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“What do we want? Evidence-based science! When do we want it? After peer review!” We have come to think of peer review as the stamp of quality that separates real results from mere conjecture, but a look under the hood reveals that the participants inside of peer review are far from objective. In this book I seek to reclaim subjectivity and affirm a social mode of objectivity, which prevents peer review from overpromising and underdelivering in its vital role in knowledge production.

Summary

Distribution shift, a phenomenon in machine learning characterized by a change in input data distribution between training and testing, can reduce the predictive accuracy of deep learning models. As operator and hardware conditions at the time of training are not always consistent with those after deployment, computer vision wood identification (CVWID) models are potentially susceptible to the negative impacts of distribution shift in the field. To maximize the robustness of CVWID models, it is critical to evaluate the influence of distribution shifts on model performance. In this study, a previously published 24-class CVWID model for Peruvian timbers was evaluated on images of test specimens digitally perturbed to simulate four kinds of image variations an operator might encounter in the field including (1) red and blue color shifts to simulate sensor drift or the effects of disparate sensors; (2) resizing to simulate different magnifications that could result from using different or improperly calibrated hardware; (3) digital scratches to simulate artifacts of specimen preparation; and (4) a range of blurring effects to simulate out-of-focus images. The model was most robust to digital scratches, moderately robust to red shift and smaller areas of medium-to-severe blur, and was least robust to resizing, blue shift, and large areas of medium-to-severe blur. These findings emphasize the importance of formulating and consistently applying best practices to reduce the occurrence of distribution shift in practice and standardizing imaging hardware and protocols to ensure dataset compatibility across CVWID platforms.

Open Access
In: IAWA Journal

Summary

Girdling is often used as an experimental method to study source/sink controls of cambial growth. However, the phloem responses to girdling have not been well investigated. The aim of this research was to characterize the anatomical changes in the phloem and xylem of different species following trunk girdling. Different species of gymnosperm (Abies sibirica, Pinus sylvestris) and angiosperm (Alnus incana, Populus tremula) woody plants were selected. We girdled trunks during active growth and sampled tissues at two levels (1 cm and 35 cm) above the girdle at the end of the growing season. General responses to girdling were recorded for the studied species, such as increased phloem increments, parenchymatization of conducting tissues, reduction in the size of conducting elements, and an increase in the size of axial parenchyma cells in the phloem and xylem. We observed the suppression of xylogenesis in 3 out of 4 species. Differences in the structure of conducting tissues were found, which are due to species differences in the initial tissue structure. In gymnosperms, noticeable differences in the number of resin ducts in the xylem were observed between control and girdled trees. In angiosperms, we found the formation of cells with thickened cell walls in girdled trees (i.e., the formation of phloem and xylem fibers with thickened cell walls in aspen and sclereids in the phloem of alder). Based on the literature data, the observed responses may be due to both the wounding effect and the influence of the high sugar content above the girdle.

In: IAWA Journal

Summary

This study aimed to investigate and compare the non-anatomical characteristics of six Korean oak wood species (Quercus variabilis, Q. serrata, Q. mongolica, Q. dentata, Q. aliena and Q. acutissima) to provide identification keys and quality indices for the effective utilization of these species. Non-anatomical characteristics, including heartwood fluorescence, fluorescence and color of water and ethanol extracts, froth test, chrome azurol S test and burning splinter test, were evaluated according to the International Association of Wood Anatomists (IAWA) lists. None of the six Korean oak species displayed heartwood fluorescence or fluorescence in the ethanol extract. Only Q. serrata exhibited bright blue fluorescence in the aqueous extract. Each species showed distinct colors in both water and ethanol extracts, and the water extract of all species was darker than that of the ethanol extract. A weak positive reaction in the froth test was observed only for Q. serrata. Furthermore, Q. variabilis and Q. acutissima showed positive reactions to both heartwood and sapwood in the chrome azurol S test. The burning splinter test revealed that only Q. acutissima was transformed into charcoal. Thus, water extract fluorescence and color, ethanol extract color, froth test, chrome azurol S test, and burning splinter test can be used to identify the six Korean oak species.

In: IAWA Journal
Author:

Summary

Studies of needle xylem structure (NXS) are of importance in understanding the survival, and functioning of conifers, particularly in response to environmental stressors. Herein, I review the current state-of-the-art about the NXS of genus Pinus, focusing on the xylem, tracheid, and pit structure. Genus Pinus is one of the most important and widely distributed genera of forest trees in the Northern Hemisphere. Pine species are adapted to different soil types and extreme environments imposed by elevation and latitude. They grow successfully in the boreal forest, the Mediterranean Basin, and in mountains. The importance of NXS for long-distance water transport in trees is discussed and the relationships between xylem structure and function are highlighted. Little is known about the NXS of pines, as such information was available only for 12 pine species. Moreover, current knowledge about the NXS of pines is mostly based on Pinus sylvestris L., especially regarding the effect of environmental conditions on NXS. So far, tracheid pit structure has been investigated in only one study. Although NXS is also significantly influenced by tree age, the position of needles within the crown, as well as the location of the cross-section along the longitudinal axis of the needle, a detailed needle sampling design is often missing. Hence, it is suggested to extend future studies to other pine species to explain their resistance to drought and cold. Additionally, increasing the number of studies on adult trees and distinguishing between the different types of environmental stress that a tree can face during its life cycle would be beneficial. I strongly appeal to precise description of needle sampling, which will allow us both intraspecific and interspecific comparisons. Increasing knowledge about the NXS of pines will help to better explain their resistance to environmental stress and predict their tolerance to future climate change.

In: IAWA Journal

Summary

Systematic attribution of the wood samples collected in 1830 by Pyotr Kostromitinov, the Manager of Fort Ross, a Russian settlement on the Pacific coast of northern California, has been carried out. As some wood samples belong to the taxa that had not been described at the time of their collection, their labels provide interesting evidence for the first steps of botanical exploration of an exotic flora by the Russian colonists who were not professional naturalists. Particularly, Garrya has been recognized by them as Viburnum, Lyonothamnus as Arbutus, and Torreya as Taxus. In contrast, different species of Ceanothus have been referred not only to this genus, but also to Rhamnus and Laurus. The meanings of some Russian vernacular plant names mentioned in the published historical documents have been clarified. For instance, lavr (laurel) was used not only for California laurel Umbellularia californica, but also for some Ceanothus species (probably C. velutinus). The reference of the vernacular name chaga to Sequoia sempervirens has been confirmed. Unlike most early wood collections, Pyotr Kostromitinov’s samples are made of thin stems and branches with no conspicuous surfaces showing their wood appearance. Such pieces are hardly suitable for demonstration of aesthetic or technical properties of timber. Pyotr Kostromitinov’s samples likely represent one of the earliest cases of collecting wood as objects of particular interest for botany and, more generally, for natural history. It was an important novelty for the 1830s, as the botanical exploration of woods did not have any sufficient conceptual background in those times.

In: IAWA Journal

Summary

Wood identification, whether it involves distinguishing between known species or identifying unfamiliar wood samples, is a scientific field increasingly valuable across various disciplines ranging from biology to criminology, structural engineering, and art conservation. It carries a growing economic, commercial, social, and ecological significance. Numerous scientific methods have been employed for wood identification. Visual analysis techniques, such as macroscopy, optical microscopy, scanning electron microscopy, X-ray tomography, and computer-assisted wood identification, play a pivotal role. Analytical approaches like mass spectrometry, near-infrared spectroscopy, thermogravimetry, and DNA barcoding have also been utilised. However, chromatography stands out due to its exceptional precision in providing quantitative and qualitative results, prompting its development and widespread use. This paper offers a critical review of the role of chromatography in wood identification. Advantages are highlighted, including the capability to identify specific components unique to each wood species, thus achieving remarkable differentiation at the species level. Additionally, potential drawbacks are discussed, such as the time-intensive sample preparation procedures, mainly when dealing with materials like wood-polymer composites (WPC), and the absence of an open-source database. This comprehensive analysis aims to provide a broader perspective on the possibilities and limitations of this technique.

In: IAWA Journal

Summary

Grapevine (Vitis vinifera) is the most widely cultivated and economically relevant crop in the world, but its productivity is menaced by aridification in some wine-growing regions such as the Mediterranean Basin. The impacts of climate on vines depend on regional conditions, cultivar, and vine age, among other factors. Hence, a better understanding of vine radial-growth responses to climate in different regions is sorely needed. First, we related climate data and drought severity with a long-term series of vine leaf unfolding from NE Spain to test if climate warming is advancing the onset of the growing season. Second, we used growth rings to estimate age and quantify climate-growth relationships of vines using dendrochronology. Three sites from different designations of origin and vine varieties were studied: Logroño in northern Spain (La Rioja, Tempranillo), San Martín del Río in northeast Spain (Calatayud, Garnacha) and Anzi in southern Italy (Aglianico, Aleatico). Vine leaf unfolding occurred earlier as winter-spring conditions were warmer and drier. Vine ages ranged between 16 (Logroño, Anzi) and 56 years (S. Martín del Río), and growth rates declined in the two youngest grapevines. Ring widths varied between 1.19 (S. Martín del Río) and 1.80 mm (Logroño), with Anzi showing intermediate values (1.37 mm). February precipitation enhanced vine growth in San Martín del Río ( r = 0.64 ) and Anzi ( r = 0.49 ), whereas the correlation with soil moisture peaked in March in San Martín del Río ( r = 0.83 ). Vine growth rates positively responded to September minimum temperatures in San Martín del Río ( r = 0.51 ) and Logroño ( r = 0.50 ). Garnacha cultivar in San Martín del Río showed the highest responsiveness to water availability. Therefore, similar old grapevines from continental, seasonally dry areas could be the most negatively affected by future warmer and drier climate conditions.

Open Access
In: IAWA Journal

Summary

The ipê trees belonging to the genus Handroanthus are among the most exploited species in the Amazon Forest. However, limitations in the wood identification processes can lead to an overexploitation of a single species. We compare, macroscopically, the wood anatomy of five Amazon Handroanthus species (H. barbatus, H. capitatus, H. impetiginosus, H. incanus and H. serratifolius–Bignoniaceae). Except for H. barbatus the species are trees over 20 m tall and are used commercially. We compared leaf morphology of the two most commercially used species (H. impetiginosus and H. serratifolius), aiming to separate them in the field with identification keys. For wood macroscopical analyses, 55 samples were used; the specimens were obtained in the field and from wood collections. The dichotomous key, preferable to be used in a laboratory, enables the distinction of the five species. However, the use of this key requires more knowledge about wood anatomy, since it was necessary to use more quantitative characteristics, due to the great intraspecific variation in Handroanthus woods, also reflected in the PCA (principal components analysis) and grouping analysis. To identify the plant species H. impetiginosus and H. serratifolius, the use of axial parenchyma type and vessel characteristics were important distinguishing factors, while in leaves, the most significant features were characteristics such as leaf margin, trichomes and domatia. In addition, by focusing on these key features, a multiple access identification key was created, which simplified the identification by reducing the number of characteristics necessary for the identification, facilitating its use in the field.

In: IAWA Journal

Summary

A wood from a late Middle Eocene in-situ fossil forest in northern Peru shows affinity with Qualea (Vochysiaceae), a genus of South American lowland tropical trees, based on features including vestured pits, aliform-confluent to banded paratracheal parenchyma, and homocellular rays. Additional features suggest adaptation to dry conditions. The fossil is named as a new species within Qualeoxylon (Q. lafila). Vochysiaceae and sister-group Myrtaceae share features unique to Myrtales (vestured pits, intraxylary phloem) or common in the order (vessels generally solitary and in >1 diameter class, heterocellular rays) but in other ways are clearly differentiated. Vochysiaceae has narrow to very wide vessels with elaborated axial parenchyma and lacks most characters considered less specialized such as scalariform perforations. Myrtaceae generally has vessels with vasicentric tracheids, usually exclusively solitary, very narrow to wide, and often diagonally arranged, and includes taxa with less to more specialized features. Woods with elaborated paratracheal parenchyma and vessels wide to very wide occur in wet tropical forest environments in both families Erisma, Vochysia and Qualea/Ruizterania (Vochysiaceae) in the Neotropics and Syzygium (Myrtaceae) in the Asian tropics. The Eucalyptus spp. dominating open forests in Australia have typical myrtaceous features (including vasicentric tracheids) plus homocellular rays, whereas the eucalypt clade Angophora + Corymbia, occurring mainly in the northern, monsoonal regions of Australia, has both vasicentric tracheids and aliform to banded axial parenchyma. The fossil is an early record for Vochysiaceae and adds to indications that Vochysiaceae and sister-group Myrtaceae showed significant diversification by the late Paleogene.

In: IAWA Journal