Journal of Forest Science, 2003 (vol. 49), issue 6

LANDSAT and its application to evaluate the dynamics of the health condition of birch stands

E. Kula, M. Stoklasa

J. For. Sci., 2003, 49(6):241-251 | DOI: 10.17221/4698-JFS  

Methods were elaborated that would specify factors affecting the accuracy of the output of LANDSAT satellite images used to evaluate the dynamics of changes in the health condition of birch stands. In the period of investigations, in 1994-2000, the foliage of birch stands was very thin as a consequence of the large-scale absence of flushing in 1997. The output of this method is also specification of the degree of foliage of birch trees based on the altitude, stand age and forest site types in the air-polluted area of the Krušné hory Mts. (Northern Bohemia). These methods can be applied to other broadleaved stands.

Diapause of Cameraria ohridella Deschka et Dimic and its impact on the species population dynamics

T. Samek

J. For. Sci., 2003, 49(6):252-258 | DOI: 10.17221/4699-JFS  

Cameraria ohridella Deschka et Dimic is a polyvoltine species which can complete under suitable conditions the development of as many as three generations a year. In the Czech Republic, however, the third generation suffers from high mortality due to the shortage of food and later also unfavourable weather. If the third generation is not completed the population continuity is ensured by diapausing pupae occurring in each generation. The number of diapausing pupae is determined by the actual abundance of the species and thus also by the actual damage to the horse chestnut (Aesculus hippocastanum L.) foliage. Relationships of the parameters...

Distribution of sweet chestnut Castanea sativa Mill. in the Czech Republic

P. Haltofová, L. Jankovský

J. For. Sci., 2003, 49(6):259-272 | DOI: 10.17221/4700-JFS  

Sweet chestnut Castanea sativa Mill. is an introduced species in the Czech Republic. It is recorded roughly from 300 localities. To the end of 2002, the occurrence of chestnut was verified at about 140 macrolocalities. The most northern locality recorded so far was Choustníkovo Hradiště in the region of Hradec Králové. Chestnuts occur generally to an altitude of 500 m (80% of all examined localities), at higher altitudes they suffer from climatic extremes particularly late frosts. The occurrence of chestnut was recorded at 27 localities (ca. 20% localities under investigation) where altitudes exceed 500 m. The highest location of chestnut...

Impact of skidder and high-lead system logging on forest soils and advanced regeneration

M. Modrý, D. Hubený

J. For. Sci., 2003, 49(6):273-280 | DOI: 10.17221/4701-JFS  

The applied skidding technology strongly influences the impact of harvest on the ecosystem and success of natural regeneration. The impact of skidder SLKT 81 and high-lead system Larix 3T on forest soil and natural regeneration was compared under analogical site and stand conditions in a production beech forest in the environs of Brno, Czech Republic. The skidder was found to have greater effects on the soil surface consistency, soil properties and natural regeneration than the high-lead system operations. Although high-lead system operations are more friendly to all parts of forest ecosystem, the skidder may not cause excessive damage when applied...

Effect of negative factors on the use of oak and beech for decorative veneers

P. Král, J. Hrázský

J. For. Sci., 2003, 49(6):281-289 | DOI: 10.17221/4702-JFS  

The paper summarizes results of an institutional research aimed at the analysis of relationships between the quality of decorative veneers of oak and beech and negative factors decreasing the use of veneers. Effects of factors were assessed in the preparation, storage and protection of a raw material, treatment of logs before slicing and stay-log cutting and in the manufacture of veneers proper. Intensity of spraying was measured, protection of raw material during storage and regimes of hydrothermic preparation were assessed. Qualitative yield was determined in 386 logs of a diameter from 34 to 66 cm comparing four methods of cutting: half-round cutting...