Tilia Research Articles

New Approaches for Regeneration of an Outstanding Baroque Living Heritage, the Széchenyi Linden Allée in Hungary

Allées used to be the essential artistic tools and indispensable parts of the strictly architectural, formal Baroque gardens. Beyond the practical purposes of edging paths and garden ways for walking, hunting, or horse and carriage riding, allées played a vital role in marking visual and landscape connections and thus the spatial projection of the noble estate, its wealth, and social rank. In Historical Hungary, Baroque architecture and garden art appeared in German-Austrian and French examples in the 18th century. The Széchenyi Linden Allée is an outstanding linear garden space of Baroque Garden art at Nagycenk, West Hungary. The generous composition, created by the prominent Count Széchenyi family in the mid-18th century, has remained a magnificent entity in the landscape ever since. Despite barely two hundred years of detected or unknown environmental or habitat changes, as early as 1942, the allée received a nature conservation nomination. More than a half-century later, in 2002, the allée became a historical and landscape aesthetical heritage within the Fertő-Hanság Cultural Landscape World Heritage site. Unfortunately, the once magnificent tree lines have severely eroded in recent decades due to mature trees’ subsequent death, inadequate replacement, lack of regular maintenance and tree care, and effects of climate change. In recent years (2011, 2018), landscape and horticultural analyses and visual and instrumental tree assessments were performed to help the conservation and rebirth of the allée, maintain the mature trees, and restore the landscape within a long-term renewal plan. Along with the 2018 survey and plan, the short-term maintenance works were completed in 2019–2020. This study, based on site surveys in 2022 and 2024, aims to identify the results of the primary management, analyses the vitality of mature trees after crown reductions, and then proposes a resilient and sustainable regeneration method with the habitat, cultural, natural, and genetic heritage, and the feasible maintenance contexts in focus. As proposed in the 2018 plan, the reproduction of mature trees started in 2020 and resulted in well-developing grafts for a later allée restoration. Due to the challenges of climate change, the regeneration project requires a special, long-term restoration management plan with a special focus on the still vital and possible remaining mature trees, the well-growing individuals from previous replanting, and the nursery school seedlings conserving the genetic heritage of the Széchenyi lime trees with long-viability capacity.

Urban trees left high and dry – Modelling urban trees´ water supply and evapotranspiration under drought

Abstract Long-lasting extreme weather conditions are expected to occur more frequently in the future owing to climate change, as demonstrated by the recent heat waves. In particular, the decrease in precipitation during the summer months had a significant impact on urban tree water availability. Therefore, it is imperative to develop methodologies for determining the available water supply and evaporation rates for urban trees. We mapped data from 49 urban small-leaved linden trees with varying characteristics including groundwater levels, shading situations, tree pit sizes, pavement materials, and sealing ratios. By combining these data with an adapted Penman-Monteith method to calculate evapotranspiration, we simulated the soil water storage and evapotranspiration rates of these trees during the very dry year of 2018 as an example. Model validations were performed using lysimeter and sap-flow studies on Tilia cordata trees in 2022.
During the growing season, most trees experienced water stress on > 85% of the days because of weak precipitation events that failed to refill soil water storage. In contrast, trees with additional water supply through capillary rise reached water stress approximately 45 d later. The model results suggest that many trees will require additional water supply during predicted droughts in the future, which could have significant implications for urban forestry management. This model approach can be used to test and refine future water supply management strategies, making it a useful planning tool for improving the water efficiency of trees in urban areas and blue-green infrastructure.

Tilia trees are preferred hosts of several ectomycorrhizal Ascomycota – New insights supported by the first community study of the endemic Tilia kiusiana

Asia is the center of Tilia (Malvaceae) species diversity. However, the ectomycorrhizal (ECM) relations of Asian Tilia are scarcely studied. This study provides the first description of ECM communities of Tilia kiusiana, a rare tree endemic to southwestern Japan. Across the natural distribution of T. kiusiana, ECM fungal communities hosted by the species were investigated in three study sites: Hyōgo (H) and Yamaguchi (Y) on Honshu Island, and Ōita (O) on Kyushu Island. Using molecular methods, T. kiusiana was revealed to host a high diversity of fungi belonging to 25 ECM lineages (16, 17, and 14 lineages on sites H, Y, and O, respectively). The ECM communities of T. kiusiana and the previously studied endemic T. japonica were compared to the available data on other ECM tree genera in Japan, revealing that three Ascomycota ECM lineages (/genea-humaria, marcelleina-peziza gerardii, /tuber-helvella) show a preference towards Tilia hosts. While the total lineage richness did not differ among the compared host tree genera, Tilia communities exhibited higher effective lineage richness at higher (less sensitive to rare taxa) diversity orders. Despite their relative rarity, Tilia trees might play an important role in mixed forests: maintaining the diversity of ECM Ascomycota and potentially buffering the ECM fungal biodiversity loss in cases of ECM tree host diversity decline.

Behavior of ponkan mandarin tree canopy grafted onto rangpur lime and flying dragon rootstocks

The Rangpur lime rootstock was the basis of Brazilian citrus growing for many years. However, this rootstock has been gradually replaced due to the occurrence of Citrus Sudden Death. The Flying Dragon rootstock has stood out as one of the options for replacement as it has different characteristics, such as reducing the size of the plant. There is no information in the literature about the behavior of Flying Dragon as a rootstock for Ponkan mandarin. Therefore, the objective of this study was to evaluate the behavior of Ponkan mandarin tree canopy grafted onto Rangpur lime and Flying Dragon rootstocks concerning physiological, agronomic, and fruit quality parameters. In the experiment, productivity, soil moisture, water potential, plant height, fruit diameter, fruit length, fruit mass, fruit pH, soluble solids content, titratable acidity, and ratio were evaluated. The Flying Dragon rootstock was responsible for the decrease in average productivity in the Ponkan mandarin culture. Greater plant heights were obtained when canopies were grafted on Rangpur lime. The soluble solids content of fruits from scions grafted on Flying Dragon was higher, but the degree of uniformity of the soluble solids values obtained from the Rangpur lime tree was higher.

Phylogenetic and Pathogenic Evidence Reveals Novel Host-Pathogen Interactions between Species of Lasiodiplodia and Citrus latifolia Dieback Disease in Southern Mexico.

Mexico ranks second in the world for Persian lime (Citrus latifolia) exports, making it the principal citrus exporter within the national citrus industry, exporting over 600,000 tons per year. However, diseases are the main factor reducing production, resulting in significant economic losses. Among these diseases, fungal diseases like dieback, caused by species of Lasiodiplodia, are an emerging issue in Persian lime. Symptoms include gummosis, twig and branch dieback, cankers, the necrosis of bark and wood, fruit mummification, and tree decline. The aim of this study was to investigate the occurrence and pathogenicity of the fungal species associated with twig and branch dieback, cankers, and decline of Persian lime trees in southern Mexico, and to elucidate the current status of the Lasiodiplodia species causing the disease in Mexico. During June, July, and August of 2023, a total of the 9229 Persian lime trees were inspected across 230 hectares of Persian lime orchards in southern Mexico, and symptoms of the disease were detected in 48.78% of the trees. Branches from 30 of these Persian lime trees were collected. Fungal isolates were obtained, resulting in a collection of 40 strains. The isolates were characterized molecularly and phylogenetically through the partial regions of four loci: the internal transcribed spacer region (ITS), the β-tubulin gene (tub2), the translation elongation factor 1-alpha gene (tef1-α), and the DNA-directed RNA polymerase II second largest subunit (rpb2). Additionally, pathogenicity was assessed, successfully completing Koch's postulates on both detached Persian lime branches and certified 18-month-old Persian lime plants. Through multilocus molecular phylogenetic identification, pathogenicity, and virulence tests, five species were identified as causal agents: L. iraniensis, L. lignicola, L. mexicanensis, L. pseudotheobromae, and L. theobromae. This study demonstrates that in southern Mexico, at least five species of the genus Lasiodiplodia are responsible for dieback in Persian lime. Additionally, this is the first report of L. lignicola and L. mexicanensis as causal agents of the disease in citrus, indicating novel host interactions between species of Lasiodiplodia and C. latifolia.

From lava to leaf: Physiological responses and trace element mobility in Tilia cordata L. trees grown in volcanic ash amended urban soil

This study investigates the potential of utilizing volcanic ash (VA), classified as special waste, as an inorganic soil amendment to enhance tree growth and resilience in urban areas near volcanic regions. Lime trees were transplanted into pots filled with urban soil (Cnt) or amended with 10 % VA. Tree’s physiological traits were monitored over the growing season. Notably, VA-treated trees showed improved net CO2 assimilation (Pn) and stomatal conductance (gs) during the leaf senescent stage. The analysis of ash, and Cnt and VA soils, showed low concentrations of trace elements. In addition, trace element accumulation in the leaves of VA trees was not observed. In summer, during a 12-day drought stress test, VA-stressed trees exhibited enhanced water absorption, reduced lipid peroxidation, and higher Pn and gs values in the initial days compared to control-stressed trees. Importantly, the VA also promoted a 33 % larger tree root system, potentially enhancing drought resilience. This could offer an important advantage for trees, especially during the tree's critical establishment phase. Thus, VA could be a promising amendment for urban soils to bolster tree tolerance to drought.

Succession as a Natural Tool for Restoration of Oak—Lime Forests on Aspen-Covered Clearcuts

The genus Quercus, including species like pedunculate oak (Quercus robur L.), can play a key role in maintaining climate-resistant mixed forests due to its broad ecological spectrum and drought tolerance. Unfortunately, in some parts of Europe, clearcutting has drastically reduced the oak population. An example of this event is our survey of heritage Oak—Lime forests in European Russia, which were transformed into pure aspen stands. The aim of our study was to provide forecasts and silvicultural recommendations for the passive restoration of these forests. We took a chronosequence approach to assess changes associated with natural succession over 60 years. In our survey of the development of oaks, limes and accompanying tree species (aspen, birches, maples, elms), we used 190 plots ranging across a wide spectrum of forest disturbance due to clearcutting. We demonstrate that aspen reproduce rapidly by root suckers after cutting and occupy more than 60% of the space. But the dominance of aspen decreases continuously from the age of 30, and then the lime trees begin to dominate. Oak does not show successful natural regeneration. Therefore, we recommend planting oak seedlings or sowing acorns, i.e., active restoration, in combination with the natural restoration of lime.

Anatomy and micromorphology of Tilia species from Turkey and its taxonomic implication.

The genus Tilia L. belongs to Malvaceae and it is represented by four species in Turkey. These are T. cordata, T. platyphyllos, T. rubra subsp. caucasica, and T. tomentosa. Tilia species have medicinal importance, especially to treat colds, flu, and coughs, and are also used as sedatives. Inflorescence with bract is recorded in the pharmacopeia as used parts. This study aimed to investigate the differences in leaf and bract characteristics in distinguishing Tilia species. Leaves and bracts were examined anatomically and micromorphologically under light and scanning electron microscopes (LM and SEM). There is no comparative anatomical and micromorphological study of Tilia species from Turkey. Microscopic examination allows for the observation of stomata types, trichomes, and other anatomical structures. These features can vary among species and can aid in differentiation. Features of bract that is medicinally used part were evaluated to find efficient diagnostic characters. The leaves also possess distinct characteristics, and leaf morphology is already used in the identification key in Flora. The emphasis is on identifying the species of medically used drugs. A diagnostic key was created using LM and SEM based on bract features to differentiate taxa for the first time. RESEARCH HIGHLIGHTS: Leaf and bract anatomy of Tilia taxa was studied via LM and SEM. The raw plant material is inflorescence with bract so identification by bract is important for species adulteration. An diagnostic key based on bract features was created for the first time.

Soil respiration across a variety of tree-covered urban green spaces in Helsinki, Finland

Abstract. As an increasing share of the human population is being clustered in cities, urban areas have swiftly become the epicentres of anthropogenic carbon (C) emissions. Understanding different parts of the biogenic C cycle in urban ecosystems is needed in order to assess the potential to enhance their C stocks as a cost-efficient means to balance the C emissions and mitigate climate change. Here, we conducted a field measurement campaign over three consecutive growing seasons to examine soil respiration carbon dioxide (CO2) fluxes and soil organic carbon (SOC) stocks at four measurement sites in Helsinki, representing different types of tree-covered urban green space commonly found in northern European cities. We expected to find variation in the main drivers of soil respiration – soil temperature, soil moisture, and SOC – as a result of the heterogeneity of urban landscape and that this variation would be reflected in the measured soil respiration rates. In the end, we could see fairly constant statistically significant differences between the sites in terms of soil temperature but only sporadic and seemingly momentary differences in soil moisture and soil respiration. There were also statistically significant differences in SOC stocks: the highest SOC stock was found in inactively managed deciduous urban forest and the lowest under managed streetside lawn with common linden trees. We studied the impacts of the urban heat island (UHI) effect and irrigation on heterotrophic soil respiration with process-based model simulations and found that the variation created by the UHI is relatively minor compared to the increase associated with active irrigation, especially during dry summers. We conclude that, within our study area, the observed variation in soil temperature alone was not enough to cause variation in soil respiration rates between the studied green space types, perhaps because the soil moisture conditions were uniform. Thus, irrigation could potentially be a key factor in altering the soil respiration dynamics in urban green space both within the urban area and in comparison to non-urban ecosystems.

Foliar Impact of Urea and Nano Urea Application on Growth and Yield Attributes of Acid Lime (Citrus aurantifolia Swingle.) Cv. Kagzi

Background: Acid lime being the nutrient exhaustive fruit crop and requires regular annual application of macro and micronutrients and there was a need to study the response of foliar application of Urea and Nano urea as a source of nitrogen to assess its impact on Kagzi lime trees. The reason to undertake this research was based on response of foliar Urea and Nano urea on nutrient supplementation, rapid nutrient uptake, improved nitrogen utilization along with enhanced nutrient mobility and its effect on growth and yield attributes in acid lime cv. Kagzi plants. Methods: A field experiment was conducted at the Fruit Instructional Farm, Department of Fruit Science, College of Horticulture and Forestry, Jhalawar during June 2022 to December 2022 in established Kagzi lime orchard of 14 years age. The experiment was laid out in Randomized Block Design with three replications. The experiment consisted of foliar application of nine treatments comprising Urea and Nano urea. Result: On the basis of results obtained in the present investigation, the foliar application of T4 treatment (Urea @ 2.0%) was found beneficial in the improvement of growth and yield attributes in acid lime cv. Kagzi. The foliar feeding response through T4 treatment (Urea @ 2.0%) resulted in enhancement of plant height (m), plant spread [E-W and N-S (m)], canopy volume (m3), number of fruits plant-1, yield plant-1 (kg) and estimated yield (kg/ha) in acid lime cv. Kagzi trees.The overall maximum percentage increase in growth attributes viz. plant height (6.46%), E-W plant spread (6.09%), N-S plant spread (6.27%) and canopy volume (20.34%) were found in T4 treatment consisting (Urea @ 2.0%). The application of T4 treatment (Urea @ 2%) resulted in enhancement of number of fruits plant-1 (480.33), fruit weight (67.90 g), yield plant-1 (27.87) and estimated yield (77.21 q/ha).

Comparison of nectar and pollen resources in various Tilia species. A case study from southern Poland

Management of food resources is considered fundamental for supporting insect pollinators, whose abundance shows a downward trend on the global scale. Here, the nectar and pollen production (per flower, per 1 m2 of tree crown), the composition of nectar carbohydrates and the levels of pollen proteins was evaluated in eight Tilia species (Malvaceae) growing in SE Poland. In the warm-summer continental climate, Tilia species can improve nectar and pollen resources mainly in June/July. Although the flowering period of each species is short (8.0–14.7 days), appropriate selection of species can extend the availability of food for more than a month. However, the considerable variations in the flowering onset (11.2–20.1 days) may cause significant inter-seasonal shifts in food accessibility.The nectar with its highly changeable sugar concentration (29.5–77.4%) was composed of sucrose, glucose, and fructose; protein content in pollen was 7.2–16.8%. The mean sugar yield was in the range of 0.95–19.1 g per 1 m2 (T. amuriensis – T. platyphyllos, respectively), whereas the mean pollen yield was 1.37–4.1 g per 1 m2 of tree crown (T. amuriensis – T. × euchlora, respectively). Significant year-to-year fluctuations of sugar and pollen yield in linden trees have to be taken into account in conservation schemes, and the introduction of other flowering plants with more stable sugar and pollen production should be considered in an area with a high density of linden trees. Linden flowers mainly support honey bees; nevertheless, wild pollinators (bumble bees, solitary bees, and dipterans) can also benefit from linden floral resources.

Dieback of small‐leaved lime trees (Tilia cordata Mill.) caused by Gibsiella quercinecans in urban areas in Poland

AbstractIn the summer of 2023, small‐leaved lime trees (Tilia cordata) in the capital city of Warsaw were found to be dying along transport routes. The stem fragments collected for analysis showed the presence of necrosis near larval galleries caused by Agrilus viridis (L.). After a detailed microbiological analysis of both the tissues taken directly from the necroses and from the larval galleries, the presence of five different bacteria was confirmed, including Gibsiella quercinecans, which is responsible for the phenomenon of oak stand dieback known as Acute Oak Dieback. The pathogenicity tests carried out confirmed that this bacterium is also capable of causing necrosis on lime trees. The fact that this bacterium was found in the larval galleries of the polyphagous A. viridis could also indicate that it was vectored into the lime tree from other species, for example, oaks. The results obtained are the first report on the occurrence of G. quercinecans on lime trees in Poland.

Poppies and Women Under the Linden Tree in a Slovak Village

In her 1993 book, ‘What This Awl Means’, Jane Spector examined the relationship between gender, objects, environment and archaeology through a female personal narrative. While such historical storytelling has been viewed as unconventional, it is effective as it paints a vibrant picture communicating context, significance and insight into what might otherwise be viewed in traditional archaeological description as a simple, utilitarian tool. However, to do this effectively, sufficient cultural competence and symbolic understanding must be woven with archaeological research, anthropological interpretation and understanding of the cultural and historical context through the lens of storytelling. This paper explores this approach by presenting the complex symbolic and agroeconomic relationships maintained with the opium poppy (Papaver somniferum L.) and the linden tree (Tilia sp.) by ancient peoples in Central Europe. The story draws on a body of archaeological, botanical and chemical research, Slovak cultural and linguistic background, as well as ancestral oral history.

Colletotrichum cliviicola as a new causal agent causing leaf spot disease on Tilia tomentosa moench (silver linden) in China

Tilia tomentosa Moench (silver linden) is a globally preferred option for landscaping and street tree planting. Its intentional introduction to China in recent years has led to widespread cultivation. In 2021, a leaf spot disease significantly impacted silver linden trees in a sentinel garden in China, with an average incidence and disease severity of 94.3% and 5.0, respectively, adversely affecting the trees' growth and development. In this investigation, potential fungal pathogens were isolated from the affected leaves, and Koch's postulate was subsequently employed to validate the pathogenicity of the fungal isolates (TM-1 and TM-2). The pathogen was unequivocally identified as Colletotrichum cliviicola through a combination of morphological observation and a multi-locus analysis (ITS, ACT, ApMat, CAL, CHS-1, GAPDH, and TUB2). This marks the first record of C. cliviicola affecting silver linden in China. The information provided a valuable foundation for the rapid detection and effective prevention and control of the diseases affecting linden trees.

Повесть И. С. Тургенева «Первая любовь»: на границах идиллии

The paper is dedicated to analysing Ivan Turgenev’s novella “First Love” (1860), which has not undergone detailed philological scrutiny before. The research aims to identify the border phenomena of the idyllic discourse and its specificity. The scientific novelty of the paper lies in examining the boundaries of the idyllic through the analysis of characters, chronotopes, and the motif system in the novella. The research findings revealed that in Turgenev’s work, all types of idyll – rural, familial, and romantic – are seemingly present, but they are only represented at the level of genre-specific features (beautiful nature, youthful age, first love). The novella represents a recollection, reflection, a turn to the “golden age” of the hero’s youth, his first infatuation, thus demonstrating elegiac traits. Through the lens of idyllic images, motifs, and details of the chronotope, their quasi-significance is seen. Semantic signs (the garden, linden trees, alleys) serve as substitutes for unrequited love. Details of “locus amoenus” are merely symbols linking the author’s work to the idyllic tradition, but in reality, they deviate from reader expectations and demonstrate the opposite of an idyllic world perception.

Rainfall interception by urban trees: Event characteristics and tree morphological traits

AbstractThe rapid expansion of impermeable surfaces in cities has a major impact on urban hydrology by reducing rainwater infiltration and increasing runoff rates and peaks. The use of urban trees as stormwater management tools is gaining recognition for their potential to mitigate flood risk and provide additional ecosystem services. We conducted an in‐situ field experiment to measure throughfall on Norway maple (Acer platanoides) and small‐leaved lime (Tilia cordata) to assess the interception capacity of solitary urban trees under different degrees of surface sealing in the city of Freiburg, Germany. We examined the relationships between rainfall characteristics, tree morphological traits, and the interception behaviour, analysing eight trees per species over 76 recorded rainfall events from April to September 2021. Average interception values were higher for small‐leaved lime trees (70.3% ± 6.6%) than for Norway maple (54.8% ± 10.3%) surpassing those in typical forested environments. The average interception loss of all recorded events was 2.6 ± 0.6 mm for Norway maple and 3.7 ± 0.3 mm for small‐leaved lime. For both tree species, significant linear correlations were found between the relative interception and factors such as rainfall depths, the leaf area index (LAI), and the plant area index (PAI) (adj. R2 >0.45). Unlike Norway maple, small‐leaved lime demonstrated significant relationships between several tree morphological parameters and interception (adj. R2 >0.43). The LAI of both species significantly decreased with the increasing degree of surface sealing, which in turn affected interception rates. Our results enhance the understanding of the interception process by solitary trees in urban contexts and enables the parameterization of interception rates using measurable properties. To develop a comprehensive database for modelling parameters and aid urban planners in stormwater management, further field experiments involving various tree species are essential.

ACCUMULATION OF ORGANOCHLORINE PESTICIDES IN MEDICINAL PLANT RAW MATERIALS OF THE VORONEZH REGION

The purpose of the study is to examine the peculiarities of accumulation of the most dangerous organochlorine pesticides in medicinal plant materials of Voronezh region agrocenoses.
 Materials and Methods. The author analyzed pharmacopoeial species of medicinal plant raw materials, widespread in central Russia. The plants belong to both natural plant communities and synanthropic vegetation: common nettle leaves, common plantain leaves, ginger plant flowers, small-leaved lime flowers, quinquelobate motherwort herb, absinthium herb, common yarrow herb, knotgrass herb, common burdock roots, and common dandelion roots. Samples of the surface soil were also taken. The author determined dichlorodiphenyltrichloroethane, hexachlorocyclohexane, hexachlorane, and aldrin content in medicinal plant raw materials and surface soil. The studies were carried out on a Tsvet 500M gas chromatograph with a microsyringe dispenser, glass capillary separation columns and flame ionization detection.
 Results. Studies of surface soil samples and medicinal plant raw materials showed the virtual absence of organochlorine pesticides in the analyzed materials: the content of hexachlorocyclohexane and its isomers (total) was less than 0.001 mg/kg, the content of dichlorodiphenyltrichloroethane and its metabolites (total) was less than 0.007 mg/kg. Aldrin and hexachlorane were not detected. The results obtained favorably distinguish the Voronezh region from other constituent entities of the Russian Federation, where high concentrations of organochlorine pesticides are periodically detected both in soil and in plants. This fact opens prospects for the cultivation and procurement of wild plants in the Voronezh region.

Freedom Trees

Abstract: An essay using the image, history, and cultural connections of the linden tree to examine its role within countries and historical events. The linden tree is considered the oldest tree in the world and has been witness to several of history's definitive moments. The author describes how different cultures have utilized the help of the linden trees through its natural properties. In juxtaposition, there is an examination on the impact of the empires on the lindens and the current livelihood these empires provide the narrator. The author also uses this collected history to examine their connection to the linden tree through personal anecdotes while living in Philadelphia.

Designing a territorialized work system as the making of a milieu.

A huge amount of ergonomic research has been carried out in companies. However, territory is now becoming a new frontier for decision-making during design. This article aims to examine how territorial scale impacts the design process of a work system. Two types of methods were used. First, we analyzed and defined what constitutes a territorialized work system. On this basis we conducted a design project for the re-conception of a territorialized work system with the linden tree. It is argued that a "territorialized work system" is not limited to its productive dimensions; it engages in a "making of a milieu" which consists of matching the work system with a range of dimensions that make life possible within the territory. The territorial aspect of running a design project thus relates to three dimensions: the systemic dimension of the system to be designed, the organization of the design project itself, and the nature of the object to be designed: the possibility of making a milieu, i.e. of being able to live in the territory.

A multi-criteria drought resistance assessment of temperate Acer, Carpinus, Fraxinus, Quercus, and Tilia species

A rapidly warming climate with growing frequency of hot droughts urges Central Europe’s forestry sector to adapt to increasing climatic stress. One option is to choose native minor timber species with assumed higher stress tolerance; yet, information on the drought resistance of many species is scarce. We examined the drought resistance of adult trees of Norway maple (Acer platanoides), European hornbeam (Carpinus betulus), Common ash (Fraxinus excelsior) and Little-leaved lime (Tilia cordata) at leaf, branch, stem and root levels, combining studies on leaf water status, branch xylem hydraulics, fine root vitality and radial stem growth, for deriving an evidence-based drought resistance ranking of the species. Results were compared to Sessile oak (Quercus petraea), a fairly drought-resistant major timber species. All species showed constant growth rates despite increasing climatic aridity, indicating low climate vulnerability. Foliage loss after the severe 2018/19 drought increased in the sequence Quercus < Fraxinus < Acer < Tilia < Carpinus. The water potential at leaf turgor loss (PTLP) was no suitable indicator of the species’ climate-sensitivity of growth or drought-induced foliage loss. The growth performance of Tilia demonstrates that some angiosperm trees can achieve a fairly high degree of drought resistance through plant-internal water storage and high leaf tissue elasticity, despite a small hydraulic safety margin and high PTLP. Drought resistance as deduced from growth performance and defoliation after severe drought decreased in the sequence Quercus > Fraxinus & Acer > Tilia > Carpinus. We conclude that Acer, Carpinus, and Tilia (and Fraxinus, despite being often Hymenoscyphus-infected) are suitable timber species for Central Europe’s forestry sector in a drier and warmer climate.