RESUME

Natural forest regeneration in the Czech Republic
Jiří Šindelář (pp. 296-297)

The issue of increasing the natural regeneration in the forest management of the Czech Republic represents a subject of the whole forestry community’s interest at present. A forceful increase in the share of natural regeneration is namely envisaged by the Forest of the Czech Republic, state enterprise. Based on estimates and calculations by single tree species we can conclude the share of natural regeneration in the Czech forests may achieve some 3 200 ha annually during the several coming years, what represents about 10 % of the area to regenerate and afforest (including improvement). If we only considered the area of the first afforestation, except for non-forest land and improvement, the share of natural regeneration would make some 18 %. With the natural regeneration increasing gradually the need for plants and seed material will decrease proportionally. This represents an annual saving of some 18 millions of plants, i.e. about 9 % of total number of plants used for average every-year regeneration, afforestation, and improvement.

Inventory of service tree in Moravian Carpathian Mts.
Marie Benedíková, Zdeněk Prudič (304-305)

The authors scrutinised and mapped the occurrence of service tree (Sorbus domestica) during four years until 1999. They measured 152 service trees in forest stands and 111 trees out of forest in total. In the Czech forests the species grows to the height of 26 m, with the stem length of even 15 m and d.b.h. of 66 cm, it forms a well-shaped tree in the canopy closure. The height of free-growing trees ranges around 15 m; the oldest specimen has 144 cm d.b.h. In order to conserve the species’ gene pool in the Southern Moravia trees favourable to further propagation were selected (74 pieces so far) which were inoculated or grafted onto service tree seedlings. The plants originated in this way will establish a seed orchard in 2000. In 1997 seed material from 50 trees was collected which produced roughly 15 thousand seedlings. Part of them has already been planted into forest stands, others into bio-corridors. More than 3 000 service trees were returned back to the landscape in 1999.

Bark necrosis in beech
Vlastislav Jančařík (pp. 314-316)

In the beginning, the author mentions the bark necroses of forest tree species do not rank among studied and observed fungi diseases and neither beech necroses were paid the proper attention. The most frequent bark necrosis pathogens in beech stands are represented by Nectria galligena Bres., N. dittissima Tul., and N. coccinea Fr. N. coccinea is usually related with damage of beech bark caused by sucking by coccus Cryptococcus fagisuga Lind. These fungi cause so called open bark necroses with repeated healing related to action of the fungi’s metabolites and their impact on refreshed healing and repeated opening of necrotic wounds. The protection is based on the negative health selection of injured and heavily infested trees, which are not expected to ensure quality production of timber. These trees have to be deleted during all silvicultural and tending interventions winthin the framework of routine and well-known principles of forest health and hygiene. Only then we can expect the bark necroses not to become a more significant economic and forest protection issue.