抄録
In this paper, Japanese red pine (Pinus densiflora Sieb. et Zucc.) was blightened by two methods: girdling and inoculation with pine wood nematode (Bursaphelenchus xylophilus). The growth strain on surface, the distribution of moisture content of trees in the blighting processes and the distribution of growth stress within stems after felling sample trees were measured.
The results obtained are summarized as follows:
(1) At three weeks after inoculation with pine wood nematode, withered leaves started to appear in the lower part of the crown and the exudation of resin on the wounded bark stopped. It was thoght that trees inoculated with pine wood nematode started blighting on this occasion.
(2) The moisture content decreased around cambium at the start of blighting of trees treated by girdling and inoculation with pine wood nematode.
(3) The growth strain on surface showed a high value at the start of blighting of trees, but it was a passing phenomenon.
(4) In the trees treated by girdling and inoculation with pine wood nematode, the distribution of growth stress within stems differed from that of normal wood.
