Arboristična preiskava plečnikovih vrb v Trnovskem pristanu v Ljubljani : diplomsko delo - univerzitetni študij

Lestan, Jakob Žiga (author), Oven, Primož (mentor)

Na raziskovalni ploskvi Trnovski pristan v Ljubljani je bila potrebna obnova drevoreda 31 pobešavih vrb. Pred posekom 19 dreves je bilo analiziranih 28 obstoječih dreves. Izmerili so bili obseg, premer in višino, ter vizualno ocenili njihovo vitalnost. Pri vsakem drevesu so pregledali strukturne napake in stanje primerjali s popisom iz leta 2000. Med posekom so odvzeli kolute dvanajstih dreves in enajst vej. Na kolutih so prešteli letnice, izmerili polmer, debelino zdravega lesa, debelino žive in mrtve skorje. Pri vejah so prešteli letnice v prevalitvah, izmerili premer nepreraslega dela, premer stare veje, premer nove veje, premer razkroja in diskoloracije in debelino prevalitve. Vsa drevesa so od zadnjega popisa beležila debelinsko, dve tretjini pa tudi višinsko rast. Krošnje vseh dreves so bile sekundarne, vrhovi so bili pri polovici dreves suhi, v vseh drevesih pa so bile po celotnem drevesu prisotne glive. V splošnem je bilo stanje dreves v letu 2007 bistveno slabše od stanja, ki je bilo evidentirano leta 2000. Delež zdravega lesa je znašal največ 2 %. Ocene starosti rezov vej so znašale v povprečju 12 let. Analiza je pokazala, da je ob večji preraščenosti reza obseg diskoloracije manjši in da s premerom odžagane veje narašča obseg diskoloracije. Za nova drevesa se priporoča redčenje krošenj vsake tri do štiri leta, pri tem se lahko odstrani največ ena četrtina krošnje, premer odžaganih vej pa ne sme presegati 5 cm.

• Language: Slovenian
• Keywords: Trnovski pristan, pobešava vrba, Salix x sepulcralis, arboristika, stanje dreves, Ljubljana
• Work type: Undergraduate thesis
• Typology: 2.11 - Undergraduate Thesis
• Organization: BF - Biotechnical Faculty
• Place of publishing: Ljubljana
• Publisher: [J. Ž. Lestan]
• Year: 2010
• Number of pages: XI, 101 f.
• PID: 20.500.12556/RUL-17757
• UDC: 630*27(043.2)=163.6
• COBISS.SI-ID: 3083174
• Publication date in RUL: 11.07.2014

Secondary language

• Language: Unknown

Abstract

The famous willow tree promenade in Trnovski pristan in Ljubljana consists of 31 willow trees that needed to be replaced. Before the cut down 28 standing trees were analyzed, 19 of which were later replaced. The circumference, the diameter and the height of the trees were measured and the visual evaluation of the vitality of the trees was conducted. Each tree was checked for structural defects and the current condition of trees was compared to their 2000 state. The samples of 12 trunk discs and 11 branches were taken during the felling. Annual rings were counted on the trunk discs in addition to the measurements of radius and thickness of intact wood, inner bark and outer bark. The annual rings of the branches in the wound-wood were counted as well as the diameters of both old and new branches, the extent of discoloration and decay and the thickness of wound-wood were measured. It was established that all trees got thicker and two thirds got higher by the time the last condition has been checked. All the crowns were secondary and more than half of the trees had dead crown tops. All the trees were also infected with fungi.The condition that the trees were in established in 2007 was generally worse than the one in 2000. The percentage of healthy wood was nowhere bigger than 2 %. The age of cut branches was estimated to be approximately 12 years. It was also determined that the extent of discoloration decreases with increasing wound closure, whereas the discoloration increases with the thickness of the pruned branch. It is recommended that the newly planted trees have their crowns thinned once every three to four years and the cuts are not allowed to be thicker than 5 cm; not more than a quarter of the crown should be removed as well.