Locust Trees Research Articles

The Salt Lake City Asylum and Hospital, 1870–1886: Mental Illness in Early Utah

The Salt Lake City Asylum and Hospital, 1870–1886: Mental Illness in Early Utah

Effect of black locust trees on the nitrogen dynamics of black pine trees in Shonai coastal forest, Japan

Effect of black locust trees on the nitrogen dynamics of black pine trees in Shonai coastal forest, Japan

Physiological Performance and Biomass Growth of Different Black Locust Origins Growing on a Post-Mining Reclamation Site in Eastern Germany

Black Locust/Robinia can play an important role in land reclamation due to its pronounced nitrogen fixation capability, fast initial growth and relative high drought tolerance. Hence, we set up a trial to test 12 Black Locust clones and three provenances growing on sandy overburden material within the open cast lignite mine Welzow-Süd (South Brandenburg) in March 2014. Since then, biomass growth of the Black Locust trees was examined and physiological performance was studied on several occasions using chlorophyll a fluorescence and Dualex® measuring technique. Plant physiological measurements revealed differences in photosynthetic vitality (PIABS), although the PIABS values followed a similar pattern and sequences across the plot. While the genotypes Fra3 and Roy show the highest photosynthetic vitality, the clones Rog and Rob display the lowest PIABS mean values. Chlorophyll and phenol content as well as the nutrition supply of the test trees vary depending on their origin and site conditions. The annual biomass growth rate corresponds to photosynthetic vitality and both depend on weather conditions during the growing season. After six years, the growing biomass amounts to 14.7 Mg d.m. ha−1 for clone Rob and 44.8 Mg d.m. ha−1 for clone Fra3, i.e., 2.5 to 7.5 Mg d.m. ha−1 year−1. Our data demonstrate a good correlation between biophysical parameters and biomass growth. We, thus, infer that physiological measuring methods can be combined to strengthen predictions regarding the physiological performance of Black Locust origins.

Genetic diversity and core collection extraction of Robinia pseudoacacia L. germplasm resources based on phenotype, physiology, and genotyping markers

Robinia pseudoacacia L. (black locust) is a multipurpose tree species for conservation ecology, feeding and forestry industry in China. In the present study, 13 phenotypic, 3 physiological characters and 48 microsatellite markers (37 Expressed Sequence Tag microsatellites and 11 genomic SSRs) were used for genotyping the 1054 black locust trees from ex-situ collections to assess the diversity and extract a core germplasm collection. The original breeding population of Robinia pseudoacacia L. showed distinct phenotypic and physiological differences for most traits under investigation; the 15 traits (93.75%) had a coefficient of variation greater than 10% for all assessed indicators, showed the abundant phenotypic diversity. Similarly, high genetic diversity was estimated in the raw population, with an average number of different alleles (Na), Shannon’s Information Index (I), gene diversity (H), and the polymorphic information content (PIC) of 9.455, 1.357, 0.654 and 0.624 per locus, respectively. Four sub-populations were identified with weak genetic structures. Three hundred thirty-two individuals (deleted 8 duplicate individuals with two types of data) were extracted from the original population, including a core collection of phenotypic traits (24 individuals), physiological traits (14 individuals) and molecular markers (308 individuals). This was 32.07% of the 1054 trees of the original breeding population and covered seven collection forest bases. Subsequently, the study compared the genetic diversity parameters, coincidence rate of range, principal component analysis, and frequency distribution test traits for the original and core populations. No significant difference was found between them, which indicated that the core germplasm population could well represent the original population. This study provides valuable information for Robinia pseudoacacia L. germplasm management, and its established core collection may be used in future studies of genome association and breeding programs.

A framework for scaling symbiotic nitrogen fixation using the most widespread nitrogen fixer in eastern deciduous forests of the United States

Abstract Carbon uptake by the terrestrial biosphere depends on supplies of new nitrogen (N) from symbiotic N fixation, but we lack a framework for scaling fixation accurately and for predicting its response to global change. We scaled symbiotic N fixation from individual N fixers (i.e. plants that host N‐fixing bacteria), by quantifying three key parameters—the abundance of N fixers, whether they are fixing N and their N fixation rates. We apply this framework to black locust, a widespread N‐fixing tree in temperate forests of the eastern United States, and harness long‐term data from southern Appalachian forests to scale fixation from trees to the landscape and over succession. Symbiotic N fixation at the landscape scale peaked in the first decade following forest disturbance, and then declined. This pattern was due to the declining density and declining fixation rates of individual black locust trees over succession. Independent of forest succession, and coincident with chronic atmospheric N deposition, we have evidence suggesting that nodule biomass produced by black locust trees has declined by 83% over the last three decades. This difference in nodule biomass translates to a maximum fixation rate of 11 kg N ha−1 year−1 and a landscape average of 1.5 kg N ha−1 year−1 in contemporary forests. Synthesis. We find key controls on symbiotic N fixation by black locust over space and time, suggesting lower fixation rates in eastern deciduous forests than previous estimates. Our scaling framework can be applied to other N fixers to aid predictions of symbiotic N fixation and ecosystem response to global change.

What Could Arrest an Eriophyoid Mite on a Plant? The Case of Aculops allotrichus from the Black Locust Tree.

Simple SummaryFor a phytophagous arthropod, plant cues and the presence of conspecifics or heterospecifics on a plant are important sources of information about food availability and predation risk. In eriophyoid mites, which are a group of economically important plant parasites, this issue is still poorly understood. In the previous study, females of the eriophyoid Aculops allotrichus prolonged their stay on unprofitable, old black locust leaves with injured conspecifics, suggesting their specific attraction to pierced individuals. The aim of this study was to shed light on this phenomenon. The series of tests using intact and artificially injured conspecifics, heterospecifics, pollen and sand grains revealed the high specificity of cues associated with mite injury. Only the presence of conspecifics triggered female arrestment on unprofitable old leaves, and this effect was more pronounced on leaf patches with injured than with intact eriophyoids. To our best knowledge, A. allotrichus is the first described herbivore in which injured conspecifics, instead of causing an alarm to be raised, keep the foraging individuals within a risky patch. Our tests using three non-host plants also suggest that A. allotrichus presumably needs more time to identify and evaluate non-host plants than host plants.Aculops allotrichus is a vagrant eriophyoid that lives gregariously on the leaves of the black locust tree. This study demonstrated that conspecifics can have a significant impact on A. allotrichus females on unprofitable, old black locust leaves and can arrest them on those leaves. The effect was more pronounced in females that were exposed to artificially injured individuals than to intact ones. They not only prolonged their sojourn on leaf discs with pierced conspecifics, but also preferred the leaf disc halves with damaged individuals to clean ones. Aculops allotrichus is the first described herbivore in which artificially injured conspecifics, instead of causing alarm, keep the foraging individuals within a risky patch. Other objects, such as artificially injured or intact heterospecifics, pollen or sand, were irrelevant to the eriophyoid females on old leaf patches. In tests with old leaves of maple, magnolia and hard kiwi vine, the females postponed their movement from non-host leaf discs, which suggests that they may need more time to recognise and evaluate unfamiliar plants than familiar ones.

Effects of Slope Aspect and Rainfall on Belowground Deep Fine Root Traits and Aboveground Tree Height.

The vertical root distribution and rooting depth are the main belowground plant functional traits used to indicate drought resistance in arid and semiarid regions. The effects of the slope aspect on the aboveground traits are visible but not the belowground deep root traits. We aimed to investigate the fine root traits of the locust tree (Robinia pseudoacacia L.) planted on southerly and northerly aspects, and the variations in the rooting depth in regions with different rainfall, as well as assessing how deep rooting, might affect the response to drought in a loess region. We selected three study sites with different rainfall amounts, with six sampling plots at each site (three each with southerly and northerly aspects). Soil core samples were collected down to the depth where no roots were present. The locust trees tended to develop deeper fine roots rather than greater heights. The tree height and diameter were greater for locust trees on northerly aspects, whereas trees on southerly aspects had significantly deeper rooting depths. Fine root traits (root length, root area, and root dry weight density) were higher in the southerly aspect for both Changwu and Ansai, but lower in Suide. The ratio of the root front depth tree height ranged from 1.04 to 3.17, which was higher on southerly than northerly aspects, and it increased as the rainfall decreased. Locust tree growth traits (belowground fine root and aboveground tree height) were positively correlated with the mean annual rainfall. The soil moisture content of the topsoil decreased as the rainfall decreased, but the pattern varied in the deep layer. Our results suggest that the variations in the belowground rooting depth under different slope aspects may be related to plant survival strategies. The vertical extension of the rooting depth and tree height may be key functional traits that determine plant growth in drought-prone regions.

Evaluation of the Efficacy of Plant Materials for the Control of Flea Beetles Podagrica spp on Okra Abelmoschus esculentus L

The efficacy of the Senegal prickly-ash Zanthoxylum zanthoxyloides (Lam.) roots and the African locust bean tree Parkia biglobosa (Jacq.) pod back was study for their efficacy in the control of okra pest, Podagrica spp. The study was carried out in the laboratory and on the field in the farming season of 2018. Z. zanthoxyloides roots were obtained from Jima-Doko forest and P. biglibosa fruit back from Takunpara. Both plant materials were air-dried under shade for 120 hours. Both plant parts were pounded separately in wooden mortar with the aid of wooden pestle until the materials turns to fine particles. Determined weight of 100, 150, 200, 250, and 300 grams were taken for each plant materials and soaked in water for 24 hours and stirred at intervals of an hour. The mixture were then sieved with a muslin cloth and filtered with Whatman filter paper to eliminate all finest particles of varying sizes. These concentrations were applied individually on 10 adults of Podagrica spp. in the laboratory. It was observed that the concentration of 200 – 300g performed better for both plant materials in the control of okra flea beetle. These resulted to the death of above 50% of the insect within 2 hours. These significant laboratory trials were then formulated and taken to the field. Both plant materials acted as anti-feedants and repellants against Podagrica spp. It was also revealed that Z. zanthoxyloides performed significantly (p<0.05) better than the P. biglibosa. Furthermore, short interval applications (<or=3days) of these plant materials could be a good replacement for synthetic chemicals, hence bio-pesticides that could be adopted for organic agriculture.

Chorus at a Burning Cop Car

Chorus at a Burning Cop Car Yannick Giovanni Marshall (bio) Click for larger view View full resolution Virginia Chihota, Ndiri Mwana Wa. … (I am a child of ….) (2018). Serigraph on Linen Canvas, 210 × 201 cm, 82 5/8 × 79 1/8 in. [End Page 1] Chorus at a Burning Cop Car The Black Antifascist This is Basra. The mutiny of the suplexing flamethrowerengulfing the pigpen. Blowback through cruiser windowssingeing unopenable rear-doors. There is fire in your backseat.Fire where you would have imprisoned Shadrach and Meshachin pulled up belt-less jeans behind bulletproof glassand fading pre-arrest earth bodyslapped against the rear window like a mother. Now there is fire on the hood where durags squirmed like caught trout, firewhere our giants bent like oaks planted under low ceilings, firewhere the lionesses were claustrophobic in the backseat and the hell-houndspawed at the glass. Now your tire is an immolated monk,its rubber eviserated, and the Quiktrip tries to keep its soulin its aisles. There will be a rewilding. Sea-spray will soak hoodies, and black-tattooed blackskinstouch out at the sun, and the sun will allow to be touchedand will touch blackskins and glisten them like an afternoon ocean.Woodlands will be hosed down and steaming, overpopulated with ladybugsand the thugs will know them and not deli counter glass and shoutingand the inevitable darling in full shower-cap and nightgown regaliawill not hear the shot and fall on her knees nor Pietà. The fatherswill not have to wring their shirts, nor pretend to be strong,nor pretend to grieve. There is fire over your body, cop car. Not sincethe grand machine arms that strung you up like skinned cowsplacing your pieces in place laying your trunk into sparking metalhave you felt fire. And now to have your municipality stripped off your sides andyour authority sunken and your body returned to mineralsand chemicals, you are Negro-toned. I wonder if, for them, this is their '16 Jesse Washington.The QuikTrip their Francis L. McIntosh tied to the locust tree near 10th and Marketwith the rocks thrown at the cranium to melt it. I wonder if they felt the QuikTrip's fall in their sides andknew of what it might portend. That they saw 99¢ corn dogs scream for their lives and the gas threaten toblow and hugged up onto their property, kissing the top of their heads behind shut blinds. [End Page 2] God will weep for our lynching of this car. For the bulging of its seat coveringsand the crisp of the cupholders. History will close its books to us and we will have to deny itand say not to always bring up the past. And we will have to avert our eyesfrom rent-a-center security cam footage of silhouettes drawing your still beating metalfrom bushfire. The Conservative The black hordes descend in flames over you, cop car. They lick at your heels, o, you QuikTrip. They leap onto your back and beat you and drench you with kerosene and light themselves on fire. There is no justice. Only the Negroes in the trees. And the Vaudeville moon apologizing and apologizing above a black-scarved insurgency throwing Molotov cocktails into art galleries and nurseries. Where are your 'bolitionists, cop car? Who shall set you free? Are there no pickaxe swinging Delta crooners for you, o cop car. Your revolutionaries are many but none of them are poets. Q is not crouching atop a Friesian horse with arm extended to snatch our cities back by the scruff of their neck. No, you've been cordoned off, cornered, broken into and burned. You melt at the hands of the Wicked of "equality." Those who would sickle Athens into a work-camp and elect Senators smacking blackberry jam off their lips. Those who will graduate from cop cars to homes and sheltering places. You martyr, with no tombstone, no epitaph, no burial at sea, save the Darren Wilson bracelets on the wrists of your lovers waving. And the thin blue line pulled above torrents...

American tulipwood (Liriodendron tulipifera L.) as an innovative material in CLT technology

American tulipwood (Liriodendron tulipifera L.) as an innovative material in CLT technology. CLT (cross laminated timber, X-Lam) is one type of engineered wood products. The first idea of CLT was presented in the seventies of the last century. It is manufactured with timber boards placed side by side commonly with 3, 5 and 7 layers glued at 90 degrees to adjacent layer. The CLT production technology was developed for softwood. The main species in CLT production is Norway spruce (Picea abies L.) and less often White fir (Abies alba Mill.). Hardwood is also used more and more for production of CLT, most often, the wood of Silver birch (Betula pendula Roth.), Ash (Fraxinus excelsior L.), poplars (Populus spp.), Locust tree (Robinia pseudoacacia L.). This paper describes the suitability of cheap tulipwood (Liriodendron tulipifera L.) as a raw material for the production of CLT. Examples of the use of this type of panels in construction are also presented. The tulipwood has similar physical characteristics to softwood, for which CLT production technologies were previously developed. This makes it possible to use the technology previously for softwood CLT was developed. In addition, the tulipwood is characterized by aesthetic visual quality (wood surface similar to marble). Thanks to this, CLT boards to make exposed surfaces can be used.

Development and preliminary application of novel genomewide SSR markers for genetic diversity analysis of an economically important bio-control agent Platygaster robiniae (Hymenoptera: Platygastridae)

Platygaster robiniae Buhl and Duso (Hymenoptera: Platygastridae) is an egg-larvae parasitoid of the black locust gall midge (Obolodiplosis robiniae) (Haldeman) (Diptera: Cecidomyiidae) which is a serious invasive pest in China, where it attacks an important hardwood species, the black locust tree, Robini pseudoacacia L. (Fabales: Fabaceae). Despite the use of P. robiniae as an effective biocontrol agent, the absence of sequence data and other molecular markers have limited its genetic applications for pest management in forests. Simple-sequence repeats (SSRs) are valuable molecular markers for population genetic structure studies. In the present study, we identified 14,123 SSRs, of which 7799 SSR primer pairs were successfully designed. Subsequently, 240 SSR were chosen and tested with 48 P. robiniae accessions from two geographically separated populations in north and south China. Of these, 34 were polymorphic, with an average of three alleles (Na) and four genotypes (NG) each. The average values of observed heterozygosity (Ho) was 0.3514, expected heterozygosity (He) 0.4167, Shannon's information index (I) 0.7143, and polymorphism information content (PIC) 0.3558, respectively. Neighbour joining analysis (bootstrap 1000) revealed that Chengdu (CD) and Dangdong (DD) popluations clustered into two main divisions, and some individuals from two popluations clustered together as the third devision, which indicated the gene flow and genetic differentiation were present between two populations. Our finding indicates that these SSR markers will be useful for further studies on the genotype identification and genetic mapping of the genus Platygaster.

Preparation of Cellulose Nanoparticles from Foliage by Bio-Enzyme Methods

There are vast reserves of foliage in nature, which is an inexhaustible precious resource. In this study, the chemical components of five foliage types (pine needles, black locust tree leaves, bamboo leaves, elm leaves and poplar leaves) were analyzed, including cellulose content, hemicellulose content, and lignin content. The bio-enzymatic method was then used to prepare cellulose nanoparticles (CNPs) from these five kinds of leaves, and the prepared CNPs were analyzed using TEM, FTIR, FESEM, and XRD. The results showed that the content of hemicellulose in bamboo leaves was the highest, and the lignin content in the other four leaves was the highest. The cellulose content in the five kinds of foliage was arranged from large to small as pine needles (20.5%), bamboo leaves (19.5%), black locust leaves (18.0%), elm leaves (17.6%), and poplar leaves (15.5%). TEM images showed that the CNPs prepared by the five kinds of foliage reached the nanometer level in width and the micrometer level in length; therefore, the CNPs prepared in this study belonged to cellulose nanofibers (CNFs). The results of FTIR and XRD showed that CNFs prepared by the enzyme treatment exhibited a typical crystalline structure of cellulose II. The degree of crystallinity (DOC) of CNFs prepared from pine needle, poplar leaves, and bamboo leaves are 78.46%, 77.39%, and 81.51%, respectively. FESEM results showed that the CNFs prepared from pine needles, poplar leaves and bamboo leaves by enzymatic method presents a three-dimensional (3D) network structure, and their widths are 31 nm, 36 nm, and 37 nm, respectively. This study provides a meaningful reference for broadening the use of foliage types and improving their added value.

Elimination of black locust Robinia pseudoacacia L. as a non-native species in Bielański Forest (Las Bielański) in Warsaw, Poland – success or failure?

We sought to determine the outcomes of 25 years of implementation of the plan for the elimination of the black locust from Warsaw’s Bielański Forest. Forty years was the planned duration of the work to eradicate the non-native species, through the removing of individual trees from stands, repeated every 8–10 years. We presumed that the effects of these silvicultural treatments were positive if during the 1992–2017 study period, it would be possible to note declines: in density (number of individuals per hectare) of black locust trees (even as density of maple trees increased); in the abundance of saplings of the species (as opposed to maple); and in the rate of advancement of the species from the low to the ‘high sapling’ layers (again as opposed to maple). Empirical data were collected from 29 permanent sampling plots every five years. However, just 7 years into the eradication effort, 1999 brought protests from people living close to the Forest, who were left uninformed about the intention to fell black locust trees. These protests proved so effective that they resulted in an almost-complete abandonment of the relevant silvicultural measures. Thus, 25 years on, the conservation goal set for the Forest had only been achieved in part, as the decrease in density of black locust trees in the forest observed for 1992–1997 was followed by a slower process of decline that by definition reflected natural processes, rather than the now-abandoned tree-felling measures. Furthermore, black locust trees were able to continue their advance up from the ‘low sapling’ to ‘high sapling’ layers. The 1999 event thus emphasised, not only the need to secure the participation and understanding of a local community in regard to forest management; but also the requirement that people be educated about their area’s valuable natural attributes, and about the need for nature conservation measures in general.

Develop a Soil Quality Index to Study the Results of Black Locust on Soil Quality below Different Allocation Patterns

Mining areas are currently a typical ecosystem that is severely destroyed within the world. Over the years, mining activities have caused serious soil damage. Therefore, the soil restoration of abandoned mines has become a vital sustainable development strategy. The ecological environment within the hilly area of the Loess Plateau is extremely fragile, with serious soil erosion; Robinia pseudoacacia is the most popular tree species for land reclamation in mining areas within the Loess Plateau. To review the different various effects of Robinia pseudoacacia on soil quality below different configuration modes, this paper has chosen two sample plots within the southern dump of the Pingshuo mining area for comparison. The first plot is a Robinia pseudoacacia-Ulmus pumila-Ailanthus altissima broadleaf mixed forest, and the second plot is a locust tree broadleaf pure forest. The vegetation indicators and soil physical and chemical properties of the four stages in 1993, 2010, 2015, and 2020 were investigated. Principal component analysis is employed to develop the Soil Quality Index to perceive the changes within the Soil Quality Index over time. It is calculated that the Soil Quality Index of Plot I rose from 0.501 in 1993 to 0.538 in 2020, and Plot II rose from 0.501 to 0.529. The higher the SQI, the higher the reclamation of the mining area. It is found that Robinia pseudoacacia within the Robinia pseudoacacia-Ulmus pumila-Ailanthus altissima broadleaf mixed forest has higher soil quality improvement than the pure genus Robinia pseudoacacia broadleaf forest. This article can demonstrate the changes in the quality of reclaimed soil in the mining area, and can also provide a reference for the selection of reclaimed vegetation in other mining areas.

Black locust flowers as a natural source of antioxidants: Sustainable production of high-quality oil from plum by-product and its incorporation in the moisturizing cream

This study presents a challenge in terms of the development of cleaner technologies and sustainable development. The main effort was invested in the improvement of oxidative stability of plum seed oil using an eco-friendly and easy-to-use procedure (maceration). The fixed oil of plum seeds is composed of unsaturated fatty acids that are very sensitive to oxidative processes, but the addition of antioxidants can solve this problem. Since the obtained oil was further applied for the preparation of topical formulation, the aim was to avoid the use of toxic solvents and the process of their evaporation during the extraction of antioxidants from plant material. The way to overcome this problem was to directly use oil for the extraction of non-polar antioxidants from black locust flowers. The reason of use this plant material was due to its pleasant odor and high content of antioxidants. The maceration was carried out at the different temperatures (25, 40, and 60 °C) and the liquid-to-solid ratio of 10 mL/g for 48 h. After the extraction, the reducing capacity of the fixed oils was determined using a standard spectrophotometric method with Folin-Ciocalteu reagent. The extraction process was described using two kinetic models, Ponomaryov and non-stationary diffusion models. The optimal extraction time and temperature were 16 h and 60 °C, respectively, for the extraction of antioxidants. Thus obtained oil with improved stability was incorporated in the moisturizing cream to develop an innovative topical formulation that can be used against the harmful effects of the environmental factors. During the oil stabilization, the addition of synthetic antioxidants was omitted so that the application of natural antioxidants was favored. This was acceptable from an ecological point of view because in this way the planting of black locust trees will be intensified and thus the carbon dioxide emissions will be reduced. • The fixed oil of plum seeds was obtained from the industrial by-product. • The plum seed oil was enriched with antioxidants from black locust flowers. • A sustainable procedure was proposed for the improvement of oil stability. • The innovative moisturizing cream with fixed oil of plum seeds was designed.

Field Response of Green Ash (Fraxinus pennsylvanica) and Honey Locust (Gleditsia triacanthos) to Aminocyclopyrachlor1

AbstractField trials were conducted to assess the impact of aminocyclopyrachlor on green ash (Fraxinus pennsylvanica Marshall) and honey locust (Gleditsia triacanthos L.) trees in an urban environment. Aminocyclopyrachlor is a relatively new, selective, plant-growth-regulator herbicide in the pyrimidine carboxylic acid family. Treatments were applied to Kentucky bluegrass (Poa pratensis L.) sod growing with and without trees present. Evaluations included determination of a safe spraying distance from target trees and the effect of application timing on tree response. This multi-year study showed that green ash was highly tolerant to aminocyclopyrachlor while honey locust developed severe injury in trees closest to applications. Honey locust trees up to 7 m (23 ft) from the tree trunk to the edge of the application displayed moderate to severe injury symptoms and fall treatment in October and November had the lowest tree injury compared to all other application timings. Honey locust trees exhibiting moderate to severe cosmetic injury would not be acceptable to landowners; recovery over time was minimal. Trees located 13 m (43 ft) away displayed no injury for any treatment timing. Soil analysis demonstrated that aminocyclopyrachlor dissipation was the same underneath green ash and honey locust trees, and that dissipation was faster in the presence of growing trees. Taken together, these results provide a basic groundwork necessary for improving aminocyclopyrachlor labels, and a better understanding of this herbicide's effect on certain woody species.Index words: Herbicide injury, aminocyclopyrachlor, herbicide fate, tree safety.Species used in this study: Green ash, Fraxinus pennsylvanica Marshall, honey locust, Gleditsia triacanthos L.Chemicals used in this study: Aminocyclopyrachlor.

Factors involved in the biogeography of the honey locust tree (Gleditsia triacanthos) invasion at regional scale: an integrative approach

Native to the southeastern United States, the honey locust (Gleditsia triacanthos) is an invasive tree in several South American countries. Since eradication of invasive species is often costly, prevention is a better strategy. The relationship between invasive species and their habitats can be analyzed using species distribution models to produce maps of areas prone to the invasions. These maps can be used to develop efficient early detection plans of exotic species colonization. Here, we employed the Favorability Function model to assess the effects of environment and human activities on the invasive process of the honey locust in Uruguay. By integrating environmental and anthropic factors in our models, we obtained the best fitted prediction and classification indices. We showed that the southwestern region of the country concentrates the largest proportion of areas prone to the invasions. Environment was the main factor explaining the invasion of G. triacanthos, but the effect of human-related factors had a greatest effect in combination with environmental variables than on its own. We generated favorable risk maps and explanatory variables that can be used to more efficiently plan efforts to control the spread of this invasive.

Productivity of Black Locust (Robinia pseudoacacia L.) Grown on a Varying Habitats in Southeastern Poland

This study investigated growth performances of black locust (Robinia pseudoacacia L.) tree species in various soil and agro-climatic conditions in Poland. Implementing of research was based on monoculture black locust stands in which it was possible to carry out dendrometric tests allowing us to learn about their volume. These stands were located on marginal soils. In the sample plots selected for the study, the parameters of stands (main and secondary) were determined, such as number and social structure of trees, average tree height, average diameter at breast height (DBH), and volume. The volume was determined with division into trunks and branches and wood thickness classes (0.0–1.0 cm, 1.1–5.0 cm, 5.1–10.0 cm and then every 5 cm). During the research, it was found that sunlight and moisture conditions mainly affect the volume. It has been noticed that the content of nutrients in the soil plays a minor role because black locust grows very well in poorly fertile soils, often subject to erosion processes. Black locust grows well on damp, shaded slopes with northern exposures. In such areas, the stand volume was the highest (353.8 m3 ha−1), exceeding the average volume of the remaining 35-year-old stands on sandy soils by 60%. Along with the increase in the age of stands, the share of trunk wood increased with the wood of branches. The share of wood up to 5.0 cm was small in older stands, at most a dozen or so percent. However, in young stands (4- and 8-year-old), the share of the thickness class up to 5 cm was even 65% of the stand volume. In 35-year-old stands, wood fractions of 15.1–20.0 cm were dominant. In the oldest, 64-year-old stand, over 30 cm thick wood constituted 44% of the stand volume. However, statistical analysis showed, with p = 0.1644, no differences existed between the thickness of the individual thickness classes.

Crown Fractal Geometry Adapts Trees to City Life

Photo 1: Fractal-like branching architecture of a honey locust (Gleditsia triacanthos) tree growing next to a home in Michigan, USA, shown by zooming in on a focal point above the tree's base (successive photographs from left to right, with full tree grayed out in background). Photo credit: Janet MacFarlane. These photographs illustrate the article “Fractal dimension of tree crowns explains species functional-trait responses to urban environments at different scales” by Georgios Arseniou and David W. MacFarlane published in Ecological Applications. https://doi.org/10.1002/eap.2297.

Seemingly Unrelated Mixed-Effects Biomass Models for Black Locust in West Poland

Information about tree biomass is important not only in the assessment of wood resources but also in the process of preparing forest management plans, as well as for estimating carbon stocks and their flow in forest ecosystems. The study aimed to develop empirical models for determining the dry mass of the aboveground parts of black locust trees and their components (stem, branches, and leaves). The research was carried out based on data collected in 13 stands (a total of 38 sample trees) of black locust located in western Poland. The model system was developed based on multivariate mixed-effect models using two approaches. In the first approach, biomass components and tree height were defined as dependent variables, while diameter at breast height was used as an independent variable. In the second approach, biomass components and diameter at breast height were dependent variables and tree height was defined as the independent variable. Both approaches enable the fixed-effect and cross-model random-effect prediction of aboveground dry biomass components of black locust. Cross-model random-effect prediction was obtained using additional measurements of two extreme trees, defined as trees characterized by the smallest and largest diameter at breast height in sample plot. This type of prediction is more precise (root mean square error for stem dry biomass for both approaches equals 77.603 and 188.139, respectively) than that of fixed-effects prediction (root mean square error for stem dry biomass for both approaches equals 238.716 and 206.933, respectively). The use of height as an independent variable increases the possibility of the practical application of the proposed solutions using remote data sources.