 고사목은 1.37로 좁아졌고 피해정도에 따른 단위면적당 세포수도 피해가 심할수록 적어졌고, 함수율은 피해가 심할수록 높았으며, 휨강도는 낮아졌다. 또한 1% NaOH 추출물도 적었다.

The damage rate according to the age of black pine trees in the Black pine bast scale, Matsucoccus thunbergianae was high from 7 to 22 year old trees. According to damaged degree of damaged trees, it showed great difference in infection rate of saprophitic fungi. The period until the developmental degree of saprophitic fungi became maximized degree of 7 was required about 48 days in dead tree of 100 percent, about 54 days in one of above than 80 percent, about 75 days in one of 40~50 percent, but the dead tree less than 10 percent and health tree was retained the 3~4 developmental degree of saprophitic fungi, after 80 days. The ring width of damaged trees showed as follows. The non damaged trees was 3.52 cm, 0.77 cm in the damaged trees of 100 percent, 0.88 cm in the ones of 80 percent, 1.22 cm in the ones of 40~50 percent and 1.37 cm in the ones of les than 10 percent, respectively. Number of cells per unit area was smaller in the case of greater damaged trees, gradually. Also moisture content was very high in greater damaged trees, and bending strength was lower. Extracts by the one percent NaOH showed a small amount.

• 김규진
• 김종완
• 임기표