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Dendrochronology, the science of dating tree rings in the wood, defines in which calendar year a particular tree ring was formed. The method can be used to determine the age and authentication of wooden musical instruments. We present a protocol describing how to perform a dendrochronological analysis on stringed instruments and how to interpret the dating. The protocol describes the basic steps in the analysis of top plates, which are usually made of Norway spruce (Picea abies) or, more rarely, silver fir (Abies alba). First, the top plate is carefully inspected, and then the tree ring widths are measured directly on the instrument using high-resolution images. After completing the measurements, a tree ring sequence of the instrument is created, and, in the next step, dating is performed with a number of reference chronologies of the tree species from different geographical areas and instruments. The specialists who date the instruments also invest work in creating reference chronologies. The dendrochronological report provides the dating of an instrument as a calendar year (end date), indicating the year in which the last (most recent) tree ring on the top plate was formed when the tree was still alive. The end date represents the terminus post quem, the year after which the instrument was made or before which it could not have been made. To estimate the year of manufacture, one must consider the time required for wood drying and storing and the number of tree rings removed during wood processing. This protocol is intended to help those commissioning such an analysis to better understand how the analysis is performed and how to interpret the dendrochronological reports in terms of the age, origin, maker, and authenticity of the instrument.

In the future, climate change is expected to affect the spatial distribution of most tree species in Europe. The European beech (

Six broadleaf tree species (Celtis australis L. – Mediterranean hackberry, Quercus petraea (Matt.) Liebl. – sessile oak, Fagus sylvatica L. – European beech, Prunus avium L. – wild cherry, Juglans regia L. – Persian walnut and Acer pseudoplatanus L. – sycamore maple) were planted in 2012 in a trial in the Slovenian Karst on two sites differing in productivity to test their suitability for use in the conversion of old pine stands into ecologically more stable broadleaf forests and to investigate their possible response to the harsher growth conditions predicted in the future. The selected economically interesting tree species have higher timber quality than broadleaves which regenerate naturally (e.g., Ostrya carpinifolia, Fraxinus ornus, Quercus cerris). Measurements were taken in 2017, after four growth seasons. All planted species except Fagus sylvatica had a high survival rate. In total, 70% of all seedlings survived, which shows promising potential. The survival rate was higher at the site on flat terrain than at the site on a slope. Prunus avium was the most successful of all planted species in terms of survival rate, at 83%, and other measured parameters (height, height increment, stem diameter, vitality and quality), and Fagus sylvatica was the least successful, with a survival rate of only 20%. Celtis australis had the highest survival rate, at 87%. Acer pseudoplatanus had the largest differences in measured parameters between the more and less productive sites among all planted species. Quercus petraea showed high resistance to xeric conditions and is expected to be the most successful in conversions. All planted species except Fagus sylvatica show favourable initial potential for the future conversion of Karst pine forests. Leta 2012 je bilo v poskusnem nasadu posajenih šest listopadnih drevesnih vrst (Celtis australis L. – navadni koprivovec, Quercus petraea (Matt.) Liebl. – graden, Fagus sylvatica L. – navadna bukev, Prunus avium L. – divja češnja, Juglans regia L. – navadni oreh, in Acer pseudoplatanus L. – gorski javor), ki je zajemal dve različno produktivni rastišči na Krasu v Sloveniji. Namen raziskave je bil ugotoviti katere drevesne vrste so primerne za premeno dotrajanih gozdov črnega bora v ekološko stabilnejše listopadne gozdove, hkrati pa tudi ugotoviti, ali so primerne za ostrejše rastne razmere, ki so napovedane za prihodnost. Izbrane drevesne vrste so ekonomsko zanimive in dosegajo višje vrednosti lesa na trgu kot vrste, ki se na območju naravno pomlajujejo (npr. Ostrya carpinifolia, Fraxinus ornus, Quercus cerris). Meritve so bile opravljene leta 2017, po štirih rastnih sezonah. Vse posajene sadike, z izjemo bukve, so imele visok delež preživetja. Skupno je preživelo kar 70 % sadik, večji delež preživelih je bil na rastišču v ravnini v primerjavi z rastiščem na pobočju. Glede na merjene parametre (preživetje, višina, višinski prirastek, premer 5 cm nad tlemi, vitalnost, kakovost) se je kot najuspešnejša izkazala divja češnja s 83-odstotnim deležem preživetja, kot najmanj uspešna pa navadna bukev z le 20-odstotnim deležem preživetja. Najvišji odstotek preživetja je imel koprivovec (87 %). Pri gorskem javorju so se pokazale največje razlike v merjenih parametrih med bolj in manj produktivnim rastiščem med vsemi vrstami. V premenah bo predvidoma najuspešnejši graden, saj je pokazal veliko odpornost na lokalne sušne razmere. V splošnem so vse vrste, z izjemo navadne bukve, izkazale potencial za prihodnjo premeno borovih gozdov.

We present a new publicly available daily gridded dataset of maximum and minimum temperature and precipitation data covering the whole territory of Slovenia from 1950 to 2018. It represents the great variability of climate at the crossroads between the Mediterranean, Alpine and continental climatic regimes with altitudes between 0–2864 m a.s.l. We completely reconstructed (quality control and gap filling) the data for the three variables from 174 observatories (climatological, precipitation and automatic stations) with the original records all over the country. A comprehensive quality control process based on the spatial coherence of the data was applied to the original dataset, and the missing values were estimated for each day and location independently. Using the filled data series, a grid of 1×1 km spatial resolution with 20 998 points was created by estimating daily temperatures (minimum and maximum) and precipitation, as well as their corresponding uncertainties at each grid point. In order to show the potential applications, four daily temperature indices and two on precipitation were calculated to describe the spatial distribution of (1) the absolute maximum and minimum temperature, (2) the number of frost days, (3) the number of summer days, (4) the intensity of precipitation and (5) the maximum number of consecutive dry days. The use of all the available information, the complete quality control and the high spatial resolution of the grid allowed for an accurate estimate of precipitation and temperature that represents a precise spatial and temporal distribution of daily temperatures and precipitation in Slovenia. The SLOCLIM dataset is publicly available at https://doi.org/10.5281/zenodo.4108543 and http://www.sloclim.eu (last access: 10 June 2021) and can be cited as Škrk et al. (2020).

Temporal variability of leaf senescence (autumn phenology) was observed in 2020 in 11 European beech (Fagus sylvatica) trees in Tivoli, Rožnik and Šišenski hrib Landscape Park in Ljubljana, Slovenia, previously this year observed also for spring phenology. General leaf colouring (LC) BBCH94 occurred, between 19 and 24 October 2020, with lower inter-individual variability than that of leaf unfolding (LU), BBCH11. The trees had active leaves (LC-LU) between 177 and 199 days. In only 3 trees total leaf fall (LF), BBCH97, occurred before 19 November 2020. LC of the tree included in the long-term monitoring program of the Slovenian Environment Agency ARSO occurred on 24 October 2020. This is 7 days later than 65-year average of the same tree/location and is ascribed to weather conditions. Investigation of tree tissues showed that the width of the last formed tree-ring in the wood varied between 0.39 and 9.61 mm and in phloem between 0.09 and 0.26 mm and that the tissues reflect health condition of the trees. V letu 2020 smo spremljali jesensko fenologijo listov 11 dreves evropske bukve (Fagus sylvatica) v Krajinskem parku Tivoli, Rožnik in Šišenski hrib v Ljubljani, Slovenija. Pri istih drevesih smo spomladi spremljali proces olistanja. Splošno obarvanje listov (LC), BBCH94, je nastopilo med 19. in 24. oktobrom 2020, v ožjem časovnem intervalu kot spomladansko olistanje (LU), BBCH11. Drevesa so imela aktivne liste (LC-LU) od 177 do 199 dni. Samo s 3 dreves je do 19. novembra 2020 odpadlo vse listje (LF), BBCH97. Pri drevesu, ki je vključeno v dolgoletni program spremljanja fenologije listov Agencije Republike Slovenije za okolje ARSO, je obarvanje listov nastopilo 24. oktobra 2020, kar je za 7 dni kasneje od 65-letnega povprečja za isto drevo / lokacijo. Raziskave drevesnih tkiv so pokazale, da je znašala širina zadnje branike v lesu med 0,39 in 9,61 mm in v floemu med 0,09 in 0,26 mm in da tkiva nakazujejo zdravstveno stanje dreves.

V zadnjih letih beležimo izrazito povečanje števila ponudnikov del v gozdarstvu (v nadaljevanju ponudniki), kar pomeni večjo konkurenco na trgu, a hkrati terja tudi razmislek o objektivni presoji kakovosti ponudnikov. Celostnega sistema objektivne presoje kakovosti ponudnikov v Sloveniji nimamo. Pri trajnostnem gospodarjenju z gozdovi veliko število ponudnikov ne sme biti edino gonilo za povečevanje konkurenčnosti sektorja. V tujini pa tudi pri nas ima merilo najnižje cene storitev vse pogosteje opraviti z vprašanji kakovosti izvedbe del, pri čemer pa se med merila kakovosti uvrščajo tako okoljski, socialni kot tudi poslovni vidiki odnosa med naročnikom in izvajalcem del.