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We monitored six healthy dominant trees and six girdled Scots pine trees for two successive growing seasons (2014 and 2015) to investigate the seasonal dynamics, cambial activity, and morphology of the new xylem and phloem cells formed under environmental stress when girdling was applied during the dormant period (15 January 2014). Microcore (1.8 mm) samples were collected weekly using a Trephor tool above and below the girdling area, and weather data were measured on site. Drought stress in combination with girdling reduced the total number of differentiation days cell formation. In 2014, no significant differences in tracheid dimensions were observed between the girdled area and the control trees, while in 2015, the control trees showed significantly smaller cell wall thickness and radial dimensions of the latewood tracheids (LW) compared to 2014 and girdled trees had no occurrence of LW. Under stressful heat waves and prolonged periods of no precipitation, the trees tended to reduce the number of tracheids that were formed and exhibited smaller radial dimensions (narrower tree rings) to increase their hydraulic efficiency. Trees responded to limited water availability by forming intra-annual density fluctuations (IADFs L) in the zone of the LW to overcome stressful conditions. Although xylem cell differentiation was affected by stressful conditions, no significant variability in phloem cell dimensions was observed. Thus, the phloem tissue was less sensitive to exogenous factors.

Hand spinning has become increasingly popular as a recovery of the traditional techniques of natural fibre processing and cultural heritage protection. Modern spinning wheels are usually made of easily available wood species, particularly hardwoods, and one spinning wheel usually consists of one or two species. However, the wood species that were used for the individual parts of old spinning wheels in Central Europe are still unknown. To improve our understanding of traditional craftsmen and their skills, we investigated old spinning wheels that originated from Central Europe in the 19th and the 20th century. In this study, we present a collection of 643 samples from 54 artefacts representing the region between the European Alps and the Western Carpathians. Spinning wheels were usually made of 3 to 5 wood species, and the species selection varied among regions. Generally, high wood density (> 600 kg.m−3) species prevailed in Austria and Western Slovakia, but lower wood density (< 600 kg.m−3) species were preferred in the south-eastern Czech Republic. Easily workable species were used for the production of the spinning wheels, primarily Tilia, Fagus sylvatica, Picea abies, and Acer. In addition to these species, a high proportion of fruit-bearing trees and three shrubs were identified. Wood anatomy, as an important scientific method, contributed to understanding the reasons for species selection and the suitability of their properties which will enable the conservation of sustainable folk traditions and crafts, as well as the knowledge of traditional craftsmen.

We studied the effect of local weather conditions on intra-annual wood formation dynamics and wood structure of European beech (Fagus sylvatica L.) from a temperate location in the Czech Republic in two consecutive years, 2010 and 2011, characterized by different amounts of precipitation. Microcores were taken at weekly intervals and transverse sections of cambial and xylem tissue were prepared for light microscopic observation. Air temperature and soil moisture content were measured daily at the research plot. Tree-ring formation patterns and vessel features showed different responses to climatic factors in the two years. In 2010, the onset of cambial cell production occurred almost 10 days later than in 2011, when a considerably reduced amount of rainfall was already observed in the winter and spring months, as shown in Standardized Precipitation Index (SPI) values. Lack of precipitation in 2011 caused premature cessation of cambial cell division and markedly narrower annual xylem increments. Vessel density and water conductive area were higher in 2011 than in 2010. Average vessel size in general did not change. In response to local weather conditions, beech controls its hydraulic conductivity mainly by changing the number of vessels and tree growth rate, followed by vessel size. The lower sensitivity of vessel diameter to hydrological alterations confirms previous studies by other authors.

Given recent climatic trends, it is crucial to understand the plasticity and adaptiveness of forest trees in order to evaluate their current and future responses to changing climatic conditions. We investigated inter- and intra-annual xylem growth and its relation to weather factors in European beech ( Fagus sylvatica ) and a co-occurring conifer, either Norway spruce ( Picea abies ) or Scots pine ( Pinus sylvestris ), at five sites with different elevations and climatic conditions, in Spain, Slovenia and the Czech Republic. The selected sites were located in central and marginal parts across the distribution range of the investigated species. The results showed that climate-growth relationships vary between different species at the same site and within the same species at different sites, indicating diverse survival strategies among the observed species but also high plastic capacity within the same species. Moreover, xylogenesis analysis revealed the capacity of trees to adapt the beginning and cessation of wood formation depending on conditions. In case of beech, shortening growth duration in dryer and warmer environments and the opposite in the case of conifers, with which the growing period was extended in such conditions. Consequently, the plasticity capacity of beech was limited due to short growth duration, while conifers (especially pine) proved to be able to compensate climatic constrictions by growing over a longer period and becoming more adapted to survival in drought-prone environments.

Despite its major economic importance and the vulnerability of Picea abies (L.) H. Karst. to climate change, how its radial growth at intra-annual resolution is influenced by weather conditions in forest stands with a high production capacity has scarcely been explored. Between 2009 and 2011, phenological variation in seasonal cambial cell production (CP) was analysed in adult P. abies trees from three contrasting sites, differing in altitude and latitude. The results indicate that the timing of cambial CP is a highly synchronic process within populations since in all cases the cambium simultaneously started and stopped producing xylem and phloem cells. Our results also demonstrate that the phenology of cambial CP is highly variable and plastic between years, depending on seasonal temperature and precipitation variation. Differences among sites, however, are only partially explained by different environmental (elevation and altitude) and climatic conditions, suggesting that local adaptation may also play a decisive role in the strategy of P. abies for adapting wood and phloem increments to function optimally under local conditions.

The differences in the microscopic structure of wood based on the variables of earlywood vessel area and tree ring width were analysed in 6 trees of Pedunculate oak (Quercus robur L.) and 6 trees of Sessile oak (Quercus petraea (Mattuschka) Liebl.) in the same forest stand at a site in the Vizovice Highland (Czech Republic). The aim of this paper was to assess any differences between the two oak species when grown in the same location. Also the effect of tree-ring width and the effect of age on earlywood vessel variables were analysed. Mean values of tree-ring widths were not different between species. Earlywood vessel area chronologies were synchronized well between species. The mean values of earlywood vessel area (average vessel area, average vessel area of the first row of vessels, area of the largest vessel) showed a significant difference. Finally, we can conclude that there were differences in vessel features between these oak species.

Temperature, water availability and photoperiod are the primary drivers of tree phenological processes. However, there is lack of information how the spring temperature and summer drought affect phenology of both cambium and needles. We evaluated the interplay between xylem and needle development of mature Scots pine trees in three consecutive years differing in the spring temperatures and onset and duration of summer drought. Cambial activity began on the day of a year (DOY) 83–87, while the bud break occurred on DOY 113–119, when also the secondary cell wall of tracheids started its formation. While the timing of bud break correlated with the sum of effective temperatures, the beginning of cambial zone activity did not. The needles were fully unfolded around DOY 170, which corresponded to the transition between earlywood and latewood tracheids. Summer drought did not affect needle development, but it changed the rate of production and morphology of latewood tracheids. Latewood tracheids from the year 2015 when the drought was longest (i.e. until the second half of August in 2015 compared to the duration from June until the middle of July in the two other years) were 32% narrower and they had 34% thinner cell walls than in 2014 and 2016. The improvement of tree water status in July resulted in the formation of intra-annual density fluctuations (IADF). The interplay between needle and cambium phenology provided an insight into how the tree allocates the resources with varying temperature and soil water availability.

The dynamics of xylem formation in young Norway spruce (Picea abies (L.) Karst.) trees was analysed during one growing season in Rajec-Němčice in the Czech Republic. Microcores were taken from six 34-year-old trees in April to October 2009 at weekly intervals by means of a Trephor tool in a second generation spruce monoculture stand. The cambium activity started between 16–30 April and the last cells divided between 27 August and 17 September. The average length of cambium activity was 5.2 months. The cambium achieved its maximum width (12.3 cell layers) in June, whereas the dormant cambium contained 5.3 cell layers on average. Fitting the xylem increments to the Gompertz function showed that the period of most intensive cell formation was at the beginning of July. The total time necessary for the development of most cells was 156 days when modelled with WCDcalc script and 117 days when modelled with the Gompertz function.

The processes of xylogenesis are very often studied with use of repeated micro-sampling method. Microcores are taken throughout the growing season. After paraffin embedding and cutting on a rotary microtome permanent microslides are prepared. The numbers of cells (tracheids) are counted for each of the three zones – radially enlarging (G), maturing (D) and matured (T) zone of the developing growth ring. These numbers of cells are an input for the R script named WCDcalc that was developed for the calculation of durations and timing of cell differentiation in developing growth rings of softwoods. WCDcalc produces a plain text file as an output and a bar plot. For each cell there is a date in day of year format (DOY) that represents the day when the cell entered the particular zone, and the duration for which the particular cell was in the zone of the developing growth ring. The bar plot interprets results graphically in two forms. First, it is shown on the display, second, it is saved as an EPS file.WCDcalc is an R script written in R language. It can be run only in R environment. WCDcalc ( http://xylogenesis.wz.cz ) was released under GNU General Public License.

The first permineralized angiosperm wood from the Cenomanian of the Bohemian Cretaceous Basin (Czech Republic) is described. The wood is diffuse porous, with vessels solitary and in radial multiples of 2–5, perforation plates are exclusively simple, and tyloses abundant. Rays are usually 4–7-seriate and heterocellular, narrower rays are rare. The fossil is designated as Paraphyllanthoxylon aff. utahense Thayn, Tidwell et Stokes. Other occurrences of Paraphyllanthoxylon are reviewed and the equivocal botanical affinity of the taxon is discussed.

There is limited information on intra-annual plasticity of secondary tissues of tree species growing under different environmental conditions. To increase the knowledge about the plasticity of secondary growth, which allows trees to adapt to specific local climatic regimes, we examined climate–radial growth relationships of Norway spruce [Picea abies (L.) H. Karst.] from three contrasting locations in the temperate climatic zone by analyzing tree-ring widths for the period 1932–2010, and cell characteristics in xylem and phloem increments formed in the years 2009–2011. Variation in the structure of xylem and phloem increments clearly shows that plasticity in seasonal dynamics of cambial cell production and cell differentiation exists on xylem and phloem sides. Anatomical characteristics of xylem and phloem cells are predominantly site-specific characteristics, because they varied among sites but were fairly uniform among years in trees from the same site. Xylem and phloem tissues formed in the first part of the growing season seemed to be more stable in structure, indicating their priority over latewood and late phloem for tree performance. Long-term climate and radial growth analyses revealed that growth was in general less dependent on precipitation than on temperature; however, growth sensitivity to local conditions differed among the sites. Only partial dependence of radial growth of spruce on climatic factors on the selected sites confirms its strategy to adapt the structure of wood and phloem increments to function optimally in local conditions.

Wood is the main terrestrial biotic reservoir for long-term carbon sequestration(1), and its formation in trees consumes around 15% of anthropogenic carbon dioxide emissions each year(2). However, the seasonal dynamics of woody biomass production cannot be quantified from eddy covariance or satellite observations. As such, our understanding of this key carbon cycle component, and its sensitivity to climate, remains limited. Here, we present high-resolution cellular based measurements of wood formation dynamics in three coniferous forest sites in northeastern France, performed over a period of 3 years. We show that stem woody biomass production lags behind stem-girth increase by over 1 month. We also analyse more general phenological observations of xylem tissue formation in Northern Hemisphere forests and find similar time lags in boreal, temperate, subalpine and Mediterranean forests. These time lags question the extension of the equivalence between stem size increase and woody biomass production to intra-annual time scales(3, 4, 5, 6). They also suggest that these two growth processes exhibit differential sensitivities to local environmental conditions. Indeed, in the well-watered French sites the seasonal dynamics of stem-girth increase matched the photoperiod cycle, whereas those of woody biomass production closely followed the seasonal course of temperature. We suggest that forecasted changes in the annual cycle of climatic factors(7) may shift the phase timing of stem size increase and woody biomass production in the future.

A multi proxy approach was applied in the reconstruction of the architecture of Medieval horse stable architecture, the maintenance practices associated with that structure as well as horse alimentation at the beginning of 13th century in Central Europe. Finally, an interpretation of the local vegetation structure along Morava River, Czech Republic is presented. The investigated stable experienced two construction phases. The infill was well preserved and its composition reflects maintenance practices. The uppermost part of the infill was composed of fresh stabling, which accumulated within a few months at the end of summer. Horses from different backgrounds were kept in the stable and this is reflected in the results of isotope analyses. Horses were fed meadow grasses as well as woody vegetation, millet, oat, and less commonly hemp, wheat and rye. Three possible explanations of stable usage are suggested. The stable was probably used on a temporary basis for horses of workers employed at the castle, courier horses and horses used in battle.