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BACKGROUND The significance of morphological responses of hosts on susceptibility against gall‐inducing insects is relatively unknown, especially in planted forests. Here, we investigate the temporal morphological responses (gall development) induced by the invasive gall wasp Leptocybe invasa and the subsequent insect development in two Eucalyptus clones. RESULTS: Our results identified a novel stage of gall development, not previously reported, termed here 'brownish ring'. In both hosts similar gall development stages were observed. Although L. invasa oviposited in both clones, comparison of external morphological traits of galls over time revealed a differential response in the number of galls between clones. Comparison of the developmental time of each gall and insect stage between clones suggests that plant defense mechanisms against L. invasa are activated shortly after oviposition by the wasp, yet before gall formation. CONCLUSION: Gall number is an important parameter that should be used to measure host susceptibility among Eucalyptus clones. To the best of our knowledge, this is the first study showing differential morphological responses induced by a galling insect, even before gall formation, revealing differences in susceptibility between different plant hosts. These findings provide insight into the use of early stages of gall formation by L. invasa to prevent invasion and establishment of this pest. [ABSTRACT FROM AUTHOR]

Globally, about 20 million ha of land area is occupied by plantations of Eucalyptus. Motor-manual tree harvesting techniques (using chainsaws) are still applied in eucalypt plantations, especially in difficult terrains or for large-sized trees where mechanised felling may not be an effective and safe possible option to apply. There is little information available on motor-manual felling in eucalypt stands. This article reviewed available literature on the productivity of motor-manual felling. The results were classified into four regions, including Africa, Asia/Oceania, America and Europe. Results of international studies indicate that the main factors impacting the productivity of motor-manual felling include diameter at the breast height (DBH), travelling distance to trees, understory density and terrain slope. Operator experience also plays a key role in felling operations. The range of reported productivity varied from 0.6 m3/PMH0 to 48.9 m3/PMH0 in different regions. This article provides key recommendations on improving motor-manual felling productivity, which can provide a guide for sustainable harvesting planning purposes. [ABSTRACT FROM AUTHOR]

Copyright of Boletín Científico Centro de Museos de Historia Natural is the property of Universidad de Caldas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to model the height of trees and volumetric production of eucalypts trees on the agrosilvopastoral systems (AGP) of Zona da Mata Mineira region, Brazil, using artificial neural network (ANN) and regression models to determine the best alternative. The data was obtained from five systems with different spatial arrangements (8 × 3 m, 10 × 3 m, 11 × 3 m, 12 × 3 m, 12 × 2 m, and 12 × 4 m), ages (5.5, 6.5 and 8 years) and genotypes, of which 122 sample trees were scaled. Hypsometric and volumetric models were adjusted considering no stratification or stratification by the AGP, spatial arrangement, and genotype. A multilayer perceptron ANN was trained using resilient propagation and skip layer training algorithms. The stratification variables used in the regression were used in the ANN as categorical variables. To estimate height of trees were used as continuous variables: diameter at breast height (dbh), dominant height (Dh), and age. To estimate volume were used as continuous variables: dbh, total height, and age. The AGPs's mean annual increment at 5.5, 6.5 and 8 years of age ranged from 21 to 62 m3 ha−1 year−1. ANN was proven to be an efficient methodology for hypsometric and volumetric estimates of eucalypt in AGP in the study region. [ABSTRACT FROM AUTHOR]

Abstract The aim of this study was to develop a general applicability equation to represent the hypsometric relationship of Eucalyptus benthamii Maiden et Cambage stands in Irani, Santa Catarina. The data came from a continuous forest inventory, with a simple random sampling design and the Bitterlich method. The functions to represent the hypsometric relationship were adjusted with their parameters linear function of stands variables, based on the Gauss-Newton algorithm. The models were evaluated according to the criteria of adjustment and precision, accuracy and validation. In general, the Harrison model, adjusted with the coefficient “c” linear function of age, dominant diameter and basal area, presented the best statistical performance to represent the hypsometric relationship of Eucalyptus benthamii.

ABSTRACT Eucalyptus cloeziana is one of the highest-density wood species offering significant added value, frequently used in the construction and furniture industries. Despite its suitability, it may be overlooked on account of its propagation difficulties due either to its low rooting cutting capacity or to its seeds having a low germination rate perhaps attributable to the high proportion of indistinguishable impurities within the seed lots. This study aimed to develop an efficient technique for Eucalyptus cloeziana seed processing to increase the physical purity and, consequently, the physiological quality of the seed lot. Three seed lots, separated by size in sieves with 1.18, 1.00, and 0.84 mm square openings, were used. X-ray analyses were carried out, the number of normal seedlings and germination rate identified and the percentage and speed of seedling emergence under greenhouse conditions ascertained. The greenhouse evaluation showed that the seed retained in the 1.18 mm sieve presented viability and vigor twice that of the control. Therefore, the processing technique by size classification is efficient in terms of improving the physical and physiological performance of Eucalyptus cloeziana seed lots.

Forest Red Gum eucalypt provides a versatile wood and is converted into different purposes. However, such wood is somewhat limited in structural ends, which highlights the need to exploit this gap through diffusion of mechanical properties of such timber. Obtained results should assist engineers and architects in decision-making for its best building application. This paper studied two physical and fourteen mechanical properties evaluation of Eucalyptus tereticornis at two different moisture contents, following the prescriptions of Brazilian (ABNT NBR 7190: 1997) and North American (ASTM D-143-14: 2014) standard documents. Thus, 1091 repeats were carried out for all properties. By a moisture reduction from 30% to 12%, the bulk density and eleven strength properties statistically showed changes such as modulus of rupture (static bending, parallel and perpendicular compressions), modulus of elasticity (perpendicular compression and static bending), shear stress, tangential cleavage, and parallel and perpendicular hardnesses. Then, the Eucalyptus tereticornis timber could be better usable if is further applied for structural construction uses.

Leaf biochemical traits indicating early symptoms of plant stress can be assessed using imaging spectroscopy combined with radiative transfer modelling (RTM). In this study, we assessed the potential applicability of the leaf radiative transfer model Fluspect-Cx to simulate optical properties and estimate leaf biochemical traits through inversion of two native Australian eucalypt species: Eucalyptus dalrympleana and E. delegetensis. The comparison of measured and simulated optical properties revealed the necessity to recalibrate the refractive index and specific absorption coefficients of the eucalypt leaves’ biochemical constituents. Subsequent validation of the modified Fluspect-Cx showed a closer agreement with the spectral measurements. The average root mean square error (RMSE) of reflectance, transmittance and absorptance values within the wavelength interval of 450–1600 nm was smaller than 1%. We compared the performance of both the original and recalibrated Fluspect-Cx versions through inversions aiming to simultaneously retrieve all model inputs from leaf optical properties with and without prior information. The inversion of recalibrated Fluspect-Cx constrained by laboratory-based measurements produced a superior accuracy in estimations of leaf water content (RMSE = 0.0013 cm, NRMSE = 6.55%) and dry matter content (RMSE = 0.0036 g·cm−2, NRMSE = 21.28%). The estimation accuracies of chlorophyll content (RMSE = 8.46 µg·cm−2, NRMSE = 24.73%), carotenoid content (RMSE = 3.83 µg·cm−2, NRMSE = 30.82%) and anthocyanin content (RMSE = 1.69 µg·cm−2, NRMSE = 37.12%) were only marginally better than for the inversion without any constraints. Additionally, we investigated the possibility to substitute the prior information derived in the laboratory by non-destructive reflectance-based spectral indices sensitive to the retrieved biochemical traits, resulting in the most accurate estimation of carotenoid content (RMSE = 3.65 µg·cm−2, NRMSE = 29%). Future coupling of the recalibrated Fluspect with a forest canopy RTM is expected to facilitate retrieval of biophysical traits from spectral air/space-borne image data, allowing for assessing the actual physiological status and health of eucalypt forest canopies.

ABSTRACT Over the years, the species of eucalyptus has become a multipurpose raw material. In addition, the most relevant aspect of the use for various purposes is related to the production of a high quality wood, coming from short duration plantations, which is fundamental to the current demand of the industries. However, its use in civil construction has not yet reached a level of importance, due to the low knowledge of many of its resistance properties and the consequent popular fear in the use of reforestation woods, in particular the Eucalyptus grandis. This research investigated its main mechanical properties, aiming to reinforce its constructive applications in wood structures. For this, two physical properties and fourteen mechanical properties, in two different moisture conditions of the samples were evaluated, according to the norm NBR 7190 (1997). In the first moisture content, the samples were stabilized at 30%, while the second level considered the content of 12%. It was obtained 3580 determinations for the sixteen properties. From the 14 mechanical properties, only 7 had significant increases with the moisture reduction (30% to 12%), consisting of the rupture modulus in the parallel and normal compressions, normal traction and static bending; modulus of elasticity in normal compression and static bending and in shear strength.

Abstract Woody debris plays an important role in many ecosystem functions, including nutrient and carbon cycling, providing substrates for plant recruitment and habitat for fauna. Fires can affect woody debris stocks, through generating new pieces by killing or severing plant parts and consuming pre‐existing woody debris. We develop a model of woody debris dynamics with variation in time since fire and prior fire interval applicable to obligate‐seeder forests and woodlands, considering down woody debris and standing dead trees as discrete components. We then test predictions of change in woody debris derived from this model in Eucalyptus salubris woodlands in South‐Western Australia, using a multi‐century chronosequence with recent fires varying between having short (50 yr, but often much longer) prior intervals. As per our woody debris dynamics model, most attributes measured were affected by time since fire, prior fire interval, or their interaction. Woody debris biomass was greatest shortly after fire, reflecting high quantities of standing dead trees resulting from stand‐replacement disturbance. Standing dead tree density and biomass then declined with increasing time since fire, but individual dead tree size was high beyond 200 yr since fire. Down woody debris biomass remained relatively stable with time since fire, but piece size increased. Dimensions of woody debris were strongly influenced by prior fire interval, with long prior intervals resulting in pieces at least twice the size than those occurring after short prior intervals. Fire management to maximize the availability of large woody debris pieces for fauna should aim to minimize short fire intervals, while from a carbon management perspective, all fires in obligate‐seeder forests and woodlands set in train large and prolonged emissions of carbon.

Genomic selection models were investigated to predict several complex traits in breeding populations of Zea mays L. and Eucalyptus globulus Labill. For this, the following methods of Machine Learning (ML) were implemented: (i) Deep Learning (DL) and (ii) Bayesian Regularized Neural Network (BRNN) both in combination with different hyperparameters. These ML methods were also compared with Genomic Best Linear Unbiased Prediction (GBLUP) and different Bayesian regression models [Bayes A, Bayes B, Bayes Cπ, Bayesian Ridge Regression, Bayesian LASSO, and Reproducing Kernel Hilbert Space (RKHS)]. DL models, using Rectified Linear Units (as the activation function), had higher predictive ability values, which varied from 0.27 (pilodyn penetration of 6 years old eucalypt trees) to 0.78 (flowering-related traits of maize). Moreover, the larger mini-batch size (100%) had a significantly higher predictive ability for wood-related traits than the smaller mini-batch size (10%). On the other hand, in the BRNN method, the architectures of one and two layers that used only the pureline function showed better results of prediction, with values ranging from 0.21 (pilodyn penetration) to 0.71 (flowering traits). A significant increase in the prediction ability was observed for DL in comparison with other methods of genomic prediction (Bayesian alphabet models, GBLUP, RKHS, and BRNN). Another important finding was the usefulness of DL models (through an iterative algorithm) as an SNP detection strategy for genome-wide association studies. The results of this study confirm the importance of DL for genome-wide analyses and crop/tree improvement strategies, which holds promise for accelerating breeding progress. [ABSTRACT FROM AUTHOR]

The concept that vegetation structure (and faunal habitat) develops predictably with time since fire has been central to understanding the relationship between fire and fauna. However, because plants regenerate after fire in different ways (e.g. resprouting from above‐ground stems vs. underground lignotubers), use of simple categories based on time since fire might not adequately represent post‐fire habitat development in all ecosystems. We tested the hypothesis that the post‐fire development of faunal habitat structure differs between ecosystems, depending on fire regeneration traits of the dominant canopy trees. We measured 12 habitat components at sites in foothill forests (n = 38), heathy woodlands (n = 38) and mallee woodlands (n = 98) in Victoria, Australia, and used generalised additive models to predict changes in each variable with time since fire. A greater percentage of faunal habitat variables responded significantly to time since fire in mallee woodlands, where fires typically are stand‐replacing, than in foothill forests and heathy woodlands, where canopy tree stems generally persist through fire. In the ecosystem with the highest proportion of epicormic resprouters (foothill forests), only ground cover and understorey vegetation responded significantly to time since fire, compared with all but one variable in the ecosystem dominated by basal resprouters (mallee woodlands). These differences between ecosystems in the post‐fire development of key habitat components suggest there may also be fundamental differences in the role of fire in shaping the distribution of fauna. If so, this challenges the way in which many fire‐prone ecosystems currently are categorised and managed, especially the level of dependence on time since fire and other temporal surrogates such as age‐classes and successional states. Where time since fire is a poor surrogate for habitat structural development, additional complexity (e.g. fire severity, topography and prior land‐use history) could better capture processes that determine faunal occurrence in fire‐prone ecosystems. [ABSTRACT FROM AUTHOR]

Ralstonia solanacearum sensu lato causes bacterial wilt in many agronomic crops and tree species economically important worldwide. It is a species complex that has been divided into phylotypes and sequevars, commonly related to geographic distribution. Knowledge of the phylotype composition and genetic variability in populations of this phytopathogenic bacterium is useful for implementing effective control measures. In a survey conducted in 2019, six bacterial strains were obtained from wilted Eucalyptus urophylla trees in plantations located in the municipality of Dom Eliseu, Pará state, Brazil. Multiplex PCR based on the internal transcribed spacer (ITS) indicated that the bacterial strains belonged to two different species, namely R. pseudosolanacearum (phylotype I) and R. solanacearum (phylotype II). In a phylogenetic analysis, the nucleotide sequence of the endoglucanase (egl) gene from eucalypt strains of phylotype I clustered together with sequevar 18 sequences from GenBank. Separation of the strains into two different species was confirmed by repetitive element palindromic PCR (rep‐PCR). Pathogenicity tests demonstrated that the R. solanacearum and R. pseudosolanacearum strains recovered from E. urophylla cause disease in both tomato and eucalypt plants. Until now, only R. solanacearum (Phylotype II) has been reported causing wilt symptoms on Eucalyptus spp. in Brazil. Therefore, the presence of R. pseudosolanacearum and a need for better understanding of its genetic and aggressiveness variability as well as possible differences between the two species should be considered in breeding programmes aimed at the deployment of host resistance. [ABSTRACT FROM AUTHOR]

Copyright of Silva Lusitana is the property of Unidade de Investigacao de Silvicultura e Productos Florestais and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Grey mould, caused by the fungus Botrytis cinerea, is one of the diseases that occur in seedlings of Eucalyptus dunnii. The control of this disease is carried out mainly with chemical fungicides, but such use should be restricted to cases of high severity. An interesting alternative is the biocontrol using endophytic microorganisms. We assessed the antagonistic potential of endophytic yeasts from coffee beans against B. cinerea in vitro and their potential for biocontrol of grey mould in detached leaves and three-month-old seedlings of E. dunnii. Ten strains significantly inhibited the growth of B. cinerea in vitro (59.9–86.9%), and Wickerhamomyces anomalus showed the highest inhibition of the pathogen. In the in vivo assays, W. anomalus remained viable for 10 days after spraying on leaves and reduced the severity of the grey mould in E. dunnii detached leaves and seedlings. The results were statistically similar to those obtained with chemical fungicide when sprayed weekly. This is the first report of the effectiveness of endophytic W. anomalus as a suppressor of the development of grey mould in E. dunnii. [ABSTRACT FROM AUTHOR]

In Brazil, most Eucalyptus plantations are located in regions experiencing periods of water shortage where fertilizers are intensively used to achieve high productivity. Fertilization can affect water use. However, the effects of fertilization on tree growth patterns during extreme droughts periods remain unknown. A throughfall exclusion experiment was set up in São Paulo State-Brazil to study the effects of potassium (K) and sodium (Na) fertilization and their interaction with water supply in the growth of Eucalyptus grandis trees over an abnormal season of 6 months of extreme drought in comparison with that in normal seasons, as well as the differences in responsiveness to intra-annual meteorological variability. Arranged in a split-plot design, the factors were water supply (37% throughfall exclusion vs. no throughfall exclusion) and fertilization regime (K, Na, and control). Basal area growth was monitored by band dendrometers measurements at 14-day intervals over 2 years. Meteorological and soil water content data were also collected. K and Na fertilization increased the tree basal area by four and three-fold, respectively, during normal seasons. During a severe drought season, these positive effects were suppressed. However, K- and Na-fertilized trees achieved a similar cumulative basal area increment to that of the control trees. The 37% throughfall exclusion significantly decreased tree growth in all treatments only in the severe drought period, and these effects were stronger in K-fertilized trees. K-fertilized trees were highly responsive to intra-annual meteorological variability. Our results suggest that extreme drought has similar effects on E. grandis tree growth regardless of the K/Na fertilization regime. [ABSTRACT FROM AUTHOR]

Antioxidants have a crucial role in protecting the body from oxidative stress, which would otherwise result in cellular damage and possibly predispose animals to disease. The antioxidant capacity of koalas (Phascolarctos cinereus) and its association with health or disease status is currently unknown. Ascorbate, a dietary antioxidant, has previously been identified in a few eucalypt species eaten by koalas. This study aimed to determine 1) differences between the antioxidant capacity of healthy and diseased koalas, and 2) concentration of the antioxidant ascorbate in Eucalyptus spp. leaves eaten by koalas. To determine differences in antioxidant capacity of koalas, plasma samples from clinically healthy koalas in Kangaroo Island, South Australia (SA) (n = 23), euthanized koalas with oxalate nephrosis from Mount Lofty Ranges, SA (n = 11), and euthanized koalas with chlamydiosis from Moggill, Queensland (n = 11) were analyzed for the three antioxidants α-tocopherol, ascorbate, and retinol and for two measures of antioxidant capacity, ferric reducing ability of plasma (FRAP), and trolox equivalent antioxidant capacity (TEAC). The thiobarbituric acid reactive substance (TBARS) measured formation of oxidants, and an oxidative stress index (OSI) was calculated by TBARS/(TEAC + FRAP). Ascorbate concentration was measured in dietary eucalypt leaves from Mount Lofty Ranges and Moggill. Results showed that in diseased Mount Lofty Ranges and Moggill koalas, plasma α-tocopherol concentrations were significantly lower, and ascorbate, TBARS, and OSI was significantly higher compared with clinically healthy koalas from Kangaroo Island. Ascorbate was high in eucalypt leaves, particularly young leaves from the Mount Lofty Ranges. This study showed that disease was associated with some measures of poor antioxidant capacity in koalas and also found that ascorbate is high in the dietary eucalypts of koalas. [ABSTRACT FROM AUTHOR]

Understanding the effect of planting densities and species proportions on light absorption and light use efficiency can help to improve the management of mixed-species forest plantations. Our study aimed to disentangle the role of light interception and light use efficiency (LUE) on the biomass production of Eucalyptus grandis (E), a highly productive species in tropical conditions, and Acacia mangium (A), a N 2 -fixing species, in monocultures and mixed-species plantations for contrasting planting densities. A randomized block experiment set up over 4 ha in southern Brazil was intensively monitored for 14 months at mid rotation. The absorbed photosynthetically active radiation (APAR) was simulated for each tree of the experiment using the tri-dimensional MAESPA model parameterized with detailed in situ measurements of tree and foliage. LUE for stem wood production was estimated as the ratio of measured stem biomass production (SBP) and simulated APAR. The APAR of Eucalyptus trees did not significantly differ between monocultures and mixed plantations, the reduction of Eucalyptus density being compensated by an increase in light absorption of Eucalyptus individuals. The LUE of Eucalyptus trees in monoculture and mixed-species stands was found to be comparable only at low planting densities. The replacement of Eucalyptus trees with Acacia trees resulted in a reduction in Eucalyptus LUE only at high planting density. The SBP of Eucalyptus trees was mainly explained by differences in APAR, while both APAR and LUE explained the SBP of Acacia trees. The maximum stand production was obtained with monoculture of Eucalyptus at high density and no mixture reached this productivity. Reducing the proportion of Eucalyptus in mixture lead to a substantial decrease in stand production at high planting density due to a decrease in LUE, while this stand production reduction was offset at low planting density, underlying a higher diversity effect at low planting density. In the perspective of increasing diversity in forest plantations to foster multifunctionality, mixed plantations of Acacia and Eucalyptus at low planting density can be an interesting option to maintain a relatively high productivity, which is similar to Eucalyptus monocultures at the same low planting density. • APAR, wood growth and LUE were estimated in monocultures and mixed-species plantations. • These variables were analysed in function of the species proportion and planting densities. • The maximum stand production was for Eucalyptus monoculture at highest density. • At the low tree density in a mixed-species stand, Eucalyptus had similar productivity to that in pure than Eucalyptus at low density". [ABSTRACT FROM AUTHOR]

• We identified 76 studies of nest boxes and birds in commercially managed forests. • There is growing evidence that nest boxes benefit birds in commercially managed forests. • Most studies explore insectivores in pine forests of the Northern Hemisphere. Nest boxes are widely used to supplement natural tree cavities used by fauna, particularly in "working lands" where large, old trees are cleared or harvested. Commercially managed forests comprise large areas of global forest cover and nest boxes provide an opportunity to encourage biodiversity in areas where trees are harvested before natural cavities form. Here, we used a systematic review to provide a global overview of the scientific literature on nest boxes and bird conservation within commercially managed forests. Our systematic review identified 76 studies exploring the influence of nest boxes on birds in commercially managed forests, ranging from studies of individual birds to whole communities. Insectivorous birds were the most common reported users of nest boxes, and studies that incorporate a before and after period provide one line of evidence that nest boxes enhance bird occupancy and survival. However, only a small number of bird species have been observed using nest boxes and most studies were conducted within pine-dominated forests in Europe and North America. We recommend future research to develop knowledge of a wider range of bird taxa and commercially managed forest types. Further, we advocate for testing different types of nest box designs, materials, and spatial arrangements to improve conservation outcomes. This will help to ensure nest boxes, in combination with ecological restoration and a suite of other conservation actions, enhance biodiversity and the ecosystem functions provided by birds, such as pest control. [ABSTRACT FROM AUTHOR]

O presente trabalho teve como objetivo analisar o crescimento e taxa de sobrevivência de um plantio florestal experimental com quatro espécies do gênero Eucalyptus, E. dunnii, E. benthamii, E. cloesiana e E. saligna, na cidade de Canoinhas – SC. O talhão florestal contém 10 linhas com 25 árvores cada, a um espaçamento 3 m x 3 m em área de 2.250 m2 com idade de 5 anos. O censo florestal foi realizado com trena e fita métrica para a medição do diâmetro e hipsômetro para a medição em altura. As medições foram realizadas nos anos de 2012, 2013, 2014, 2015 e 2016. Foram calculados a taxa de sobrevivência, o Incremento Médio Anual – IMA e o Incremento Corrente Anual – ICA ao longo dos anos. Também foram avaliadas a distribuição diamétrica e a altura média para cada espécie. Os melhores IMAs foram de E. benthamii, E. dunnii e E. saligna, respectivamente 46,21, 42,87 e 40,77 m3 .ha-1.ano-1. A espécie com o pior desempenho foi E. cloesiana com 12,24 m3 .ha-1.ano-1. As espécies E. benthamii, E. dunnii e E. saligna atingiram a idade técnica de corte. As taxas de sobrevivência foram de 96% para E. dunniii, 94% para E. saligna, 82% para E. benthamii e 80% para E. cloesiana. Os resultados permitem dizer que a espécie E. cloesiana é a menos adaptada para o clima do local de estudo, com baixa taxa de sobrevivência e menor crescimento. The present work aimed to analize the growth and survival rate of an experimental forest plantation with four species of the genera Eucalyptus, E. dunnii, E. benthamii, E. cloesiana and E. saligna, in the city of Canoinhas – SC. The forest area contains 10 lines with 25 trees each, at a spacing of 3 m x 3 m with an area of 2,250 m2 and five years old. The forest census was carried out with measuring tape for diameter measurement and hypsometer for height measurement. Measurements were made in 2012, 2013, 2014, 2015 and 2016. The survival rate, the Mean Annual Increment – MAI and the Periodic Annual Increment – PAI over the years were calculated. The diameter distribution and mean height for each species were also evaluated. The best MAIs were E. benthamii, E. dunnii and E. saligna, respectively 46.21, 42.87 and 40.77 m3 .ha-1.year-1. The species with the worst performance was E. cloesiana with 12.24 m3 .ha-1.year-1. The species E. benthamii, E. dunnii and E. saligna reached the technical cutting age. The survival rates were 96% for E. dunniii, 94% for E. saligna, 82% for E. benthamii and 80% for E. cloesiana. The results suggest that the E. cloesiana species is less adapted to the climate of the study site, with a lower survival rate and lower growth.

The leaf composition has been used as a tool in establishing the nutritional diagnosis and evaluation of the effectiveness of the use of nutrients. This knowledge is still scarce in subtropical conditions of cultivation. In this sense, the study aims to evaluate the effect of N, P and K fertilization on leaf concentration of Eucalyptus urograndis. The experiments were installed in the Oxisols of the sandy-loam texture, in the counties of Jaguariaíva and Ventania, state of Paraná. In the N and P experiments, the following doses: 0; 30; 60; 120 and 240 kg ha-1 of N and P2O5; and 0; 35; 70; 140 and 280 kg ha-1 K2O, split in four applications: during planting and side dressing at 3, 9 and 12 months of age. The response was evaluated according to the nutritional status of the plants at 12, 24 and 36 months, by foliar concentration. It also evaluated levels of K deficiency plant through visual and chemical analysis. The application of N and P did not result in alteration in the leaf contents of the same in all evaluated periods and in the two regions, with a slight decrease in the concentrations with time. A different effect occurred with K at the Jaguariaíva site, which altered its foliar concentration at the 24th and 36th month, and increased foliar concentrations with time. These effects demonstrate that foliar diagnosis, through foliar concentrations, may present limitations of interpretation and should not be evaluated separately for fertilization recommendation. [ABSTRACT FROM AUTHOR]

Cryptococcosis is a fungal infection caused by members of the Cryptococcus gattii and C. neoformans species complexes. The C. gattii species complex has a strong environmental association with eucalypt hollows (particularly Eucalyptus camaldulensis), which may present a source of infection. It remains unclear whether a specific mycobiome is required to support its environmental survival and growth. Conventional detection of environmental Cryptococcus spp. involves culture on differential media, such as Guizotia abyssinica seed agar. Next‐generation sequencing (NGS)‐based culture‐independent identification aids in contextualising these species in the environmental mycobiome. Samples from 23 Australian tree hollows were subjected to both culture‐ and amplicon‐based metagenomic analysis to characterize the mycobiome and assess relationships between Cryptococcus spp. and other fungal taxa. The most abundant genera detected were Coniochaeta, Aspergillus, and Penicillium, all being commonly isolated from decaying wood. There was no correlation between the presence of Cryptococcus spp. in a tree hollow and the presence of any other fungal genus. Some differences in the abundance of numerous taxa were noted in a differential heat tree comparing samples with or without Cryptococcus‐NGS reads. The study expanded the known environmental niche of the C. gattii and C. neoformans species complexes in Australia with detections from a further five tree species. Discrepancies between the detection of Cryptococcus spp. using culture or NGS suggest that neither is superior per se and that, rather, these methodologies are complementary. The inherent biases of amplicon‐based metagenomics require cautious interpretation of data through consideration of its biological relevance. [ABSTRACT FROM AUTHOR]

Summary: Reasons for variable establishment of Jarrah (Eucalyptus marginata D. Don ex Sm.) and Marri (Corymbia calophylla (Lindl). K. D. Hill & L. A. S. Johnson) on restored forest sites after bauxite mining in south‐west Australia are not well understood. To refine restoration outcomes, we compiled tree seedling density establishment data from surveys of 654 previously mined sites restored between 1998 and 2017, and applied generalised linear models to discriminate the effects of 24 climatic and restoration practice variables. Final models explained 50% and 31% of the variation in Jarrah and Marri density, respectively. Broadcast seeding and fertiliser rates were positively related to seedling density. A more even rainfall distribution in the early wet season increased seedling density. However, persistent rain later in the wet season decreased density, possibly as a result of ripline soil saturation or ponding. Higher average daily maximum temperatures in the dry season decreased seedling density probably due to drought stress, but warmer daily temperature minima in both wet and dry seasons increased density. Seed rain from surrounding unmined forest was implicated as a significant, but highly variable, source of additional seed to restored sites. Restoration practices that influence soil moisture relations (tillage, depth and texture of returned soil), shallow burial of applied seed and timing of fertiliser application are likely to be important in refining restoration outcomes. [ABSTRACT FROM AUTHOR]

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Summary: Terpenoid‐based essential oils are economically important commodities, yet beyond their biosynthetic pathways, little is known about the genetic architecture of terpene oil yield from plants. Transport, storage, evaporative loss, transcriptional regulation and precursor competition may be important contributors to this complex trait.Here, we associate 2.39 million single nucleotide polymorphisms derived from shallow whole‐genome sequencing of 468 Eucalyptus polybractea individuals with 12 traits related to the overall terpene yield, eight direct measures of terpene concentration and four biomass‐related traits.Our results show that in addition to terpene biosynthesis, development of secretory cavities, where terpenes are both synthesized and stored, and transport of terpenes were important components of terpene yield. For sesquiterpene concentrations, the availability of precursors in the cytosol was important. Candidate terpene synthase genes for the production of 1,8‐cineole and α‐pinene, and β‐pinene (which comprised > 80% of the total terpenes) were functionally characterized as a 1,8‐cineole synthase and a β/α‐pinene synthase.Our results provide novel insights into the genomic architecture of terpene yield and we provide candidate genes for breeding or engineering of crops for biofuels or the production of industrially valuable terpenes. [ABSTRACT FROM AUTHOR]

An environmental history is presented from Girraween Lagoon, Darwin region of the Northern Territory, Australia. Pollen and charcoal analysis of a 5-meter sediment core provides a record of vegetation change, fire history and climate spanning 12,700 cal BP to the present day. This study focusses on tree-grass vegetation dynamics, eucalypt to non-eucalypt plant interactions, and climate–fire–human relationships in an area where few long-term savanna records exist. The dataset suggests wetlands experienced alternating episodes of ephemeral waterlogging and seasonal inundation due to post-glacial monsoon variability up until permanent inundation from approximately 6000 cal BP. The surrounding catchment transformed from a terminal Pleistocene–early Holocene wooded-savanna to a later Holocene open forest. This increase in woody cover was a prominent site feature, primarily driven by climate–moisture availability. In turn, the extent of fire and fire impact, is a function of climate–vegetation feedbacks. Such interplay between fire history, climate change and vegetation pattern was also influenced by more intense human management of the area, in the last 4000 years of the record. It is proposed Girraween may have become a much-socialized and managed human landscape in this late Holocene phase. Results provide essential baseline data describing savanna dynamics linked to contemporary ecological observation, understanding and management goals, and serves as an important resource for the Quaternary sciences and archeology of northern Australia. • Paleoecological insight in an area where few long-term savanna records exist. • Increase in Holocene woody cover a prominent site feature. • Moisture has been the primary driver of Holocene vegetation dynamics. • Extent of fire and fire impact, is a characteristic of climate and resultant vegetation. • Lagoon forms an important human freshwater source during variable Holocene climate. [ABSTRACT FROM AUTHOR]

• The new tri-PRI tracks leaf-level xanthophyll epoxidation state dynamics in a mature eucalypt forest. • Indices using two-bands do not perform well. • The new formulation is robust to constitutive pigment pool size effects across the canopy profile. • tri-PRI achieved results comparable to PLSR and continuum removal using full spectrum data. Plants actively regulate excess absorbed energy to protect photosynthetic machinery through heat dissipation in a process known as non-photochemical quenching (NPQ), a process useful for quantifying plant health and productivity. NPQ can be indirectly measured in the visible wavelengths between 500 nm and 560 nm, most commonly through the Photochemical Reflectance Index (PRI). However, there remains a lack of consensus regarding the optimal functional form and band selection to calculate PRI for the purpose of measuring NPQ mechanisms. Here, we quantitatively evaluate the effectiveness of leaf-level parametric and non-parametric spectral formulations, band locations, and number of bands to track the xanthophyll pigment cycle in a tall mature Eucalypt forest. Subsequently, our recommended approach is the new 'tri-PRI' index robust to constitutive pigment pool sizes across the canopy profile. tri-PRI is a Triangular Vegetation Index (TVI) (tri-PRI = 0.5[(520 - 490)(R 545nm - R 490nm) - (545 – 490)(R 520nm - R 490nm)]) using three reflectance bands around 490 nm, 520 nm and 545 nm, and has a physiological photosynthetic basis. We found that tri-PRI significantly outperformed PRI and other two band combinations for quantifying the xanthophyll EPoxidation State 'EPS' (tri-PRI R2 = 0.75 versus PRI R2 = 0.23), as well as the Φ NPQ and Φ PSII active chlorophyll fluorescence quenching yields. The new band placement enhanced the dynamic EPS absorption peak, while the third band provided an additional normalisation to minimise the confounding effects of pigments with overlapping spectral features. tri-PRI also performed comparably to parametric and non-parametric hyperspectral techniques and formulations using continuous spectral regions, highlighting the utility of targeted multispectral indices over hyperspectral approaches. This leaf-level study represents a foundational step toward indirectly measuring dynamic photosynthetic activity across the canopy profile in a tall mature Eucalypt forest to inform upscaling efforts from above-canopy remote sensing platforms. The application of tri-PRI and other top-performing multi-band TVI formulations for predicting EPS presented here should be explored across different canopy types, temporal-, and spatial scales. [ABSTRACT FROM AUTHOR]

In the present study, the variation of green moisture content and basic density in Eucalyptus nitens trees with sawable dimensions were examined, coming from a plantation of 18 year old, grown at the Biobío region, Chile. Nine trees were randomly selected. From each tree a set of 8 discs were obtained, which represented the following fixed heights: 0,8 m; 3,2 m; 7,0 m; 9,4 m; 15,0 m; 17,4 m; 23,2 m; and 25,6 m. From each disk samples were obtained at 10, 30, 50, 70 and 90% of the radius, in the North and South cardinal exposures, for the determinations of green moisture content and basic density. The cardinal exposure in the stem was relevant for the green moisture content, but not for the basic density. Significant changes were reported in green moisture content and basic density, with the radial and axial position in the stem. Different patterns of radial variation, of green moisture content and basic density, were found along stem of the tree. The radial changes (in green moisture content and basic density were minors in the upper part of the stem, and the axial changes were minors near to the bark. [ABSTRACT FROM AUTHOR]

Calonectria leaf blight, caused by Calonectria pteridis, is currently one of the main foliar diseases in eucalypt plantations in Brazil. In warm and high rainfall regions, the disease can be a limiting factor for eucalypt production when planting susceptible genotypes. The most effective method for controlling this disease in the field is the use of resistant genotypes, which requires knowledge of the genetic variability and aggressiveness of the pathogen population for effective deployment of plant resistance. This work evaluated the genetic diversity and aggressiveness of C. pteridis populations obtained from infected eucalypt plants in Monte Dourado (Pará state) and Imperatriz (Maranhão state), Brazil. To study the genetic diversity, 16 ISSR primers were tested, five of which amplified polymorphic, reproducible and informative bands. Thirty‐one closely related genotypes were identified from 84 isolates studied, indicating that the population has a low genetic diversity. The aggressiveness of seven isolates, selected according to geographic origin and their clustering in the ISSR‐based dendogram, was determined by inoculation of a hybrid Eucalyptus grandis × E. urophylla clone under controlled conditions. Disease severity was assessed by both measuring the percentage of plant defoliation and assigning a score according to a diagrammatic scale of symptoms. A high correlation between the two evaluation methods was observed, which revealed significant differences in aggressiveness among the isolates. The diagrammatic scale is recommended for disease evaluation because results are obtained much faster, before the occurrence of severe defoliation. No correlation between clustering in the ISSR‐based phylogenetic analysis and aggressiveness was observed. [ABSTRACT FROM AUTHOR]

In the present work, Eucalyptus nitens was thermally modified in an open (atmospheric pressure) and a closed (under pressure) reactor system. The effect of the changes of the chemical composition on the mechanical properties was investigated. Hemicelluloses, cellulose, lignin, extractives, acetic acid, formic acid, total phenols and the cellulose degree of polymerization (DP) as well as modulus of elasticity (MOE) and modulus of rupture (MOR) were measured for each modification. The results indicated that the closed system modification, particularly at high pressure, presented stronger variations on the chemical structure of the modified wood than the modifications in the open system. In both modifications, MOR showed a better correlation with the chemical changes than the MOE, especially xylose, cellulose DP, lignin and total phenols. These correlations suggest a tendency of a more brittle wood in the closed system modification at high pressure than in the modifications in the open system. Results can be used as a reference for future applications of thermally modified E. nitens wood. [ABSTRACT FROM AUTHOR]

Highlights • Subgenus Eucalyptus trees contain high foliar amounts of medicinal pinocembrin. • Some species also contain high amounts of related O - and C -methylated flavanones. • High-yielding species can be selected to establish commercial flavanone plantations. Abstract Plant-derived flavanones such as pinocembrin and related methylated forms are of interest for their potential medicinal use. Commercial sources of these compounds are limited, but some trees in genus Eucalyptus subgenus Eucalyptus (family Myrtaceae) show promise due to their high foliar flavanone content and growth rate, particularly when grown in coppice cultivation. As a first step to developing commercial Eucalyptus plantations for flavanone production, this research aimed to identify high-yielding species. Foliar flavanones were quantified in 41 species and subspecies from three major sections within the subgenus. Pinocembrin concentrations were highest in two subspecies of E. preissiana with notably high levels of 15 and 18 mg g–1 dry weight (DW). The highest concentrations of 7- O -methylpinocembrin (12 mg g–1 DW) and 5,7- O -dimethylpinocembrin (20 mg g–1 DW) were found in E. croajingolensis and E. oreades , respectively. In addition, two C -methyl flavanones were identified in Eucalyptus for the first time: 6- C -methylpinocembrin (7 mg g–1 DW) in E. megacarpa and 6,8- C -dimethylpinocembrin (6 mg g–1 DW) in E. agglomerata. In general, flavanone profiles for closely related eucalypts such as subspecies were very similar. Moreover, species fit into three distinct categories - those with high concentrations of relatively pure non-methylated pinocembrin, those with highly abundant O -methyl flavanones, or those with abundant C -methyl flavanones. Saplings of two selected species grown in a trial plot largely reflected adult tree flavanone profiles, albeit at lower levels attributed to ontogenetic effects. In conclusion, we have shown that many species of Eucalyptus are abundant sources of promising medicinal flavanones. This work will enable selection of high-yielding species and genotypes for growth-rate assessment trials and the future establishment of commercial plantations. [ABSTRACT FROM AUTHOR]

The purpose of this study was evaluating polysulfides (PS) as additives in kraft cooking of wood mixtures eucalypt (E) and pine chips (P) wood mixtures, namely: 50E/50P, 70E/30P, and 90E/10P. Bleaching (O(D/A)(EP)D) and refining of pulps were also investigated. The PS addition (1.5 or 3.0%) to the kraft cooking preserved the hemicelluloses resulting increased pulp yield and reduced H-factor. The oxygen delignification was more efficient for chip mixtures containing higher proportion of pine chips, but was not largely affected by the addition of PS. The bleach chemical consumption was not significantly influenced by PS dosage or by the wood chip mixture. The burst and tear indexes were improved by increasing the proportion of pine chips to the mixture, but an opposite effect was observed for refinability, tensile index, and opacity. The kraft-PS pulps showed increased refinability, tensile, and burst strengths in relation the standard pulps, but lower opacities. [ABSTRACT FROM AUTHOR]

Conservation management often uses information on genetic population structure to assess the importance of local provenancing for ecological restoration and reintroduction programs. For species that do not exhibit complete reproductive isolation, the estimation of population genetic parameters may be influenced by the extent of admixture. Therefore, to avoid perverse outcomes for conservation, genetically informed management strategies must determine whether hybridization between species is relevant, and the extent to which observed population genetic patterns are shaped by interspecific versus intraspecific gene flow. We used genotyping by sequencing to identify over 2,400 informative single nucleotide polymorphisms across 18 populations of Eucalyptus regnans F. Muell., a foundation tree species of montane forests in south‐eastern Australia. We used these data to determine the extent of hybridization with another species, Eucalyptus obliqua L'Hér., and investigate how admixture influences genetic diversity parameters, by estimating metrics of genetic diversity and examining population genetic structure in datasets with and without admixed individuals. We found hybrid individuals at all sites and two highly introgressed populations. Hybrid individuals were not distributed evenly across environmental gradients, with logistic regression identifying hybrids as being associated with temperature. Removal of hybrids resulted in increases in genetic differentiation (FST), expected heterozygosity, observed heterozygosity and the inbreeding coefficient, and different patterns of isolation by distance. After removal of hybrids and introgressed populations, mountain ash showed very little population genetic structure, with a small effect of isolation by distance, and very low global FST(0.03). Our study shows that, in plants, decisions around provenancing of individuals for restoration depend on knowledge of whether hybridization is influencing population genetic structure. For species in which most genetic variation is held within populations, there may be little benefit in planning conservation strategies around environmental adaptation of seed sources. The possibility for adaptive introgression may also be relevant when species regularly hybridize. [ABSTRACT FROM AUTHOR]

Highlights • One feature of the perennial lifestyle of woody plants is nutrient storage in wood and bark. • This study aimed to test whether the formation of a stem is required to make plant nutrition independent of soil conditions. • Mineral nutrition and a set of physiological parameter of E. pauciflora and P. alpestre were determined. • Formation of a stem is a necessity for long-lived plants to enable growth largely independent of soil P and N availability. Abstract We sought to elucidate if the perennial lifestyle per se , or lifeform, enhances independence of soil nutrient availability. We measured parameters of CO 2 fixation and electron transport, stomatal conductance, P and N nutrition, as well as integrative water relations (δ 13C abundance) of an overstory tree (Snow Gum; Eucalyptus pauciflora, Sieber ex Spreng.) and a perennial understory shrub (Alpine Shaggy-pea; Podolobium alpestre F. Muell.) at two Australian field sites with different soil nutrient availability, but otherwise similar environmental conditions. Snow Gums are renowned for their longevity, including the ability to re-sprout profusely after fire, while Alpine Shaggy-pea has a relatively short lifespan, and regenerates from seed after fire. Photosynthesis parameters of P. alpestre were more sensitive to soil properties than for E. pauciflora. P and N status of leaves and roots of E. pauciflora were comparable at both sites, whereas P and N status of P. alpestre reflected their availability in the soil. Differences in δ 13C abundance of the two species studied indicated the use of different water sources at both field sites. These results suggest that long-lived plants with the capability to recycle nutrients from woody tissues, can grow largely independent of soil P and N availability. [ABSTRACT FROM AUTHOR]

Highlights • N cycling was compared in Eucalyptus (100E), Acacia mangium (100A) and mixed-species plantations (50A50E). • Atmospheric N fixation in 50A50E and 100A was 250 and 400 kg N ha−1 rotation−1, respectively. • N contents in litterfall and soil N mineralization rates were 60% higher in 100A than in 100E. • Soil C and N stocks were dependent on soil texture but not influenced by tree species. Abstract Mixing N-fixing trees with eucalypts is an attractive option to improve the long-term soil N status in fast-growing plantations established in tropical soils. A randomized block design was replicated at four sites in Brazil to compare the biogeochemical cycles in mono-specific stands of Eucalyptus (100E) and Acacia mangium (100A) with mixed-species plantations in a proportion of 1:1 (50A50E). Our study aimed to assess the effects of introducing A. mangium trees in Eucalyptus plantations on atmospheric N 2 fixation, N cycling and soil organic matter stocks. Litterfall and soil N mineralization were measured over the last two years of the rotation (4–6 years after planting). Aboveground N accumulation in the trees and C and N stocks in the forest floor and in the top soil were intensively sampled at harvesting age. N 2 fixation rates were estimated using the natural abundance of 15N as well as by the difference between total N stocks in 100A and 50A50E relative to 100E (accretion method). While the 15N natural abundance method was unsuitable, the accretion method showed consistently across the four sites that atmospheric N fixation reached about 250 and 400 kg N ha−1 rotation−1 in 50A50E and 100A, respectively. Except at one site with high mortality, N contents within trees at harvesting were approximately 40% higher in 100A than in 100E. Mean N contents in litterfall and N mineralization rates were about 60% higher in 100A than in 100E, with intermediate values in 50A50E. The amounts of N in litterfall were much more dependent on soil N mineralization rates for acacia trees than for eucalypt trees. Soil C and N stocks were dependent on soil texture but not influenced by tree species. N budgets over a 6-year rotation were enhanced by about 65 kg N ha−1 yr−1 in 100A and 40 kg N ha−1 yr−1 in 50A50E relative to monospecific eucalypt plantations. Introducing N-fixing trees in eucalypt plantations might therefore contribute to reducing the need for mineral N fertilization in the long-term. [ABSTRACT FROM AUTHOR]

Understanding intraspecific variation in the vulnerability of the xylem to hydraulic failure during drought is critical in predicting the response of forest tree species to climate change. However, few studies have assessed intraspecific variation in this trait, and a likely limitation is the large number of measurements required to generate the standard 'vulnerability curve' used to assess hydraulic failure. Here we explore an alternative approach that requires fewer measurements, and assess within species variation in leaf xylem vulnerability in Eucalyptus globulus Labill., an ecologically and economically important species with known genetic variation in drought tolerance. Using this approach we demonstrate significant phenotypic differences and evidence of plasticity among two provenances with contrasting drought tolerance. Few studies assess the range in drought tolerance that exists among individuals of the same species, yet this is critical in accurately predicting the effect of climate change on plants. This may be the result of the labour intensive process of assessing drought tolerance, which typically requires multiple measurements per individual. Here we present an alternative approach for large-scale analysis that reduces the number of measurements, thereby improving efficiency and increasing our ability to assess a broader range of individuals. [ABSTRACT FROM AUTHOR]

Abstract Epicormic and basal resprouting promote tree survival and persistence in fire-prone regions worldwide. However, little is known about limits to resprouting effectiveness when severe wildfires increase in frequency. In the extensive fire-tolerant mixed-eucalypt forests of temperate Australia, we examined the effects of one and two high-severity wildfires within six years on relationships between tree size (stem diameter) and resprouting (epicormic and/or basal), and on seedling regeneration. The diameter of eucalypts likely to be topkilled (no epicormic recovery) by high-severity fire increased from ∼15 cm after the first wildfire to ∼22 cm after the second. Middle-sized stems (22–36 cm diameter) were likely to resprout both epicormically and basally after one wildfire, but short-interval wildfires eroded this dual capacity, thereby reducing the probability of survival. Seedling abundance also decreased after two successive fires. Our study indicates that short-interval wildfires increased tree 'escape size', and eroded resprouting success particularly of middle-sized trees, which were too large for basal resprouting but too small for epicormic recovery. This, in combination with reduced seedling recruitment, portends structural and demographic challenges for even the most fire-tolerant forests under emerging fire regimes. Graphical abstract Epicormic and basal resprouting are two effective mechanisms in ensuring tree survival and persistence in fire prone regions of the globe. However, as fire regimes change, the reliability of these mechanisms may begin to be tested. In our study, we assessed the relationship between tree size and resprouting in a widespread, fire-tolerant forest type in south-eastern Australia (pictured). Here, an increase in recent fire activity resulted in the forest being burned once, and twice, in six years. We determined that trees must be of a progressively large size to effectively resist the impact of frequent fire. We also detected that both basal and epicormic resprouting likelihood decreases under frequent fire, and most surprisingly, that the most vulnerable stems under such circumstances are not the very small or large, but intermediate sized stems. Image 1 Highlights • Epicormic and basal resprouting are two effective mechanisms for trees to survive fire. • There are few observations of how epicormic and basal resprouting responds to abrupt increases in fire frequency. • Larger stems are required to resist topkill (no epicormic recovery) under frequent fire. • Frequent fire decreased the likelihood of both basal and epicormic resprouting across all stem sizes. • Frequent fire increased the risk of 'resprout failure' particularly in intermediate sized stems. [ABSTRACT FROM AUTHOR]

The history of the treatment of tuberculosis in Australia has largely been focused on the development of medical treatments, the architectural features of custom-built sanatoria and the human impact of the disease in the nineteenth and early twentieth centuries. These discussions often mention contemporary debates amongst medical men and the laity regarding the best treatment, but the influence of medical climatology in deciding where medical facilities should be placed is often overlooked. The first sanatorium in the Colony of Victoria had two branches: Echuca and Mount Macedon. These two locations differ in terms of altitude, the surrounding forest and meteorological variation. Yet, both sites were considered suitable at the time for the location of a sanatorium, possibly due to the health-promoting and aesthetic aspects of nearby eucalypt forests. This article explores why they may at first modernly appear to be substantially different locations, but contemporary medical climatology emphasised their similarities. [ABSTRACT FROM AUTHOR]

There is increasing concern about tree mortality around the world due to climatic extremes and associated shifts in pest and pathogen dynamics. Yet, empirical studies addressing the interactive effect of biotic and abiotic stress on plants are very rare. Therefore, in this study, we examined the interaction between drought stress and a canker pathogen, Quambalaria coyrecup, on the eucalypt – Corymbia calophylla (marri), which is experiencing increasing drought stress. We hypothesized that drought stress would increase marri's susceptibility to canker disease, and cankers would have the largest negative effect on plants that are already drought stressed before pathogen inoculation. To test the hypotheses, in a glasshouse, marri saplings were exposed to drought either before or after pathogen inoculation, or were well-watered or droughted throughout the experiment either with or without inoculation. Canker development was greater in well-watered saplings than in droughted saplings, with the fastest development occurring in well-watered saplings that had experienced drought stress before inoculation. Irrespective of water treatments, marri saplings employed phenol-based localized biochemical defence against the pathogen. Drought reduced photosynthesis and growth, however, a negative effect of canker disease on saplings' physiological performance was only observed in well-watered saplings. In well-watered saplings, canker-induced loss of sapwood function contributed to reduced whole-plant hydraulic conductance, photosynthesis and growth. The results provide evidence that timing of drought stress influences host physiology, and host condition influences canker disease susceptibility through differences in induced biochemical defence mechanisms. The observations highlight the importance of explicitly incorporating abiotic and biotic stress, as well as their interactions, in future studies of tree mortality in drought-prone regions worldwide. [ABSTRACT FROM AUTHOR]

Bell miner–associated dieback (BMAD) is a form of canopy decline involving bell miner (Manorina melanophrys) colonies on the eastern coast of Australia. The association can include an understorey of lantana (Lantana camara) preventing eucalypt regeneration. To date, comparatively little is known about the effects of these processes on mammal diversity and abundance. We therefore considered the effects of BMAD and lantana presence on ground mammals and insectivorous bats in four forest sites within New South Wales. These were monitored in association with a restoration project for the treatment of lantana that used glyphosate spraying to kill lantana in half of six 50 m × 50 m quadrats per site (three control and three treated). Passive bioacoustic recorders, infrared cameras and Elliott traps were used to survey understorey fauna over four consecutive nights during each season. We found a greater number of small ground-dwelling and large mammals in control areas with an intact understorey of lantana relative to areas where lantana had been treated. However, insectivorous bats were not influenced by lantana presence. Our results suggest that ground-dwelling mammals benefit from the presence of lantana, as it may provide structural complexity that reduces predation risk and/or provides a food resource. [ABSTRACT FROM AUTHOR]

Understanding the factors, or filters, that preclude the recolonization of, and population persistence in, restoration areas by fauna is important for maximizing the biodiversity benefits of restoration. We investigated filters through a long‐term study examining reptile and mammal recolonization of, and population persistence in, post‐mining restoration in the northern jarrah forest of southwestern Australia. Neither mammal community composition, nor individual mammal species, differed between unmined forest and restoration but reptile communities did and some reptile species were significantly less abundant in restoration than in unmined forest. We concluded that there were no filters to mammal recolonization and persistence but that there were both unidirectional (decreasing gradually over time) and dynamic (fluctuating over time) filters to reptile recolonization of post‐mining restoration that influenced both recolonization and population persistence of some reptile species. Low volumes of coarse woody debris appeared to be a unidirectional filter that will slow recolonization by some reptile species for decades or even centuries. Canopy cover appeared to be a dynamic filter that fluctuated over a period of >7 years and precluded population persistence of some reptile species that had already recolonized the post‐mining restoration. A dearth of studies made it difficult to generalize how widespread these filters were in restoration areas but studies of thinning and burning in natural forests suggested they were likely to be widespread. Although management techniques to reduce the effect of unidirectional and dynamic filters remain poorly developed, their development and adoption will improve the ability of restoration to facilitate fauna recolonization and persistence and better contribute towards biodiversity conservation. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • We used ALS, WorldView-2 and SAR imagery to upscale tree numbers. • ALS derived tree numbers were used for training a random forest regressor. • We upscaled tree numbers with R2 of 0.61 and normalized RMSE of 62%. • The ALS and WorldView-2 predictors were the best for estimating tree numbers. • The SAR predictors alone were unable to estimate tree numbers reliably. Abstract Detailed information on the number and density of trees is important for conservation and sustainable use of forest resources. In this respect, remote sensing technology is a reliable tool for deriving timely and fine-scale information on forest inventory attributes. However, to better predict and understand the functioning of the forest, fine-scale measures of tree number and density must be extrapolated to the forest plot or stand levels through upscaling. In this study, we compared and combined three sources of remotely sensed data, including low point density airborne laser scans (ALS), synthetic aperture radar (SAR) and very-high resolution WorldView-2 imagery to upscale the total number of trees to the plot level in a structurally complex eucalypt forest using random forest regression. We used information on number of trees previously derived from high point density ALS as training data for a random forest regressor and field inventory data for validation. Overall, our modelled estimates resulted in significant fits (p < 0.05) with goodness-of-fit (R2) of 0.61, but systematically underestimated tree numbers. The ALS predictor variables (e.g. canopy cover and height) were the best for estimating tree numbers (R2 = 0.48, nRMSE = 61%), as compared to WorldView-2 and SAR predictor variables (R2 < 0.35). Overall, the combined use of WorldView-2, ALS and SAR predictors for estimating tree numbers showed substantial improvement in R2 of up to 0.13 as compared to their individual use. Our findings demonstrate the potential of using low point density ALS, SAR and WorldView-2 imagery to upscale high point density ALS derived tree numbers at the plot level in a structurally complex eucalypt forest. [ABSTRACT FROM AUTHOR]

Non-structural carbohydrates (NSCs) are crucial to support tree resprouting after disturbances that damage the crown or stem. Epicormic resprouting (from stem) could demand more from NSC reserves than basal resprouting (following top-kill), since epicormically resprouting trees need to maintain a greater living biomass. Yet, little is known about NSC use during epicormic resprouting, particularly the relative importance of stem and below-ground NSC reserves. We compared the distribution and magnitude of NSC decreases during epicormic and basal resprouting by experimentally removing crowns or stems of 14-year-old Eucalyptus obliqua L'Hér. trees in native forest, then harvesting these trees over a 10-month period (start, sprouts emerged, sprouts expanded) to measure changes in NSC concentration and mass by organ (stem, lignotuber, roots). We hypothesized that (i) NSC depletion during resprouting is primarily due to decreases in starch rather than soluble sugars concentrations; (ii) during epicormic resprouting, stem NSC concentrations are decreased irrespective of any decreases in roots; and (iii) absolute decreases in NSC mass are greater for epicormic than basal resprouting during the leafless period due to the carbon demands associated with maintaining greater living biomass. Results confirmed our hypotheses; starch was the primary storage carbohydrate, stems were an important source of starch during epicormic resprouting and carbon demands of maintenance functions were greater for epicormic resprouting, leading to greater decreases in NSC reserves. Roots were a more important starch storage organ than the lignotuber for both epicormic and basal resprouting. The proportional decrease in starch was severe for both modes of resprouting due to a long leafless period, after which trees resprouting epicormically relied on starch reserves for longer than those resprouting basally. It remains to be seen how the timing of disturbance affects the timing and vigour of resprouting, and how long-term NSC recovery differs for epicormic and basal resprouting. [ABSTRACT FROM AUTHOR]

One-year seedlings of five species of eucalypt: E. camaldulensis, E. microtheca, E. viminalis, E. globulus and E. gunnii were treated for 14 weeks in growth season, tilting a branch to c. 60° in every successful ones. We investigated the anatomical features of stems wood after 15 days and every 2 weeks according to IAWA list of features afterwards.The results showed that tilted stems formed more tension wood in the form of gelatinous fibers than straight (untreated) ones. The formation of gelatinous fibers was considered to be closely related to tension wood formation. The formation of gelatinous fibers was considered to be closely related to tension wood formation. Excluding E. globulus, all the other species formed growth eccentricity and tension wood. Although the significant differences between the species and between different locations in the branches, there were no significant differences between the percent of tension wood among the species studied.

The objective of this work was to evaluate the initial growth and the physiological characteristics of eucalypt submitted to different managements of signalgrass. The experiment was conducted in a protected environment, using a randomized blocks design with five repetitions. The treatments were arranged in a (5 x 2) + 1 factorial design, and the first factor corresponded to the types of weed management (no control; chemical control keeping the signalgrass shoot on the soil; chemical control with removal of the signalgrass shoot; mechanical control keeping the signalgrass shoot on the soil, and mechanical control with removal of the signalgrass shoot); the second factor corresponded to the two weeds species (U. brizantha and U. decumbens) and a control relative to the eucalypt in monoculture. The eucalypt growth was not affected by the presence of the Urochloa species until 50 days after treatments (DAT). However, the coexistence of these species with eucalypt for 107 DAT reduced the collar diameter, total dry matter, and the leaf area, but did not alter the characteristics related to photosynthesis and transpiration. The control method adopted, with removal or maintenance of the signalgrass shoot, regardless of species, did not change the initial eucalypt growth. It can be concluded that the coexistence of eucalypt with Urochloa decumbens or Urochloa brizantha for 105 days reduces the eucalypt growth. However, the use of chemical or mechanical control, with or without removal of signalgrass residue, were effective methods to prevent interference of these weeds.