Warsaw, Poland
Warsaw, Poland

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Zybura H.,Katedra Hodowli Lasu | Pewniak B.,Nadlesnictwo Zloczew
Sylwan | Year: 2016

Currently observed climate change creates favourable conditions for the development of not only deciduous species (oak and beech), but also some coniferous (e.g. fir). In the Scots pine stands growing on fertile forest site types one can observe the dynamic development of the under- -canopy layers composed of those species. Oak or beech saplings are often characterized by good silvicultural value. Also silver fir creates a well-developed cover under Scots pine trees. Beech and fir as the most shade-Tolerant tree species are able to handle the conditions under Scots pine. They can grow for a long time under the cover without damage to their height or diameter growth. Especially, a dynamic growth of oaks can often be observed on fresh mixed coniferous and fresh mixed broadleaved habitats. Oak layers in Scots pine stands are generally created in the way of natural regeneration with remarkable contribution of the jays, which spread the seeds even at considerable distances from the old trees. The corresponding intensity of thinnings supports to shape the proper silvicultural value of such under-canopy storeys. Observations on growth of such stand layers in the Scots pine stands in eastern and central Poland consider the desirability of including them in the next generation of stands. Their presence contributes to improvement of the biological stability of the stands, and also leads to increased productivity. By implementing to the forest practice the model of semi-natural silviculture, one wants to consider the possibility of using the saplings currently existing under the Scots pine as a component of the future stand. Knowledge about the silvicultural value and the impact on growth of lower layers will enable to develop the principles of proper cultivation of the multi-storey stands.

Study presents a classification model for predicting the occurrence of mass damage in young forest plantations caused by insect pests on roots belonging to Melolontha genus. Logistic regression model was built on the basis of 10 taxation features describing 177 young stands. Habitat fertility, occurrence of Scots pine and European beech, and weed infestation of the habitat are the most significant features that influence mass occurrence of cockchafer larvae acting as insect pests on roots in plantations.

The effect of the controlled mycorrhization with the fungus Hebeloma crustuliniforme, the application of fungicides (Bayleton 25 WP, Falcon 450 EC, Nimrod 250 EC and Siarkol Extra 80 WP) in the nursery and the use of two types of substrate (a mixture of sterilized Estonian peat with vermiculite and unsterilized Polish peat with perlite) on the growth, level of infestation by powdery mildew and form (single, multi-stem) of oak trees in the first four years after planting was analysed. The type of the substrate and controlled mycorrhization did not affect the growth of young trees. Oaks treated with Nimrod in the nursery were the tallest after outplanting, but grew slower compared to trees in other variants. The oaks protected with the triazole fungicides (Falcon and Bayleton) in the nursery showed higher level of infestation by powdery mildew in the plantation.

Different methods of logging slash management (LSM) and methods of soil preparation (MSP) can create different conditions for the growth of forest trees. This occurs through variation in soil aeration, tree nutrition or microbial conditions. These factors are modified by climate, soil fertility, treats from insects or fungal pathogens and renewed species. The aim of this study was to compare effects of three LSM methods: 1) crushing and mixing with the soil by Mery Crusher, 2) chopping and leaving on the soil surface, and 3) removal from the clear-cut, and three MSP: 1) double-mouldboard forest plough LPz-75, 2) active plough U-162, and 3) forest mill FAO-FAR FV 4088 on biometric parameters, density and survival of six-years old Scots pine seedlings. Field research was conducted in Narol Forest District (south-eastern Poland). The soil in the study area was classified as brown podzolic, formed on loose sands with typical mor humus. The experiment was established by planting 10 000 one-year-old pine seedlings per hectare, after clear cut and followed by a two-factor block design consisting of nine variants distinguished on the basis of LSM and MSP randomly assigned to each of the three blocks. Tree height and root collar diameter were measured three times, at the end of 1st, 3rd and 6th growing season. The results showed no statistically significant differences in the size of the analyzed parameters of planted seedlings. Seedlings in the variant with site preparation by crusher and forest mill were slightly higher and thicker. This indicates the better trophic conditions in that variant. LSM did not affect either seedlings density or their survival. A slightly higher survival rate and tree density occurred in variants with crusher regardless of soil preparation method. It follows that, all presented experimental variants give similar results. Therefore, selection of the most appropriate methods of site and soil preparation should primarily respect ecological and economic indicators, and such local factors as microclimate, mainly precipitation, site fertility and threats from pests and fungal diseases.

Brzeziecki B.,Katedra Hodowli Lasu | Drozdowski S.,Katedra Hodowli Lasu | Bielak K.,Katedra Hodowli Lasu | Buraczyk W.,Katedra Hodowli Lasu | Gawron L.,Katedra Hodowli Lasu
Sylwan | Year: 2013

The paper presents preliminary results and experiences concerning promoting diverse structures in forest stands dominated by light demanding tree species, i.c. those that prevail under conditions of Polish lowlands. Data was collected in the 'Control Unit Browsk 28C, established in 2002 in the managed part of the Białowieża Forest (eastern Poland) and surveyed again in 2011.

Paper compares various analysis methods suitable for an analysis of point pattern with directionally varying point density. As example was used point pattern from spacing experiment created according to Nclder design in which tree density changes greatly but in smooth manner. Such a pattern could be not analysed by methods assuming homogenous point density e.g. classical estimator of Ripley's K function. More useful are estimators of Ripley's and pair-correlation functions for inhomogeneous point patterns. KZ function, which proved to be efficient for heterogeneous point patterns with distinct changes in the local point density appears not to be efficient for heterogeneous point patterns with smooth changes in density.

Brach M.,Katedra Urzadzania Lasu | Bielak K.,Katedra Hodowli Lasu | Drozdowski S.,Katedra Hodowli Lasu
Sylwan | Year: 2013

Paper presents results of measurement accuracy evaluation of two laser rangefmders (TruPulse and ForestPro integrated with MapStar compass) mounted on monopod and tripod under the forest conditions. The precise data on spatial coordinates of 34 trees in the Rogów Arboretum and 8 points from the geodetic control network in the Głuchów Forest were used. The results show that the measurement sets equipped with ForestPro and MapStar were more accurate than TruPulse ones. However, no significant influence of applied stands on the measurement accuracy was observed.

The study presents spatial variation in the height of a 12-year-old oak regeneration in the north-south and east-west gradients in the cut patches with a similar width (28 m) but differing in length (33-70 m), with the longer side facing east-west direction. A comparison of the cut patches with an area of 7,11 and 16 ares showed that oaks in large patches were on average 25% higher than in small patches and the diversity of trees in the WE and NS gradients depended on the size of the patch. In each case, the lowest trees occurred in the zone of strong root competition of shclterwood, whose influence decreased with the enlargement of the cut patches. The results of the study show that the establishment of large (15-20 ares) elliptical or rectangular patches whose area can be expanded by lengthening the axis in the east-west direction is the recommended method of pedunculate oak renewal in forest practice.

Zajaczkowski J.,Katedra Hodowli Lasu | Brzeziecki B.,Katedra Hodowli Lasu | Perzanowski K.,Issyk-Kul State University | Kozak I.,Issyk-Kul State University
Sylwan | Year: 2013

An influence of environmental changes upon forest tree species competition was studied for suggested scenario of environmental changes (3-4°C increase of monthly temperatures), 8 main tree species and 6 natural regions. For a synthetic assessment of the reaction of various species for thermal and higric parameters of the climate, the growth multipliers DDGF and SMGF were used. The main environmental factor influencing future growth of tree species in Poland will be water shortage due to increased evapotranspiration. Regional decrease of water sensitive species importance, eg. alder, spruce and birch, accompanied by country-scale expansion of highly competitive, late-successional species, eg. beech and hornbeam is expected.

We investigated annual height increment of sessile oak and common hornbeam planted on clear-cut in respect to the distance to the adjacent mature Scots pine stand. The study area was divided into 3 zones (I-III) each of 20 m width. The four analyzed treatments were defined on a basis of a mingling form: W1 - a monoculture of oak (control plot), W2 and W3 - two types of row mixture, W4 - single tree mixture. Two years after planting an annual height increment of both tree species was significantly higher in the zone I (adjacent to the mature pine stand from the SW side) than in two other zones. The same significant differences were also found at the other inventories. Although hornbeam was on average higher than oak, a growth inhibition of oak by hornbeam was not significant. The annual height increment of both species was correlated with the precipitation in June and July. © 2014, Polish Forest Society. All rights reserved.

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