Journal of Forest Science, 2003 (vol. 49), issue 8
Minimum area of forests left to spontaneous development in protected areas
S. Vacek
J. For. Sci., 2003, 49(8):349-358 | DOI: 10.17221/4709-JFS 
Search for ecological criteria for decisions on forests to be left to spontaneous development in specially protected areas is based on the knowledge of regularities of autochthonous or natural forests. They are mainly relative constancy of the species composition of communities, relative all-agedness, relative equability of growing stock and relatively small areas of the particular developmental phases and stages. They will lead to the maintenance of ecological autonomy and equability of natural forest; their basic condition is to determine a minimum range (area) of forest stand when the populations are still maintained by autoregulation. The output...
Biology and harmfulness of Eriosoma (= Schizoneura) ulmi (L.) (Aphidinea, Pemphigidae) in elm
J. Urban
J. For. Sci., 2003, 49(8):359-379 | DOI: 10.17221/4710-JFS
The paper deals with the occurrence, development, natural enemies and harmfulness of a heteroecious aphid Eriosoma (= Schizoneura) ulmi (L.) which showed outbreaks in elm Ulmus glabra Huds. in Moravia in 2002. At main localities under study in Bílovice nad Svitavou and Brno-Jundrov, the aphid damaged about 63% leaves. Larvae of fundatrices hatched from mid-April and their development from hatching to maturity took about 14 days. Mature fundatrices occurred in May and reproduced for a period of 14 days. Their average physiological fecundity amounted to 311 larvae and ecological fecundity 291 larvae. Migrantes alatae...
A statistical small-area method of estimation of spatial distribution of the tree damage degree
R. Podlaski
J. For. Sci., 2003, 49(8):380-388 | DOI: 10.17221/4711-JFS
The objectives of this study are to demonstrate a small-area method of estimation of the spatial distribution of the tree damage degree, and to initially verify it during the assessment of fir (Abies alba Mill.) and beech (Fagus sylvatica L.) vitality in the Świętokrzyski National Park. In order to estimate the degree of tree damage the classification based on the degree of defoliation, and assumed by the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests - ICP, was used. The tree damage degree is presented in P3 fields of the SINUS System of Information on Natural Environment....
Dieback of Austrian pine - the epidemic occurrence of Sphaeropsis sapinea in southern Moravia
L. Jankovský, D. Palovčíková
J. For. Sci., 2003, 49(8):389-394 | DOI: 10.17221/4712-JFS
In the course of recent years, various cases of Austrian pine dieback of all age classes have occurred in a number of localities. At all localities, Sphaeropsis shoot - killing of pine caused by Sphaeropsis sapinea (Fr.) Dyko et Sutton syn. Diplodia pinea (Desm.) Kickx. was recorded on a mass scale in declining shoots. Fruit bodies of the fungus were found on twigs, at the base of needles being particularly abundant on cones. Generally, the fungus is considered to be an opportunist pathogen which spreads on damaged tissues of shoots accelerating their dying. In trees with the same symptoms of damage, Brunchorstia pinea (Karsten)...