Is the introduction of covered root seedlings in every renewal reasonable – phytopathological point of view

Seedlings produced with a covered root system were intended to be used in the afforestation of ‘difficult’ soils in post−agricultural lands, on post−fire areas, in wastelands, within zones of industrial damage or on mining heaps. It is assumed that the suitable substrate and properly grown seedling ensure a good start for a plant in a new, unfavorable environment. In many forest districts so−called ‘container nurseries’ were established and produced millions of seedlings with a covered root system, including seedlings equipped with mycorrhiza under them, controlled mycorrhization. In recent years, however, more and more often such seedlings are also introduced into forest soils during the renewal of logging or gaps. Phytopathology sees many weaknesses of such an approach. The article indicates potential and actual threats in the production cycle of planting material in containers and after planting trees in cultures

Effect of fungi decomposing roots of forest trees on CO2 release - an attempt of evaluation

On the basis of literature data and own research, algorithms for the calculation of the amount of released CO2 and C per hectare per year were developed taking into consideration 1) the share of trees infected by root pathogens in 80−year−old pine stands, 2) the weight of tree roots, 3) the share of cellulose in the wood of roots and 4) the loss of cellulose degraded by fungi. The developed model after transformations contains only a) the merchantable timber volume of trees per hectare to be harvested based on measurements or SILP database and b) the area of occurrence of fungi causing wood decay in roots and stumps (here: Heterobasidion spp., Armillaria spp. and Phlebiopsis gigantea). These data can also provide estimates of the level of carbon sequestration in the non−infested forest stands