Abstract:

During 1990 and 1993, the author made dimensional measurement of the root rots in the internal part of the infected logs in Zhangguangcai moutain range. This paper made following analysis according to the shapes of these rots:①At cross section, where rot entered into the stem the rot became a circle and had a circumference parallel the growth ring; ②At vertical section, 84% of the rots were rectangualar and cuneiform (50% for each).It is concluded that:the root rot in the internal part of stem could not be said cone-shaped simply. Exactly, the root rot was cone-shaped in general, but In specific, it was ladder-cylind narrowing to the top.

Key words: Root rot stem internal, Following measure, Cone, Ladder cyiinder