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Heterobasidion spp. root rot causes severe damage to forests throughout the northern temperate zone. In order to prevent Heterobasidion infection in summertime cuttings, stumps can be treated with urea or Phlebiopsis gigantea. In this study, the consumption of stump treatment materials and the quality of stump treatment work were investigated. A total of 46 harvesters were examined in May-November 2016 in Finland. The average stem size of softwood removal and softwood removal per hectare explained the consumption of stump treatment material. The quality of stump treatment work was good in the study. The best coverage was achieved with the stumps of 20-39 cm diameter at stump height (d0). It can be recommended that the harvester operator self-monitors and actively controls his/her treatment result in cutting work and sets the stump treatment equipment in a harvester if needed. The results also suggested that when cutting mostly small- and medium-diameter (d0 ≤ 39 cm) conifers, the stump treatment guide bars with relatively few (<18) open holes are used, and at the harvesting sites of large-diameter trees, the guide bars with a relatively great (>27) number of open holes are applied. [ABSTRACT FROM AUTHOR]

We tested 3-methylcyclohex-2-en-1-one (MCH) and an Acer kairomone blend (AKB) as repellent semiochemicals for area and single tree protection to prevent spruce beetle (Dendroctonus rufipennis Kirby) attacks at locations in Utah and New Mexico. In the area protection study, we compared host infestation rates of MCH applications at three densities (20, 40, and 80 g MCH ha-1) against a control treatment over 0.64 ha plots centered within ~1.25 ha treatment blocks. All treatments included two baited funnel traps within the plot to assure spruce beetle pressure. Following beetle attack, plots were surveyed for new spruce beetle attacks and to quantify stand characteristics. The probability of more severe spruce beetle attacks was significantly reduced, by ~50%, in each of the MCH area treatments compared with the control treatment but there was no significant treatment difference among the MCH deployment densities. For the single tree protection study, we compared attack rates of MCH, Acer kairomone blend (AKB), and MCH plus AKB on spruce beetle-baited trees against bait-only trees. Each treatment was applied over a range of host diameters to test for host size effects. Seventy-five percent of control trees were mass-attacked, about one-third of MCH- and AKB-alone spruce was mass-attacked, and no MCH plus AKB spruce were mass-attacked. These results suggest that MCH alone is a marginal area and single tree protectant against spruce beetle but that deployment with other repellents can significantly increase treatment efficacy. [ABSTRACT FROM AUTHOR]

Forest Managers in the UK and elsewhere are facing new threats such as climate change and novel pests and diseases. Strategies seek to coordinate and steer appropriate responses through raising awareness and encouraging action but little is known about how individual managers respond to disease threats. We studied how managers have responded to the threat of Dothistroma Needle Blight (DNB), a disease which can affect growth and cause mortality of many pine species, and the key frames influencing their responses. Frames involve values and beliefs and allow people to make sense of, and interpret, events, experiences or issues. Interviews revealed broad awareness of the disease and threat it poses, but also high levels of inaction. Lack of action was associated with several framings grouped around causes and perceived severity of DNB, locating responsibility for prevention and management, mistrust/scepticism of advice and uncertainties over the future impact. These framings need to be considered as strategies are refined and new knowledge of disease behaviour is communicated to those from whom action is required. [ABSTRACT FROM AUTHOR]

BACKGROUND The invasive goldspotted oak borer, Agrilus auroguttatus, is threatening the health and survival of oak trees in San Diego County, California. From two sites in the core area of the infestation, we report a 2.5 year investigation of the impact of A. auroguttatus on coast live oak, Quercus agrifolia, before and after treatment with two systemic insecticides, emamectin benzoate ( EB) and imidacloprid ( IC). RESULTS None of the 446 survey trees died during the study. The crown dieback rating of most trees at both study sites remained unchanged, regardless of insecticide treatment. A higher cumulative increase in the number of A. auroguttatus emergence holes was observed on trees that were previously infested and on trees with larger diameters. Over the 2.5 year period, the new infestation rates of initially uninfested trees across the untreated and treated groups were 50% ( EB) and 32% ( IC), and neither EB nor IC treatment affected cumulative increases in the number of emergence holes. EB-injected trees did not have significant annual increases in the number of A. auroguttatus emergence holes at either 1.5 or 2.5 years compared with that at 0.5 years, whereas untreated trees had significant annual increases. Although IC-injected trees had a significantly greater annual increment in the number of emergence holes than untreated trees during the last year of the study, treated trees had significant reductions in annual increases in emergence holes at both 1.5 and 2.5 years compared with that at 0.5 years. Untreated trees had no significant reduction in the annual increase in emergence holes at 1.5 and 2.5 years. CONCLUSIONS A. auroguttatus preferentially attacked previously infested and larger (diameter at breast height > 15-30 cm) oak trees, but the attacks led to very gradual changes in the health of the trees. Both EB and IC provided minor suppressive effects on A. auroguttatus emergence. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

This paper summarizes the current knowledge of phytoplasma diseases of forest and landscape trees and shrubs, with special reference to molecular and taxonomic aspects of the associated phytoplasmas in the light of the plethora of data generated over the last years. Phytoplasma diseases of such kind of trees and shrubs are of considerable economic and ecological significance throughout the world, either because of the local impact or of their widespread distribution. However, information is still missing on many aspects of some of these diseases, including insect vectors, phytoplasma-vector relationships, phytoplasma-host plant interactions, strain virulence, strain interference, host tolerance, host range, and impact of the infections on the growth and yield of affected plants. In some instances, phytoplasma-infected forest and landscape trees and shrubs can serve as reservoirs of phytoplasmas affecting agricultural crops. Latent phytoplasma infections in some forest and landscape trees and shrubs are common. [ABSTRACT FROM AUTHOR]

Athel, saltcedar, siempreverde, rompeviento, or pinabete (Tamarix aphylla (L.) Karsten) is an exotic ornamental tree important for shade and wind protection in northern Mexico. There, the tree is defoliated by Diorhabda beetles, especially the subtropical tamarisk beetle, Diorhabda sublineata (Lucas), introduced for biological control of other invasive, shrubby Tamarix spp. The damage is conspicuous in Mexican communities in the Rio Grande and Conchos River basins, in Chihuahua State. To protect athel trees against damage by D. sublineata, we evaluated the effect of insecticide treatment on trees (one drench, 70 g active ingredient of imidacloprid per tree, for trees with approximately 1-m-diameter trunk bases) on foliage consumption by and insect knock-down of Diorhabda beetles at Ojinaga, Chihuahua, Mexico. One hundred sixteen days after treatment, fresh foliage was taken from treated and check trees to feed D. sublineata adults and larvae in a laboratory. The parameters of insecticide performance were: quantities of excrement (droppings) produced (as indicator of foliage consumption) and irreversible knockdown and convulsions of beetles; both were evaluated after insects were exposed to field-treated foliage for 14 hours in the laboratory. After this time, 100% of adult insects on non-treated foliage produced large amounts of droppings and showed no knockdown; on the other hand, when adult insects were fed foliage from the two treated sites, 100 and 86.6% produced few droppings and 33.3 and 42.2% showed knockdown, respectively. When fed foliage from the nontreated tree for 14 hours, 100% of larvae produced large amounts of droppings and showed no knockdown, while 87.5 and 50% of larvae produced few droppings and 47.5 and 28.7% showed knockdown when fed foliage from imidacloprid-treated sites. The amount of droppings and number of knocked-down insects and larvae were significantly different among treated and check trees. Drench application of imidacloprid can be a simple tool to prevent undesirable defoliation of athel trees at Chihuahua. [ABSTRACT FROM AUTHOR]

The Chinese white pine beetle (Dendroctonus armandi Tsai and Li) is the causal organism for the colossal death of the Chinese white pine (Pinus armandi Fr). We investigated the change of monoterpenes in the stem pholem and xylem in P. armandi saplings at 4 days, 8 days, and 30 days after treatment using treatment (MeJa + Tween-20 and Tween-20 as control) and untreated. GC-MS analysis found that the total monoterpene concentrations in the pholem and xylem in MeJa-treated saplings increased signifi cantly compared with control or untreated saplings. Additionally, the proportions of β-pinene in the stem pholem, β-myrcene in the stem xylem, and limonene + β-phellandrene in both pholem and xylem of MeJa-treated saplings were increased significantly compared with control or untreated saplings. Based on our results, we suggest that by increasing the total concentration of monoterpene and the concentrations of β-myrcene, β-pinene and limonene + β-phellandrene maybe play an important defensive role against insect pests in P. armandi defense. [ABSTRACT FROM AUTHOR]

Trees and forests provide a wide variety of ecosystem services in addition to timber, food, and other provisioning services. New approaches to pest and disease management are needed that take into account these multiple services and the different stakeholders they benefit, as well as the likelihood of greater threats in the future resulting from globalization and climate change. These considerations will affect priorities for both basic and applied research and how trade and phytosanitary regulations are formulated. [ABSTRACT FROM AUTHOR]

The article discusses a study on the influence of fungicides combined with water-retaining polymer on the root system of horsechestnut (Aesculus hippocastanum L.). For this study, increases in resistance against the foliar pathogen Guignardia leaf blotch (Guignardia aesculi) was monitored. The fungicides, combined with water-retaining polymer, was evaluated by spraying trees four times during the first growing season. It notes that none of the treated trees died due to Guignardia leaf blotch.

The article focuses on the recommendation to regulate the wood pest Agrilus anxius. It offers information related to concerns of the pest including its host, geographical distribution, and its life cycle. It offers guidelines on how to detect and identify the pest and examines the signifance of the pest to the economy.

Specific scope This standard describes the procedures for official control with the aim of containing and eradicating Bursaphelenchus xylophilus. Specific approval and amendment First approved in 2002-09. 1st revision approved in 2009-09. 2nd revision approved in 2010-09. 3rd revision approved in 2011-09. [ABSTRACT FROM AUTHOR]

Summary Lantana ( Lantana camara) has adverse effects on plant communities across Australia. Fire, sometimes recommended as a management strategy for Lantana, is likely to have both beneficial and detrimental effects on Lantana and native trees. It is therefore important to evaluate the regeneration of Lantana-invaded woody plant communities postfire. We examined the effect of Lantana removal by herbicide spray on both Lantana density and small tree (<5 cm diameter at breast height; DBH) attributes (abundance, height, DBH and diversity) in an area previously burnt. On a subset of the data, which was not sprayed, we also examined small tree attributes along a gradient of Lantana density. The herbicide treatment of postfire Lantana regrowth significantly reduced Lantana density compared to the areas left unmanaged by herbicide and increased the stem diameter of Celery Wood ( Polyscias elegans). We found that, as Lantana stem density increased in no-spray plots, the abundance of Poison Peach ( Trema tomentosa), Celery Wood, and Eucalyptus and allied genera ( Angophora and Corymbia) decreased. In addition, height of wattles ( Acacia irrorata and A. maidenii) increased with increasing Lantana density. As postfire regeneration of Lantana reduced abundance of some species, additional control of Lantana was required to assist community regeneration. [ABSTRACT FROM AUTHOR]

The temporal and small-scale spatial patterns of infestation by larval dogwood borer, Synanthedon scitula (Harris) were studied from 2002 to 2004 in two newly planted apple orchards in West Virginia and Virginia. Rootstock, tree variety, and cultural management practice were significantly associated with the presence and extent of dogwood borer infestation. In West Virginia, infestation was significantly greater on trees planted on M.26 rootstock compared with M.7 rootstock, and on trees fitted with tree guards compared with other trunk treatments. In Virginia, the proportion of infested trees was significantly greater for 'Idared' tree varieties compared with 'Buckeye Gala', and on trees fitted with tree guards compared with other trunk treatments. Median polishing technique was used to separate variability in the infestation data into large-scale variation (trend) induced mainly by treatments and small-scale variation. Variography was used to study the median-polished residuals of infestation that represent the small-scale variation. The results of variogram analysis of the median-polished residuals indicated that there were moderate to high degrees of aggregation in dogwood borer infestations on neighboring apple trees (Malus domestica Borkh.) with ranges of spatial autocorrelation from 2.8 to 17.0 m. The spatial patterns of the aggregation of infestation in the West Virginia and Virginia orchards were best described by the spherical and exponential semiovariogram models, respectively. Interpolated surface maps of the median-polished residuals revealed local hot spots, which were generally more prevalent within tree guard treatments, and were typically found where dogwood borer infestations originated. Results are discussed in relation to the sampling and management of dogwood borer larvae. [ABSTRACT FROM AUTHOR]

The article focuses on a study which evaluated the therapeutic disease management treatments for diseased pin oaks conducted from 2003 to 2007. The trees, which grew on golf course, street tree, and horse farm environments, were treated with root flare soil drenches of paclobutrazol, adjuvant-assisted basal trunk applications in anti-microbial compounds, and springtime root flare injections of oxytetracycline. It was found that tree life may be prolonged by therapeutic treatments that do not provide cure for trees infected with bacterial leaf scorch.

The article presents a study on the effectiveness of the insecticides imidacloprid and emanmectin benzoate in treating erythrina gall wasp (EGW) in coral trees. The study was administered by selecting 60 EGW infected trees treated with the two insecticides wherein its pre and post treatment injury as well as canopy foliage density was assessed using spherical densiometer. The study reveals that the insecticides affects canopy recovery and imidacloprid is the only effective treatment for EGW.

ABSTRACT Insects are commonly found by Hawaii's quarantine inspectors on Christmas trees imported from the Pacific Northwest. To reduce the risk of importing yellowjacket ( Vespula spp.) queens and other insects, an inspection and tree shaking certification program was begun in 1990. From 1993 to 2006, the annual percentage of shipped containers rated by Hawaii quarantine inspectors as moderately or highly infested with insects was significantly higher for manually shaken trees than for mechanically shaken trees. Between 1993 and 2001, 343 insect species in total were recovered from Christmas trees. Live western yellowjacket [Vespula pensylvanica (Saussure)] queens were intercepted both from containers certified as manually shaken and from containers certified as mechanically shaken. The standard manual shaking protocol removed about one-half of the queens from Douglas fir [Pseudotsuga menziesii (Mirb.) Franco] trees that were naturally infested with western yellowjacket queens. We investigated the use of preharvest sprays of permethrin as a complement to shaking procedures used to control yellowjackets and other insects. Western yellowjacket queens and honey bees (surrogates for wasp pests) were exposed to Noble fir foliage that had been sprayed in the field with permethrin >6 wk before harvest. Pesticide residues provided complete control (moribundity or mortality) in both species. The sprays did not affect needle retention or quality of Noble fir foliage. We conclude that preharvest sprays of pyrethroid insecticides could be used in combination with mechanical shaking to greatly reduce the quarantine risk of yellowjacket queens and other insects in exported Christmas trees. [ABSTRACT FROM AUTHOR]

The Douglas-fir beetle, Dendroctonus pseudot.sugae Hopkins (Coleoptera: Curculionidae), antiaggregation pheromone, 3-methylcyclohex-2-en-1-one (MCH), has been used by natural resource managers and landowners to protect high-value, high-risk trees from Douglas-fir beetle infestation throughout the western United States since 2000. Labor is a major portion of the cost of MCH treatments. MCH is applied by walking through treatment areas and stapling the formulated pheromone in bubble capsules to trees and other objects on a regular grid pattern. Reducing the number of MCH release points and increasing the distance between them could significantly reduce labor costs, particularly in areas with steep terrain or large volumes of woody debris that could impede the movement of applicators. This study compared the standard MCH application method with a method releasing MCH at a 3 times higher rate and placed at three times fewer release points per unit area. Treatments were applied to 2-ha plots simulating an operational application. Aggregation pheromone-baited traps were placed at plot centers to ensure that dispersing adult beetles would be present on all plots. Both MCH treatments were equally effective at preventing the infestation of live Douglas-fir, Pseudotsugae menziesii (Mirbel) Franco, trees (⩾30 cm diameter at breast height). These results confirm that MCH formulated to release at three times the current standard rate and placed at 3 times fewer points per unit area can effectively prevent the infestation of live Douglas-fir. The new treatment will significantly reduce the labor cost of MCH applications making them feasible for areas that may have previously been marginal economically. [ABSTRACT FROM AUTHOR]

The article focuses on the use of injected treatments for the management of Madrone Canker. An experiment testing injectable chemical fungicides and plant activators was performed on Pacific madrone trees inoculated with Fusicoccum arbuti. There was little correlation between fungicidal activity in culture and canker reduction in the field tests.

The article investigates the effect of Paclobutrazol (PBZ) on the growth of two Xylella fastidiosa isolates. X. fastidiosa is an insect-transmitted, bacterial plant pathogen that causes bacterial leaf scorch (BLS) in shade trees. PBZ, a diastereomeric triazole with both fungistatic and growth regulation properties, has been observed to alleviate symptoms of BLS if administered in high levels.

The mycoflora in living symptomless needles of Pinus sylvestris was investigated in three 5-8 year-old plantations in Southern Poland from 1987 to 1990. The needles from trees with symptoms of the autumn needle cast and from trees without such symptoms were treated separately. In total 960 of the current year and 720 of the previous year needles were collected. Fungi were isolated from 80.1 % of needles and 3671 cultures belonging to 86 fungal taxa were obtained. Seven species of fungi showed the rate of infection above 5 %: Anthostomella formosa, Lophodermium seditiosum, Cyclaneusma minus, Cenangium ferruginosum, Lophodermium pinastri, Sclerophoma pythiophila and Anthostomella pedemontana. The frequency of infection of needles by these species depended on needle age, season of the year, calendar year and site. The spread of fungi in needles was not too high. They were found in 35.8 % of needle sections (isolations were made from 10,080 sections). The needle base, middle and top were infected with more or less similar frequency, but the differences were considerable for the individual fungal species. Anthostomella formosa and A. pedemontana generally occurred slightly more frequently on needles of trees without symptoms of the autumn needle cast, while the other four common species (Cenangium ferruginosum, Cyclaneusma minus, Lophodermium pinastri, Lophodermium seditiosum) generally occurred more frequently on needles of trees showing such symptoms. There were considerable differences in this respect among plantations investigated. [ABSTRACT FROM AUTHOR]

Specific scope This standard describes the conduct of trials for the efficacy evaluation of plant growth regulators which have a dwarfing effect, either by limiting cell division and cell extension, or by stopping growth and destroying growing tips on ornamental trees and shrubs, used for hedging, ground cover or other amenity purposes. Specific approval and amendment First approved in 1993-09. Revision approved in 2011-09. [ABSTRACT FROM AUTHOR]

Discusses the current mission of the American Chestnut Foundation to find a cure for the fungal blight that has killed millions of chestnut trees in North America. How the American chestnut has greatly affected the lives of people and animals; The fungus that causes the blight; The organization's new approach to solving the problem; Foundation's research farm in southwestern Virginia; More.