DIGITALNA ARHIVA ŠUMARSKOG LISTA
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ŠUMARSKI LIST 5-6/2022 str. 90     <-- 90 -->        PDF

the Mediterranean and North Africa (20%). On the third and fourth place (with 15%) were the groups from Europe and Euro-Asia as well as those originating from North America; the fifth place (12.5%) belonged to the group of East European, Caucasian, Minor-Asiatic and Near-Asiatic types; then came the types from the paleotropic and neotropic areas in Australia (5%). Finally, there were types from areas which were not mentioned above and which made 2.5% of the total number of the plants in the collection.
The principal purpose of the Dendropark was to serve as a teaching, research and display green area. In fact, this park has been used as an open ‘classroom’ in nature where the ecological influences and the interaction of the dendroflora and the environment have been investigated. Resistance to winter frost and summer drought, growth and development, blooming and fruitfulness, generative and vegetative reproduction within the collection, damages by insect pests and plant pathogens were studied (Em et al., 1968). Through its location, nature and mission, this small forest area is ideally suited to serve as an example of a special kind of urban green area. Urban forests undoubtedly bring many benefits: enhancing the urban landscape, increasing people’s feelings of well-being (Kaplan and Kaplan, 1989; Kuo, 2001; 2003), reducing crime (Kuo and Sullivan, 2001) and providing a multitude of ecosystem services (McPherson et al., 1994; Costanza et al., 1997). The latter includes reductions in levels of airborne particulates and other pollutants (Nowak, 1994; Freer-Smith et al., 2004; Nowak et al., 2006; Escobedo et al., 2008), diminishing so-called ‘Heat Island’ effects (Heisler et al., 1994; Deak Sjöman et al., 2015) reduced levels of energy consumption (McPherson, 1994) and alleviation of flooding events (Bolund, Hunhammar, 1999).
Because the urban green area is a dynamic matrix of biological, physical and social resources, data collection should be comprehensive and continuous to accurately reflect the complex interactions among its resource components. Comparisons of repeated inventories may be used to monitor forest health and could prevent future catastrophic damages of urban greenery.
Considering that the last inventory was done in 1967 (Em et al., 1968), and that since then the Dendropark has suffered changes in its green area, conducting a tree inventory was essential to review the current state and presence of insect pests and fungal disease. The purpose of the current study was to assess the health condition of present tree species and to indicate ones that were potentially hazardous and require removal.
Materials and Methods
MATERIJALI I METODE
The inventory was conducted in the Dendropark between March 2013 and October 2014, throughout the growing seasons. All trees were individually inventoried, assessed and recorded as described below:
– location - all trees were georeferenced and the number has been assigned to each tree (chronologically) during the data collection process;
– identification - botanical name identifies each tree (plant labels)
– health condition - the vigour and health condition of each tree was recorded as one of the following categories adapted from the rating system established by the International Society of Arboriculture® (ISA):
– Excellent- 100%-90% condition class. The tree is nearly perfect in condition, vigor and form. This rarely used category is generally applicable to small DBH trees or shrubs that have been recently transplanted and are well established. It also applies to large trees that have established themselves successfully in the landscape.
– Very Good -89%-80% condition class. Overall, the tree is healthy and satisfactory in condition, vigor, and form. The tree has no major structural problems, no mechanical damage, and may only have insignificant aesthetic, insect, disease, or structure problems.
– Good -79%-61% condition class. The tree has no major structural problems, no significant mechanical damage, may have only minor aesthetic insect, disease, or structure problems, yet is in good health.
– Fair -60%-41% condition class. The tree may exhibit the following characteristics: minor structural problems and/or mechanical damage, significant damage from non-fatal or disfiguring diseases, minor crown imbalance or thin crown, or stunted growth compared to adjacent trees or shrubs. This condition can also include trees that have been topped, but show reasonable vitality and show no obvious signs of decay.
– Poor -40%-21% condition class. The tree appears unhealthy and may have structural defects such as codominant stems, severe included bark, or severe trunk and/or limb decay. A tree in this category may also have severe mechanical damage, crown dieback, or poor vigor threatening its ability to thrive. Trees in poor condition may respond to appropriate maintenance procedures, although these procedures may be cost-prohibitive to undertake.
– Critical -20%-1% condition class. The tree has a major structural problem that presents an unacceptable risk, has very little vigor, and/or has an insect or disease problem that is fatal and, if not corrected, may threaten other trees on the property.
– Dead -0% condition class. This category refers to dead trees only.
Trees were surveyed for the presence of symptoms and signs of diseases on the base of a visual observation. Samples