Rozsirenie Cervca Bukoveho (Cryptococcus fagi Bärensp.) v Bukovych Porstoch

1998

S. 73-83

6 Lit. Ang.

Unselbständiges Werk

200073044

Author gives some information on beech scale (Crytococcus fagi Bärensp.) and its occurence in beech stands. There are presented factors which influence population density and distribution of beech scale. Most important primary factor seems to be chemical composition of beech bark tissue. This factor is refelcted in visible growth characteristics of tree. There are two examples of beech stands (Stagiar valley and Bien valley near Zvolen) where variability and distribution of beech scale was observed in association with tree diameter (d13) distribution. There are presented two methods of evaluation of degree of infestation of beech trees and whole forest stands. The first method is direct counting of colonies of beech scale and enumerations of degree of infestation as density of beech scale colonies on 1 dm¬. The second method is visual assessment of degree of infestation by one of five degrees of infestation. High variability of infestation of trees in both stands was found. Relations between beech sclae density and tree diameter (d13) was found only in case of close relationships of characteristics of chemical composition of bark tissues and tree diameter.