scholarly journals Occurrence of disease symptoms and selected biotic factors connected with beech (Fagus sylvatica L.) dieback phenomenon in stands of The Magurski National Park

2012 ◽  
Vol 58 (2) ◽  
pp. 441-452
Author(s):  
Piotr Rojek

The studies were carried out in 12 beech stands, growing on mountain fresh forest site in Magurski National Park. Stands differed in respect of exposition (northern and southern) and age - lower age classes (21-60 years old) and higher age classes (81-120 years old). This paper presents evaluation of frequency of disease symptoms occurrence in the crowns and on the trunks of beeches. The presence and the place of occurrence of fungus <i>Ascodichaena rugosa</i> and insects <i>Cryptococcus fagisuga</i> and <i>Ectoedemia liebwerdella</i>, which could be connected with beech bark necrosis on the trunks were noted down. In each stand 50 trees, growing side by side in center of the stand, were analyzed. Among 600 analyzed trees of <i>Fagus sylvatica</i>, 2.6% had a dead top. Crown thinning were present on 51.8% of trees. It appeared frequently in higher age class stands and didn't cover more than ¼ of the crown. Moreover, in crowns of 4.1% of trees the leaf chlorosis appeared. The most frequent symptom on trunks of beeches were local necroses (98% of trees), that were sometimes connected with slime fluxing (3.3%). Necroses were the most number in stands growing on the southern exposition and on south parts of the trunks. <i>Cryptococcus fagisuga</i> appeared mostly in high age class stands. Intensity of its appearance was similar on the trees growing on the southern and northern exposition (respectively, 48.3% and 53.3%). Particular parts of the trunks were colonized with similar frequency by <i>C. fagisuga</i> irrespective of cardinal points (N-29.3%; S-21.7%; W-22.7%; E-26.2%) and number of necroses on the trunks. <i>Ascodichaena rugosa</i> appeared on 8.6% of trees, more frequently on their north parts of the trunks (7.3%). In the places colonized by fungi <i>A. rugosa</i>, insect <i>C. fagisuga</i> was absent. Occurrence of larvae of <i>Ectoedemia liebwerdella</i> was mostly found on trunks of beeches growing on the southern exposition (43.0%), on 35.3% of trees they colonized south parts of trunks. There wasn't observed any connection between the occurrence of these larvae and symptoms of local necroses.

2015 ◽  
Vol 3 (3) ◽  
pp. 85 ◽  
Author(s):  
Erna Maya Sari ◽  
Sugeng P. Harianto

Repong Damar in Pahmungan, West Coastal District is a buffer of Bukit Barisan Selatan National Park (TNBBS).  Repong Damar is one example of the success of agroforestry systems managed by local community that is still very traditional.  This area was identified as a component of siamang (Hylobates syndactylus) habitat.  The absence of data and the latest information about the siamang groups in Pekon Pahmungan were reasons of this research.  The purpose of this research was to determine the siamang groups in Repong Damar, used concentrated area methode.  The research was done on April 2015.  The results showed that the existence of siamang group in Repong Damar Pahmungan were 4 individuals/group.  The distribution of age classes in the individual phases of adult siamang were 2 individuals and the individual of adolescent phase were 2 individuals.  The sex ratio in the adult age class phase was 1:1 and at adolescent age class phase was 1:1.  Keywords: siamang, groups, repong damar


2012 ◽  
Vol 60 (1) ◽  
pp. 123-133
Author(s):  
Tadeusz Kowalski ◽  
Paulina Materniak

Field studies were conducted in the years 2003 - 2005 in the Rymanów Forest Unit in 13 stands aged between 40 to 100 years, which had 10% - 60% of the sycamore in their species composition. They grew on a mountain forest site (12 stands) and mountain riparian forest (1 stand). In each of them 100 trees were examined, growing next to each other in the central part of the stands. The disease symptoms, on trunks and in the crown area of each tree, and their intensity were determined according to the predefined symptomatic - developmental code. More than 80 fragments of wood and bark were collected from trunks of living and dead trees with local cankers and bark peeling off exposing wood. From the samples, 798 isolations were made on 2% malt - agar medium. The examined sycamores in the Rymanów Forest Unit showed a large variation in the disease symptoms and their occurrence frequency. Among 1300 analyzed trees, only 13.7% did not show external, macroscopic disease symptoms. There was a relatively large share of dead trees (15.0%), which in individual stands ranged 4.0 - 32.0%. The most frequent symptoms in crowns were as follows: top dying (6.3% trees), entire branch dying (16.2%) or only their tops (9.6%), crown thinning (19.4%), leaf atrophy (10.8%) and leaf discoloration (11.6%). On sycamores trunks, the following symptoms were found: plate-like and strip-like necrosis of bark that was breaking, falling off and exposing wood (8.6% trees), local bark cankers (14.7%), among which healed ones dominated (10.3%), bark cracks (14.3%) and tree cancer symptoms (3.8%). Bark necrosis and wood exposure formed 1.5 times more frequently on the northern and western side than on the southern and eastern side, bark cracks appeared most frequently on the southern trunk side. On the cross sections of sycamore trunks, the following symptoms were found predominantly: T-shaped discolorations which appeared in the place of local healed cankers, dead wood regions in the places of local unhealed cankers and widespread bark cankers, sometimes taking the form of a sector reaching the part near the pith, and greyish - green or greenish - brown wood discolorations in the form of numerous stains, especially in the trunk periphery part. On the trunks of 184 (14.2%) sycamores, perithecia of <i>Nectria coccinea</i> were present. They formed in the area of cankers on bark and exposed wood alike. Fruiting bodies of <i>Nectria cinnabarina</i>, <i>Eutypa acharii</i>, <i>Melanomma pulvis-pyrius</i>, conidiomata of <i>Cytospora ambiens</i>, <i>Aposphaeria</i> cf. <i>pulviscula</i> and conidiomata of <i>Stegonsporium pyriforme</i> occurred sporadically. From wood, the following were isolated predominantly: <i>Basidiomycetes</i> sp. 1, <i>Chalara</i> sp. 1, <i>Cadophora fastigiata</i>, <i>Nectria cinnabarina</i> and <i>Cytospora ambiens</i>. <i>Chalara</i> sp.1, with its morphological features, best matched the anamorph of <i>Ceratocystis coerulescens sensu lato</i>.


2018 ◽  
Vol 79 (2) ◽  
pp. 113-117
Author(s):  
Szymon Bijak ◽  
Katarzyna Orzoł

Abstract This paper investigates the slenderness of black locust (Robinia pseudoacacia) trees in relation to the biosocial status of the trees, stand age class, crown parameters and habitat type. The research material was collected on 35 research plots in the Sława Śląska, Sulechów and Głogów forest districts in western Poland and comprises 1058 trees. For each tree, we measured height (h) as well as diameter at breast height (d) and determined its biosocial status (Kraft class), crown length (CL) and relative crown length (rCL). The age class and habitat type were assessed at the plot level. Because the obtained values for slenderness (s=h/d) diverged significantly from the normal distribution, we used Kruskal-Wallis and Mann-Whitney tests to investigate the influence of the above-mentioned parameters on the h/d ratio. Black locust slenderness ranged from 0.31 to 1.95 with an average of 0.91 (standard deviation 0.24). It furthermore differed significantly between Kraft classes (the higher the biosocial status, the lower the slenderness) and age classes (the older the trees, the lower their slenderness). We also found a significant effect of the habitat type (in oligotrophic sites trees formed more slender trunks than in mesotrophic sites) and crown parameters on the h/d ratio (decreasing with increasing crown length and relative crown length). The obtained results suggest that the slenderness of black locust does not differ substantially from native broadleaved trees in Poland.


2019 ◽  
Vol 80 (1) ◽  
pp. 13-21 ◽  
Author(s):  
Jan Bodziarczyk ◽  
Jerzy Szwagrzyk ◽  
Tomasz Zwijacz-Kozica ◽  
Antoni Zięba ◽  
Janusz Szewczyk ◽  
...  

Abstract The composition and structure of forest stands in the Tatra National Park were examined using data gathered in 2016 and 2017 from 617 circular sample plots (0.05 ha each). The diameter at breast height of all living trees, standing dead trees, snags, and wind throws was measured along with diameters and lengths of fallen logs within the plot boundaries. Tree height was measured for all living trees within the core (0.01 ha) of the sample plots. Using the obtained data, height-diameter curves were calculated for all major tree species and in the case of spruce, the height-diameter relationships were also calculated separately for each of the three elevation zones (up to 1200 m, between 1200 and 1400 m, above 1400 m). For each elevation zone and park protection zone, we also determined the volumes of live and dead trees. The volume of living trees in the Tatra National Park amounted to 259 m3/ha, which was higher than the volume of dead trees (176 m3/ha). Snags constituted the largest part of the dead wood whilst over 97% of the standing dead trees were spruce Picea abies. Among living trees, the share of spruce ranged from 81% in the low elevation zone to 98% in the middle zone. Other significant species in the lower zone were Abies alba (11%) and Fagus sylvatica (4.5%), while in the middle and upper elevation zones only Sorbus aucuparia occurred in significant numbers. Furthermore, in the lower elevation zone, Fagus sylvatica was the only species displaying significantly higher volumes in the ‘strict protection’ zone compared to the other park areas. In the ‘landscape protection’ zone, Picea abies was the most dominant species and the share of other species in the lowest elevation zones calculated based on tree density was smaller than calculated based on tree volume, indicating problems with stand conversion from spruce monoculture to mixed forest.


2010 ◽  
Vol 56 (No. 1) ◽  
pp. 18-27 ◽  
Author(s):  
M. Nawrot ◽  
M. Jakubowski ◽  
W. Pazdrowski ◽  
K. Kaźmierczak ◽  
M. Szymański

The paper presents an attempt to determine conducting area (CA), relative conducting area (CA.k<sup>–1</sup>) and mean ring conducting area (CAar) on discs cut at breast height from stems of larch trees growing in fresh mixed coniferous forest and fresh mixed forest sites, representing four age classes and the main crop according to Kraft’s classification. The value of CA increases with an improvement of the social class of tree position in the community, while no such dependences were found for the value of (CA.k<sup>–1</sup>). The parameter CAar, except for one case in age class IV in the fresh mixed coniferous forest site, increases with an improvement of the position a tree takes in the community and differentiates more markedly under the conditions of fresh mixed forest sites. Relative conducting area (CA.k<sup>–1</sup>) decreases markedly with an increase in the age of trees, which is confirmed by high values of the coefficient of determination. Moreover, the significance of differences between individual trees in the main crop according to Kraft and forest site types was tested in terms of the values of CAar. Calculated values may be used to describe the relationships between conducting area and the size of the assimilating organ more precisely than the total sapwood zone.


2004 ◽  
Vol 34 (6) ◽  
pp. 1296-1310 ◽  
Author(s):  
Olli Tahvonen

This study combines timber production and environmental values, applying a dynamic forest-level economic model with any number of forest age-classes. The model includes endogenous timber price or nonlinear harvesting costs and various possibilities to specify the dependence of environmental values (related e.g. to species persistence) on the forest age-class structure. The nonlinearities in the net benefits from timber production have the consequence that fluctuations in optimal timber harvesting may totally vanish or at least become smaller than in forest scheduling models without ad hoc even flow constraints. If environmental values are specified to depend on the fraction of forest land preserved as old growth, the optimal long run allocation between timber production and old growth is represented by an equilibrium continuum. Thus the optimal long run allocation depends on the initial age-class distribution. The continuum and the dependence of initial age-class distribution vanish when the rate of discount approaches zero. If the environmental values of age-classes increase smoothly with age, the long run equilibrium may simultaneously include multiple rotation periods. The model determines the optimality of producing timber and environmental values separately at different parts of the forest or at the same piece of forest land. Numerical computation suggests that the optimal solution always converges toward some optimal long run stationary age-class distribution.


1915 ◽  
Vol 22 (6) ◽  
pp. 713-731 ◽  
Author(s):  
A. E. C. Lathrop ◽  
Leo Loeb

1. In crossing strains known to diner in their tumor rates, the hybrids show in a considerable number of cases a tumor rate corresponding to the parent with a high tumor incidence; in some cases the offspring have the tumor rate of the parent with the low tumor incidence; in certain cases the tumor rate of the offspring is intermediate between those of the parents. That these results are not accidental follows from the fact that we could show in some cases that two sisters crossed with the same strains or with the same male give similar offspring, and in other cases we could show that the same individual crossed successively with two strains that behave similarly produces hybrids with a similar tumor incidence. 2. There exists some evidence for the conclusion that different strains in being crossed with other strains differ in their power to impress their tumor rate upon the crosses. Thus the English strain and the I and II daughters of No. 10 have the tendency to transmit to the offspring a high tumor rate, while Cream, Silver, and some European other than 151 have a tendency to transmit a low tumor rate. While crosses of these daughters of No. 10 with European 151 or with No. 8½ show the high tumor rate of the mothers, the crosses of one of the same females with Cream or Silver show an intermediate tumor rate. 3. We find further evidence for our conclusion previously stated that age class, of the tumors and tumor rate are not dependent on the same factor. The age class enters into the crosses as a factor independent of the tumor rate. Thus we find in the crosses between the first daughter of No. 10 and Cream, and in the crosses between the same female and English Silver a similar tumor rate, but the age classes differ in conformity with the difference in the age classes of the parents. We find, furthermore, that while in some cases a tumor rate and an age class that correspond to each other (high tumor rate, early tumors—low tumor rate, late tumors) are transmitted to the offspring, in other cases tumor rate and age class transmitted to the crosses diverge. 4. It seems that certain strains with very late tumors if mated with strains with earlier tumors have a tendency to transmit to the offspring their own tendency to very late tumors. With a certain strain lateness of the tumors seems to be dominant, while a low tumor rate is not necessarily dominant in the same crosses. This was noticeable in the crosses into which the strain European ± 102 or 103 entered as one of the parents. 5. If both parents have a similar tumor rate the offspring have usually a similar tumor rate. There was, however, one exception to this rule in the case of the German ± Carter mice, in which the offspring showed a much lower tumor rate and higher age class than either of the parent strains.


1987 ◽  
Vol 65 (1) ◽  
pp. 107-111 ◽  
Author(s):  
Candace Galen ◽  
R. C. Plowright

Stigma peroxidase activity was tested in flowers of Pedicularis canadensis and Clintonia borealis at discrete age-classes during the course of anthesis. For recipient flowers of each age-class pollen adhesion, rate of pollen germination, and total number of grains germinating on stigmas were scored following hand-pollination. In P. canadensis, the onset of detectable peroxidase activity occurred at the transition from the juvenile to pollen-dehiscing age-class. Concurrently, the stickiness of the stigma surface and total number of grains germinating on the stigma increased significantly. Stigma peroxidase was present to some degree throughout anthesis in C. borealis. However, the percentage of the stigma surface in which peroxidase was detectable increased significantly between straight-sided and medium-curled flower age-classes. Again, corresponding increases occurred in the stickiness of the stigma surface and total number of grains germinating. Results suggest that for both species stigma peroxidase activity is a reliable indicator of receptivity.


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