|Forests and forestry in 2021|
We explained the mission of this column in a double issue of Forestry Journal several years ago. We pointed out that the intention of the column was not to teach forestry experts about forestry (the profession which they study at the faculty), but to point to some current events taking place in the forest and the forestry profession. By stating the facts, we try to help the forestry practice and science to take a stand on a particular professional problem or event, all with the view of protecting the forest and the profession. Therefore, let us remind ourselves of last year’s columns, which point to the problems that await us in the future.
In the double issue 1-2/2021 we announced the year-round celebration of the 175th anniversary of the founding of the Croatian Forestry Society (1846) and the 145th anniversary (1877) of the publication of the scientific-professional paper Forestry Journal. Among other things, we pointed out that the Croatian Forestry Society achieved its two main goals. The first was the introduction of higher forestry education in Croatia by founding the College of Agriculture and Forestry in Križevci in 1860 and the Academy of Forestry (the present Faculty of Forestry) in 1898 as the fourth higher education institution of the University of Zagreb. The second goal was achieved by publishing the first issue of Forestry Journal on January 1st, 1877. We especially emphasised that the awareness of the need for higher education to manage forest ecosystems was keenly felt even then. We asked ourselves what the current situation was regarding the forestry profession. We concluded it was dire: everybody knows everything about the forest without having the slightest idea of the forestry profession. We also drew attention to the non-market management of forest resources, particularly the most valuable ones, when by exporting wood raw material instead of wood processing products, we export jobs and devalue the long-lasting hard work of forestry experts.
In the double issue 3-4/2021, we discussed the text by Thomas Waitz, representative of the Green Party in the EU, published under the bombastic title “New Report on Deforestation in Croatia”, which our Greens immediately “embraced”. In view of over 250 years of managing our forests according to the principle of sustainable management, this title is an insult to Croatian experts. In addition, this mixing up of the concepts of deforestation and controlled felling of forests is a blatant example of ignorance, or rather amateurism, which today permeates not only forestry but also other professions. We warmly recommend rereading this Editorial in order to gain a stronger basis for a possible debate of this subject.
The Editorial in the double issue 5-6/2021, was entitled “The demise of a man who has devoted his life to forests and forestry”. Although his life path was extensively presented in the column “In memoriam”, we briefly described the most important points of his life path, concluding: “The demise of Professor Matić ends a period which we, his contemporaries, will always look upon as an unforgettable experience of living a noble foresters’ life in togetherness, the result of which are well-tended and preserved forests. Will the new trends, increasingly visible in present day forestry, in which foresters have less and less contact with forests and with their colleagues, be able to respond to all the challenges, particularly in the light of distinct climate changes, remains to be seen.”
The topic of the double issue 7-8/2021 “Who is to blame for poor business results of wood processors?” is accompanied by the text of the European Forestry Institute and the World Bank, entitled “A survey and recommendations for the wood raw material sale system in the company Croatian Forests Ltd.” According to the text, 93 % of wood products in Croatia are sold administratively on the basis of long-term contracts, and only 5 % are sold on the market (Poland 89 - 90 %, Czechia 96 %, and Estonia and France about 100 % on the market). Compared to European prices and prices in neighbouring countries, Croatia sells wood raw material at prices which are 30 – 30 % lower, which incurs a loss of about 316 million kuna annually (oak 163 million kuna, beech 105 million kuna, spruce and fir 48 million kuna). Taking into consideration the principles of sustainable management, as well as the quality and naturalness of Croatian forests (which has earned them the FSC certificate – of which it is the wood processors who reap the highest benefits), we suspect that the losses are even higher than the ones mentioned above.
The topic of the double issue 9-10/2021 was “What does the new EU forest strategy for 2030 bring?” A core part of the European Green Deal, this strategy anticipates a reduction of greenhouse gas emissions by at least 55 % by 2030 and a climate-neutral continent by 2050. It also helps meet EU targets to increase CO2 removal through natural sinks under the Climate Act. The strategy gives forests, foresters and the forest-based sector a central role in meeting these targets. With their help, a European transition to a modern, climate-neutral, resource-efficient and competitive economy is expected.
The double issue 11-12/2021 was concerned with predictions contained in the text “What does the Glasgow Conference bring us?” As part of the signed Declaration on Forests and Land Use, which has so far been supported by over 140 countries in which more than 90 % of world’s forests are located, the leaders pledged to work together to “halt and reverse forest loss and land degradation” by 2030. The main objective of the conference was to limit the increase in global average temperature to a level significantly lower than 2 °C above the level in the pre-industrial period. Here, we are concerned about the fact that those who are uninformed, but in position of authority, equate deforestation and controlled felling, which is a silvicultural operation performed in order to maintain and regenerate forest stands. Despite the fact that Croatia is highly forested, this could significantly affect our proven success in the management of our forests.
|ORIGINAL SCIENTIFIC PAPERS|
|Mario Božić, Marijana Andabaka, Mislav Vedriš, Ernest Goršić, Krunoslav Teslak|| UDK 630* 923 + 924 (001)
|Characteristics of private forest owners in relation to their activities in enlargement of forest holdings|
Most forest owners in Croatia have forest holdings smaller than 1 ha, while less than 1% have holdings larger than 10 ha. Parcelization of forest holdings in addition to small size presents significant limitation for forest management. Therefore, important aim of forest policy is to stimulate enlargement and consolidation of forest holdings. First step in that process is to recognize the characteristics of forest owners interested in enlargement of their holdings and active forest management.
The aim of this research is to relate the sociodemographic attributes of private forest owners and characteristics of their forest holdings with their interest for selling and/or buying forest estates for enlargement and consolidation of forestland area.
Direct survey questionnaire covered 500 private forest owners in continental part of Croatia. Respondents are classified by sex, education, employment, location of forest holding, activities in forest associations and means of acquisition of forest estate. Answers included level of interest for activities in enlargement and management of forest holdings. Statistical analysis included descriptive statistics (arithmetic mean, median, and standard error), testing between groups (Mann Whitney and Kruskal Wallis test), and Spearman rank correlation.
The results indicate correlation of sociodemographic, regional and other characteristics of forest owners with their interest in enlargement of forest holding. According to these results most interested in enlargement of forest holding are younger male owners from the central Croatia who purchased forest and are already active in forest associations (tables 1 and 2). Non-employed and self-employed owners are also more interested in enlargement of forest area to increase their incomes (table 1). However significant share of owners (35%) are not interested in increase nor in selling their forest (Figure 1) which is an impediment in consolidation of forest areas.
The results of this study are useful for future forest policies aimed at small scale forestry, although these actions are subject to large scale restrictions due to increase of protected areas and limitations to forest management resulting from reducing carbon emissions. Therefore, state regulatory measures should aim at subsidizing active and diversified forest management (forest biomass, non-wood forest products, amenity values, credits for carbon sequestration, aimed species, biodiversity). On the other hand, law measures should improve the process of inheritance and penalize the abandonment of forest areas (sources of pests and diseases, invasive species, forest fires).
Key words: private forests; purchase and selling of forest area; forest management; consolidation
BOŽIĆ, Mario ŠL
VEDRIŠ, Mislav ŠL
GORŠIĆ, Ernest ŠL
TESLAK, Krunoslav ŠL
|Vinko Paulić, Tomislav Škarica, Damir Drvodelić, Milan Oršanić|| UDK 630* 270 (001)
|Acoustic tomography assessment of decay in sessile oak trees|
Urban trees and forests contribute to citizens’ wellbeing and provide a wide range of benefits. Yet in the urban environment, trees are exposed to a range of abiotic and biotic factors that can impair growth. Wood decay fungi are a major cause of tree failure. Devices supported methods that measure certain wood properties are often used in addition to visual assessment of urban trees. Acoustic tomography is a device that measures the velocity of sound wave propagation through wood in the radial and tangential directions and is used to assess internal defects in trees. The aims of this study were to determine the size and position of healthy and decayed wood and to define the accuracy of acoustic tomography on ten old sessile oak trees in the Maksimir Forest Park, Zagreb. Results of acoustic tomography images (tomograms) were compared with photographs of tree cross sections after felling to confirm decay. The visual assessment indicated the presence of decay on ten trees, and this decay was visible on eight of ten tomograms. Decay was further confirmed in seven cross-sections after felling. Of these, three trees had incipient wood decay, while four had active wood decay with cavity formations. The shape of tomograms and position of decay were similar to the cross-section photographs for eight and nine trees, respectively. The area of decayed wood in different wood condition categories was correctly shown on the tomograms in comparison with the cross-section photographs in six of the trees. Acoustic tomography underestimated the area of sound wood and overestimated incipient wood decay in comparison with the actual state of cross-sections, while the area of active degraded wood and cavities was accurately represented.
Key words: sessile oak; urban forest; arboriculture; acoustic tomography; decayed wood
DRVODELIĆ, Damir ŠL
ORŠANIĆ, Milan ŠL
|Željko Zečić, Andreja Đuka, Dinko Vusić, Branko Ursić, Davor Benić|| UDK 630* 811 (001)
|The structure of above-ground biomass of wild cherry (Prunus avium L.) in lowland Croatian forests|
The paper presents the structure of the total above-ground biomass of wild cherry (Prunus avium L.) trees in the area of the Spačva basin in the Vinkovci Forest Administration. The research was performed on 120 samples of wild cherry trees with a diameter at breast height (DBH) ranging from 10 to 72 cm and tree height ranging from 10.8 to 34.4 m. Timber assortments were processed according to the Croatian Standards for Forest Exploitation Products from 1995.
The assortment structure of sample wild cherry trees shows significant deviations in relation to the assortment structure tables used by the company ”Croatian Forests” Ltd. Zagreb. The share of veneer logs ranges from 9.29% (37.5 cm) to a maximum of 19.50% in the diameter class of 67.5 cm. Sawmill logs of the first quality class range from 12.04% (72.5 cm) to 19.89% (32.5 cm), and of the second quality class from 17.30% (62.5 cm) to 26, 89% (32.5 cm). Thin roundwood assortment is represented in the diameter class of 17.5 cm with 17.44% and immediately in the next with 15.90%, while in the higher diameter classes it is significantly less represented. The share of stacked wood (firewood and pulpwood) is the highest in the first diameter class, 88.76% (12.5 cm) and in the next two with 67.44% and 47.71%, and is the lowest in the diameter class 67.5 cm with share of 27.01%. The average share of stacked wood is 42.09%. Waste in the total structure ranges from 11.24 (12.5 cm) to 19.12% (27.5 cm), and is on average 16.47%. Double bark thickness ranges from 0.53 cm to 3.37 cm, with an average of 1.66 ± 0.57 cm, and the percentage of bark share ranges from 4.77% to 16.46%, with a mean value of 9.02 ± 2.01%.
The parameters of the Schumacher-Hall equation, wood density, moisture content, branch volume (diameter <7 cm) and the structure of total aboveground biomass were also determined.
Key words: wood volume; wood assortments; bark thickness; wood waste
ZEČIĆ, Željko ŠL
VUSIĆ, Dinko ŠL
|Dalibor Ballian, Mirzeta Memišević Hodžić|| UDK 630* 232.1 (001)
|Variability of pedunculate oak (Quercus robur L.) in Bosnian-Herzegovinian provenance test: correlations between growth and leaf morphological traits|
Pedunculate oak (Quercus robur L., Fagaceae) is an economically and ecologically valuable species that has almost completely disappeared from the territory of Bosnia and Herzegovina due to over-exploitation, and through reintroduction and breeding activities it should be returned and protected in areas optimal for its growth. This study aimed to determine whether there is a correlation between the
morphological traits of pedunculate oak leaves in populations where the seed for establishing provenance test was collected with the root collar diameter and height of plants growing in the provenance test.
In the first part of this study, leaves from 27 natural populations of pedunculate oak throughout Bosnia and Herzegovina were measured (Table 1). Ten leaves per tree were measured from ten trees per population. The following traits were measured (Figure 1): K1 - leaf blade length in mm, K2 - leaf petiole length in mm, K3 - the distance of the widest part of the blade from the blade base (on the right side) in mm, K4 - width of the right half-blade at the height from K3 in mm, K5 - (maximum) width of the left half-blade in mm, K6 - incision of the leaf from the central nerve in mm, K7 - incision of the blade base. The second part of the research includes the measurement of heights and root collar diameters of pedunculate oak plants in the provenance test in Žepče in the spring of 2020. The provenance test was established in 2009 from seeds from the same populations and from the same trees from which the leaf material was collected for morphometric analysis. Data were processed in the statistical program SPSS 26.0. Descriptive analysis, analysis of variance, multiple Duncan test, and cluster analysis using the Average Linkage Method for the traits of the height and root collar diameter of plants in the provenance test were performed. A correlation analysis between the morphological traits of the leaves in the populations and the growth of provenances in the provenance test using the Pearson coefficient was also performed. Mutual correlations of leaf traits, correlations between height and root collar diameter of plants in the provenance test, and correlations between leaf traits and height and root collar diameter of plants in the provenance test were calculated.
Analysis of variance for the height and root collar diameter showed statistically significant differences among the investigated provenances, which was confirmed by Duncan’s test (Table 2, 3 and 4). The highest average value of plant height for 2020 had provenance Drvar (445.8 cm), followed by Jelah and Vinac, while the lowest average value had provenance Visoko - Muhašinovići (262.3 cm) (Figure 2). Overflow of provenances was registered for the height. The highest average value of root collar diameter had provenance Živinice (Figure 3), followed by the provenances Jelah and Drvar (10.7 cm), while the lowest value had provenance Nević polje (7.4 cm). The results of the conducted descriptive statistical analysis for morphological leaf traits are shown in Table 5. There was no clear pattern in the formation of groups (Figure 4), which is a consequence of the earlier historical negative effect of man on the pedunculate oak population. A significant positive correlation between height and root collar diameter was recorded at the 0.01 level (Table 6). A positive significant correlation was also registered between the height and leaf traits, except for the petiole length which did not show a significant correlation. A positive correlation was registered between the root collar diameter and all investigated leaf traits except for the petiole length and the incision of the leaf blade base of the leaf blade.
Given the obtained variability among the studied provenances, as well as significant correlations of height and root collar diameter of plants in provenance test with leaf traits, the obtained results should be used in the selection of seed trees and stands, i.e., planning measures for conservation and reintroduction of pedunculate oak in Bosnia and Herzegovina.
Key words: provenances; pedunculate oak; plant height; root collar diameter; morphometric analysis
Mirzeta Memišević Hodžić
|Oguzhan Bakan, Derya Eşen, Bilal Çetin|| UDK 630* 232.3 (001)
|Phytotoxicity of clopyralid at high rates on seed germination of mediterranean pines|
Black pine (Pinus nigra J. F. Arnold), maritime pine (P. pinaster Aiton), Scots pine (P. sylvestris L.), and Turkish red pine (TRP, P. brutia Ten.) are ecologically and economically important conifers of the Mediterranean Basin, and in particular for Turkish forestry. They are commonly used for the regeneration and restoration of degraded ecosystems in Turkey. Weeds compete with tree seedlings for vital site elements such as soil moisture and nutrients and solar radiation, substantially reducing tree establishment and growth. Herbicides can offer the practitioner efficient and cost-effective weed control compared to other methods. Rapid herbicide seed screening allows testing of crop-safe herbicides and application rates at much lower costs in a very short time-frame when compared to lengthy field trials. Clopyralid is a systemic herbicide used to rid pine seedlings of competing vegetation. The present study examined the effect of clopyralid phytotoxicity on these pine species using a rapid herbicide seed screening test in order to compare different application rates on seed germination and to identify crop-safe rates. Clopyralid was not phytotoxic to any of the pine species at low rates (i.e., <2%, v:v); however, pine sensitivity to the herbicide increased with increasing rates, especially for rates higher than 3%. Moreover, at high rates, clopyralid reduced the germination speed. This herbicide can be used at low rates for degraded areas and nursery sites in which sowing is used as the main regeneration or restoration method. Field confirmation of the obtained results is also recommended.
Key words: Forestry; forest nursery; herbicide sensitivity; Pinus; seed screening; weed control
|Osman Mujezinović, Kenan Zahirović, Mevaida Mešan, Sead Ivojević, Mirza Dautbašić|| UDK 630* 453 (001)
|Analysis of the efficacy of pheromone Trypowit for catch of Trypodendron lineatum in Bosnia and Herzegovina|
The research analyzed the catch of striped ambrosia beetle in different types of forests in Bosnia and Herzegovina. The research was conducted in the area of central Bosnia, in secondary fir and spruce forests, mixed beech and fir forests (with spruce) and forest crops. The research sample consists of 20 pheromone traps, during which the effectiveness of the pheromone attractant Trypowit was tested. The average catch of bark beetles T. lineatum for the first measurement is the highest in forest crops (792.00 beetles), for the second and third measurements in mixed beech and fir forests (with spruce) (1444.44 beetles and 1033.33 beetles). Statistical analyzes revealed the existence of statistically significant differences in the catch of T. lineatum bark beetles during the III measurement depending on the forest type.
Key words: central Bosnia; striped ambrosia beetle; forest type; pheromone traps; measurement
|Željko Španjol, Boris Dorbić, Sanja Končar, Martina Kičić, Nikola Vrh|| UDK 630* 187 + 228
|Development of holm oak (Quercus ilex L.) stands in permanent test surfaces of National park Brijuni|
The area of the Brijuni archipelago, due to geomorphological-hydrological, climatic, natural and anthropogenic influences, makes up one of a few preserved natural, cultural and landscape values in the Adriatic. In the area of Veli Brijun, there are alternating elements of several forest stand types on a relatively small surface. The anthropogenic factor influenced the disappearance of parts of forests through logging and infrastructure construction. The second factor is excessive numbers of wildlife on the island. Consequently, two test surfaces were formed intended for ecosystem monitoring on the island of Veliki Brijun: one in the fenced area of the residential park of the White Villa (No. 57) and the other in the free space in the area referred to as the Dead Peak (No. 56). The research behind this paper was conducted in May 2017 on both permanent experimental plot within which vegetative-ecological and structural features of these stands were analysed. The obtained results were compared with the most recent previous measurement of the same surfaces conducted in 1988. Based on the processed data, huge differences were identified between the measured surfaces. The floristic aspect further accentuates the differences between the two localities. In the permanent experimental plot No. 56, there is hardly any shrub layer, while in the permanent experimental plot No. 57 the latter is extremely developed. Moreover, in addition to floral scarcity on the permanent experimental plot No. 56 it is important to highlight the impossibility of natural stand regeneration, while on the permanent experimental plot No. 57 dense sprouts and young growth were recorded. Considering the measured elements of stand structure in 1988 and in 2017, the stand in the permanent experimental plot No. 57 develops and grows naturally, while the stand in the permanent experimental plot No. 56 is undergoing a phase of regression and degradation due to a large influence of wildlife. First of all, the numbers of allochthonous wildlife in the specific part of the island need to be reduced to numbers that enable stand sustainability. The permanent test surface No. 57 and the surrounding area need to be preserved as a special forest vegetation reserve and measures need to be implemented within this protection category.
Key words: NP Brijuni; forest vegetation; stand structur
ŠPANJOL, Željko ŠL