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Recent outbreaks of engraver beetles, Ips spp. De Geer (Coleoptera: Curculionidae; Scolytinae), in ponderosa pine, Pinus ponderosa var. scopulorum Engelm. (Pinales: Pinaceae), forests of northern Arizona have resulted in widespread tree mortality. Current treatment options, such as spraying individual P. ponderosa with insecticides or deep watering of P. ponderosa in urban and periurban settings, are limited in applicability and scale. Thinning stands to increase tree vigor is also recommended, but appropriate timing is crucial. Antiaggregation pheromones, widely used to protect high-value trees or areas against attacks by several species of Dendroctonus Erichson (Coleoptera: Curculionidae; Scolytinae), would provide a feasible alternative with less environmental impacts than current treatments. We evaluated the efficacy of the antiaggregation pheromone verbenone (4,6,6-trimethylbicyclo[3.1.1]hept-3-en-2-one) in reducing attraction of pine engraver, I. pini (Say), to funnel traps baited with their aggregation pheromone in two trapping assays. Treatments included 1) unbaited control, 2) aggregation pheromone (bait), 3) bait with verbenone deployed from a pouch, and 4) bait with verbenone deployed from a flowable and biodegradable formulation (SPLAT Verb, ISCA Technologies Inc., Riverside, CA). Unbaited traps caught no beetles. In both assays, baited traps caught significantly more I. pini than traps with either formulation of verbenone, and no significant difference was observed between the verbenone pouch and SPLAT Verb. In the second assay, we also examined responses of Temnochila chlorodia (Mannerheim) (Coleoptera: Trogositidae), a common bark beetle predator. Traps containing verbenone pouches caught significantly fewer T. chlorodia than the baited control and SPLAT Verb treatments. We conclude that verbenone shows promise for reducing tree mortality from I. pini., (Published by Oxford University Press on behalf of Entomological Society of America 2020.)

• A root pruning (trenching) study was carried out on mature roadside Quercus virginiana. • Water stress symptoms were present for 440 days when trenches were made at 3 times DBH. • Root pruning reduced shoot elongation and leaf area one growing season after root severance. • The trunk diameters of trees closest to a road grew less than those further away. • Root pruning in trenches should not be undertaken closer than 6 times DBH. Conflicts between trees and infrastructure installation or repair occur frequently in the urban environment and may result in damage to or complete removal of tree roots. We monitored the responses of trees to linear root cutting and examined the effects of the presence of a road within tree root zones. Mature Quercus virginiana Mill trees (n = 31) were exposed to three root pruning treatments (plus a control) consisting of a trench on one side of the tree, offset by a distance as a multiple of trunk diameter (3x, 6x and 12x). Roots were severed manually, and their diameters were measured at the cut point to estimate a total cross-sectional area of severed roots. The total severed root cross-sectional area was subsequently expressed as a ratio of whole trunk cross-sectional areas (termed Ar (BH)), as well as trunk conductive sapwood areas (termed As (BH)) at breast height (1.4 m). The shortest horizontal distance between the tree bases and the edge of a nearby road was also recorded and included in statistical analyses as a continuous variable. Linear root cutting reduced shoot extension and leaf area by as much 146.13 mm (p < 0.01) and 2.92 cm2 (p < 0.001) respectively, one growing season after root severance. Trees nearer the road had significantly reduced trunk diameter growth (p < 0.05), independent of root severance effects, i.e. 12x, 6x and 3x treatments. Pre-dawn leaf water potential was negatively affected for all treatments (p < 0.05) and the symptoms of water stress persisted in the 3x treatment for 440 days. Ar (BH) and As (BH) ratios were regressed against physiological (predawn leaf water potential (Ψ), stomatal conductance (g s), leaf temperature (T) and two chlorophyll fluorescence variables (Fv/Fm and Fv/Fo)) and growth (trunk diameter, shoot extension and leaf area) responses. Ar (BH) was a significant predictor of Ψ, Fv/Fm, Fv/Fo, shoot extension and leaf area responses after one growing season, although model strength varied (R 2 = 0.75, 0.14, 0.16, 0.18, 0.24 respectively). To avoid sustained water stress symptoms, linear root cutting on Q. virginiana should not be undertaken closer to trees than six times DBH, equating to ≈ 25% root system loss. [ABSTRACT FROM AUTHOR]

A total of 128 Polish professionals (active and future designers, construction employees, and public officials) were questioned about their awareness and experience of tree protection practice in a survey conducted during tree diagnostic training sessions. According to the experienced professionals, trees were not protected at all in a significant proportion of projects. In the experience of nearly two thirds of professionals, trees on construction sites were protected in less than 60% of the projects in which they were involved. Half of respondents estimated that in over 60% of the projects where any protection was applied it was insufficient. Constraints related to the shape of the construction site, lack of funds, and insufficient knowledge were the main factors leading to the lack of tree protection. The main reason for any tree protection being in place was the legal regulations. Although respondents did not perceive the regulations as a source of knowledge, they believed that effective enforcement of penalties could be one crucial way to protect trees on construction sites, alongside specialist support. According to the results of the survey, awareness of the value of trees did not lead to tree protection. Respondents rated highly their knowledge about the influence of soil properties on tree survival and development, the growth and reaction of trees to damage, and tree protection in construction projects, but nevertheless admitted that they lacked knowledge of the technical issues of tree protection. [ABSTRACT FROM AUTHOR]

Trees help create sustainable urban systems by providing important functions aligned with the three dimensions of sustainability, i.e., environment, economy, and society. Yet urban forest loss remains a problem in expanding metropolitan regions. To accrue urban forest services, municipalities have enacted tree preservation ordinances (TPO) to regulate tree removal. These ordinances describe not only how cities manage their urban forests but also what urban forest services they value. The goals of this research are to locate cities with TPOs in Texas, compare the scope and intent of these ordinances, and assess the extent to which they reference the sustainability dimensions of urban forest services. We documented the parameters, extent, and conditions of tree protection found in TPOs via descriptive statistics and examined their statements of purpose for references to urban forest services through a quantitative content analysis (QCA). We found 60 municipalities possess TPOs, and most are in rapidly growing metropolitan areas. Our results indicate variations occur in their scope and intent. The majority of TPOs protect trees on private property but many also contain exemptions that potentially limit their effectiveness. Over half of TPOs contained a statement of purpose with references to one or more of the sustainability dimensions of urban forest services. Communities across metropolitan areas place more emphasis on the environment and society dimensions of sustainability. Overall, our results suggest that more communities should enact TPOs with less exemptions, and the sustainability dimensions of urban forests should be explored with equal vigor and stated more clearly so that all stakeholders are equipped with a better argument of not only why to write TPOs but why to enforce them. [ABSTRACT FROM AUTHOR]

• A study to monitor changes in tree value after root loss. • 149 trees exposed to root removal. • Four tree valuation methods used to appraise trees. • Root removal can reduce the value of urban trees. • Fine resolution methods best-suited for this purpose. Tree value is sometimes appraised to account for losses linked to insurance claims or legal disputes. In many of the appraisal methods used, tree value is influenced by vitality, size, and lifespan. These three factors can all be negatively impacted by nearby construction activities – ultimately impacting the monetary value of urban trees and the greater urban forest. The objectives of this study were to determine whether tree value was affected by root pruning, and to compare the effectiveness of four common, parametric tree appraisal methods for this purpose. Data from three individual root pruning studies (with varying levels of root pruning) were used. Four different tree valuation methods (CTLA Trunk Formula Method 9th Edition (CTLA), the Revised Burnley Method (Burnley), the Helliwell Method (Helliwell), and the Standard Tree Evaluation Method (STEM)) were used to assess the value of trees prior to and one growing season after root removal, as well as the average of all four methods. By examining the effects of root removal (reduced growth and vitality) over the course of a growing season, the results show that appraised tree value was negatively affected (Δ value (%)) by root pruning. A general trend towards greater loss in value with increasing root removal intensity was observed for all methods for one or more treatment type (p < 0.01) when compared to control (non-root pruned) trees. The values appraised using the CTLA and Burnley methods changed incrementally across treatments given the fine resolution of the scales in the awarding criteria. STEM and Helliwell were generally insensitive to root removal treatments. Linear mixed model analyses using four independent variables (maximum severed root diameter, % tree protection zone removed, total number of severed roots, and an allometric variable (Ar (GL)) defined as the total cross-sectional area of severed roots as a proportion of trunk cross-sectional area at ground level) revealed that % tree protection zone removal was the best performing tool for predicting percentage loss in value following root removal. Our results may be useful to those seeking compensation when tree damage has occurred due to construction-related activities. [ABSTRACT FROM AUTHOR]

The marula tree (Sclerocarya birrea subsp. caffra), a common species in sub-Saharan Africa, grows naturally in both protected and communal land. Although considerable research has been undertaken on these trees in southern Africa, to the authors' knowledge, the attitudes of local communities towards the protection of marula trees, particularly in communal land, has not been researched. This study intends to fill this gap in knowledge by examining the attitudes of local people towards conservation of marula trees. Studying the attitudes of people can provide insights on how they behave and how they are willing to coexist with S. birrea. The case study is set in Limpopo Province of South Africa in the villages of Ha-Mashau (Thondoni) and Ha-Mashamba where marula trees grow naturally. To fulfil the aim of this study, door-to-door surveys were carried out in 2018 and questionnaire interviews were used as the main data collection tool in 150 randomly selected households. The study revealed that local communities in the study area had positive attitudes towards conservation of marula trees. Strategies that are used by local communities to protect marula trees in communal land are discussed. [ABSTRACT FROM AUTHOR]