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On the basis of forest taxation data the presence of European ash in the Bardzkie Mountains area (central part of the Sudety Mountains) was analysed. This included the reckoning of the number of sites and the area covered by ash in various forest habitat types, age classes, altitude zones and on variously slanted and exposed mountain sides. The decline in the number of ashes in younger age classes and complete absence of trees older than 140 years have been noted. In the Bardzkie Mountains ash is the main species forming the forest on mountain riparian forest stands (a 43% participation in the area of forest of this type). Considering the number of specimens most ashes are scattered in mountain broadleaved forest. To the altitude of 650 m ash’ participation in the forest stand composition is stable (30% of analysed locations), but it occupies only 2.6% of total forest area.
The paper presents results acquired by an analysis of stand structure, regeneration processes and disturbance regime of a mixed natural forest located in the Carpathians (Central Slovakia). The data were collected on two permanent research plots located on different geological bedrocks (andesite and migmatites). Significant differences in the composition of the upper tree layer were observed among two types of geological bedrock. On the plot I (andesite), European ash (Fraxinus excelsior L.) occurred as a dominant component. An opposite situation was observed on the plot II (migmatites). The coexistence of beech (Fagus sylvatica L., spruce (Picea abies L. Karst.) and ash was recorded in the upper layer. The middle and lower layers were almost identical on both types of bedrock. The dominance of beech with the admixture of other tree species was observed. Regarding the structure of the present forest stand in relation to the structure of the gapmakers and natural regeneration, we observed a partial cyclical alternation of the tree species composition of this natural forest within the time span of several developmental cycles. The analysis of natural regeneration implied a crucial role of ungulates for the growth enforcement of ash individuals in the next generation of natural forest. Under the current condition, a negative trend in tree species diversity of the future generation of natural forest towards the dominance of beech was found.
Bacteria Pseudomonas aureofaciens, P. cepacia and P. fluorescens biovar I was tested againts fungus Diplodia mutila on stems of 2-year-old plants of European ash in greenhouse experiments. The interaction of bacteria and fungus was assessed on the base of length of necrotic lesions, caused by D. mutila, extended from point of inoculation. The strongest antagonistic effect was noted in the case of P. aureofaciens
The paper examines the influence of industrial emissions of sulphur (IV) and nitrogen (IV) oxides on the percentage of stem anatomical characteristics of the autochthonous woody plant species undergrowth of Acer platanoides L. and Fraxinus excelsior L. in the southern industrial zone of the city of Dnipro (Ukraine). It is ascertained, that the ratio of the primary cortex share to the central cylinder share does not change in the stems of annual shoots of the both studied woody plant species when they are exposed to the influence of the toxic gases. However, there are significant changes in the ratio of shares of histological elements in the undergrowth stems of F. excelsior. The use of both absolute and relevant values of anatomic parameters of the plant vegetative organs is needed to analyse the woody plants resistance to technogenic pollution of the environment.
During 2008-2009 the analytical studies were conducted on the species composition of galls occurring on the leaves of Fraxinus excelsior L. in localities: the Ojców National Park and the Przedborski Protected Landscape. A total of 3788 galls, including 1897 in 2008, were found. The galls represented 5 maker-species: Phyllocoptes epiphyllus (Nal.) (Acarina, Eriophyidae), Psyllopsis fraxini L., Prociphilus fraxini (Fabr.) (Homoptera, Psyllidae), Dasineura fraxinea (Kief.) and Dasineura fraxini (Bremi) (Diptera, Cecidomyiidae). The species composition of galls was similar in two localities. Psyllopsis fraxini was the most abundant species. The index of occurrence frequency and the Agrell's index of species co-occurrence have been calculated. It was shown that the strongest bond existed between Dasineura fraxinea and Psyllopsis fraxini in both localities.
W wyniku szczegółowych obserwacji stanu zachowania roślin drzewiastych (klonu pospolitego (Acer platanoides), klonu jaworu (Acer pseudoplatanus), jesionu wyniosłego (Fraxinus excelsior) oraz lip (Tilia cordata, T. x europaea) w pasach drogowych Krakowa stwierdzono masowe występowanie u większości badanych drzew podobnych objawów uszkodzeń, w postaci nekrotycznego zbrunatnienia blaszek liściowych, obejmującego 10-80% powierzchni blaszki oraz przedwczesnego opadania liści, niezależnie od rodzaju i gatunku. Ponadto obserwowano zamieranie pędów, zwłaszcza w środkowej części koron. Susz obejmował niejednokrotnie 80-90% konarów i gałęzi. Często w miejsce przedwcześnie opadłych liści rozwijały się nowe, jasnozielone, o zredukowanej powierzchni blaszki. Analiza fitopatologiczna i entomologiczna badanych próbek drzew wykluczyła działanie organizmów żywych. Wyniki pomiarów próbek gleb, pobranych spod chorych drzew, wykazały nadmierne jej zasolenie - od 0,5 do 0,8 mS·cm⁻¹. Stwierdzono również występowanie podwyższonego alkalicznego odczynu podłoża, przyjmującego wartość w zakresie pH 8-10. Biorąc pod uwagę całokształt wyników obserwacji sugeruje się, że masowe uszkodzenia drzew w pasach przydrożnych centrum Krakowa są spowodowane zniszczeniem gleby jako środowiska wzrostu korzeni drzew, w szczególności nadmiernym jej zasoleniem i alkalizacją.
The studies were carried out in the Włoszczowa Forest Unit, in 9 ash stands differing in respect of age, origin (natural, artificial), site and in the nursery on 3 quarters differing due to a silvicultural method (transplanted and not transplanted) and seedlings age. In each stand an analysis of disease symptoms was carried out on 100 trees (2 - 20 years old stands) or 50 trees (21 - 80 years old stands) growing side by side in central part of the stand, while in the nursery in each block 200 seedlings were analyzed (4 sectors with 50 seedlings each). From the infected seedlings and trees 120 fragments of dead branches, living branches with cankers, and dead roots were taken. Identification of fungi was made on the basis of fructification and over 300 isolations of fungi on malt agar medium. The most frequent disease symptoms in ash stands were: the dead top (34.7% trees), the dying of whole branches (83.5%), the dying of the top of branches (20.1%), the occurrence of healed (36.0%) and unhealed cankers (18.9%) and the slime flux (23.7%) on the trunk, also the chlorosis of leaves (7.5%) and their atrophy (11.2%). Most of the types of disease symptoms appeared irrespectively of the tree age, origin and site, sometimes showing only a difference in the frequency of occurrence. On the seedlings in the nursery the shoot discolouration, healed and unhealed cankers on shoots and necrosis of a part of leaves were recorded most frequently. Disease symptoms occurred more frequently on 4-year-old seedlings in comparison with 3-year-old. In respect of transplanted seedlings the leaves dying was more frequent. Within cankers and on dead tops of shoots the most frequent were: Alternaria alternata, Chalara sp., Cytospora ambiens, Diplodia mutila, Fusarium lateritium, Gloeosporidiella turgida, Phomopsis controversa and Phomopsis scobina. In sparsely found dead roots of living trees appeared mostly: Cryptosporiopsis radicicola, Cylindrocarpon destructans and Phialocephala sp.
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