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The threats posed by the buprestid beetles emerald ash borer (Agrilus planipennis Fairmaire) and bronze birch borer (Agrilus anxius Gory) have been the subject of considerable research, primarily to develop methods for detection and management of the pests. PREPSYS, a Euphresco project, has worked with collaborators globally to assess the ‘state of the art’ for the two insect pests and to identify those measures that would best prepare Europe for potential invasion by the pests, especially emerald ash borer which is now in the western part of Russia and in eastern Ukraine. Building on an excellent exchange of knowledge and discussion at the OECD-sponsored international conference held in Vienna in October 2018, the concept of a European Toolbox to increase preparedness for dealing with the pests has been developed. This includes key components including surveillance, direct intervention, use of natural enemies and increased awareness of the problems associated with the pests. Collaboration is essential in delivering and refining the European Toolbox.

One of the main aims of EPPO is to help its member countries to prevent entry or spread of dangerous pests (plant quarantine). The Organization has therefore been given the task of identifying pests which may present a risk (early warning/horizon scanning), evaluating their risk for the region and making proposals on the phytosanitary measures which can be taken against them (Pest Risk Analysis). Standards are also developed, including standards on how to eradicate and control pests. In addition to the development of Standards, activities on communication and citizen science (development of guidelines on raising public awareness and the production of toolkits to use in raising awareness campaigns) have also recently been started. The EPPO Secretariat was alerted by the National Plant Protection Organization (NPPO) of Sweden in 2003, and Norway in 2010, to two potential new pests, Emerald ash borer (EAB), Agrilus planipennis (Fairmaire) and Bronze birch borer, Agrilus anxius (Gory) respectively. Because of the importance of these two pests for forest species in the EPPO region, member countries agreed that EPPO recommendations should be prepared. The different EPPO activities relevant to A. planipennis and A. anxius are presented, highlighting the challenges they currently pose to the region.

We studied the mating behavior and reproductive biology of three members of the genus Agrilus: the bronze birch borer, Agrilus anxius Gory; the twolined chestnut borer, Agrilus bilineatus (Weber); and the emerald ash borer, Agrilus planipennis Fairmaire. All three species share a highly stereotyped mating behavior. However, the copulation duration of A. planipennis was 90% longer than that of its two congeners. Female reproductive tracts of the three species were anatomically similar, as were the spermatophores. Within the spermatophores, sperm were single in A. anxius and A. bilineatus, while in A. planipennis, sperm were bundled in groups of approximately 20 in a hyaline sheath. We found that field-caught A. anxius and A. bilineatus had higher rates of female insemination than A. planipennis. In additional studies with A. planipennis and A. anxius, we found that mating duration was related to mating success, and fecundity for A. planipennis, but not for A. anxius. For both A. planipennis and A. anxius, the spermatophore was passed to the female toward the end of the copulatory period. Sperm were found in the spermatheca immediately after copulation ended in A. planipennis and 30 min after copulation ended in A. anxius. We present possible explanations for these differences.

The bronze birch borer can emerge and establish itself in the PRA area. The most likely route of its infestation is intercontinental transport of birch wood from regions of natural occurrence of the agrophage. Suitable climatic conditions and the presence of host trees possible for colonization allow us to assume that Agrilus anxius can do damage to communities with birch trees in Poland. Its possible impact on such stands PRA area may be greater than in North America. Although trees attractive to the agrophage are common throughout the country they do not usually form monocultures, and their share in communities is usually small in species composition. For this reason, there is no risk of decay of entire stands, even in the case of complete elimination of birch from the ecosystems. If the species is detected in batches of transported wood raw material, the raw material should be disposed of, preferably by burning. This must be done as soon as possible, except during winter - when insect activity is limited and this procedure can be delayed in time. Once the presence of the bronze birch borer is established in the wild, in the PRA area, any methods of its eradication are unlikely to yield satisfactory results. Rapid detection of the species, which could increase the probability of success in controlling the agrophage is severely hampered for the following reasons: - it has a secretive lifestyle, and the observable adult forms are short-lived, - there are other similar species of the genus under the bark of birch trees in the PRA area, which can lead to misleading identification, especially in the preimaginal stages, - once the adults emerge, the insects quickly proceed to reproduce and colonize new trees, often located at a considerable distance from the plant in which they developed., PL; pl; PDF; kwarantanna@iorpib.poznan.pl

Plants respond to feeding injury by chewing insects by inducing both a general response to mechanical wounding and a specific response to herbivore-associated elicitors. In both cases, plant response involves complex biochemical and physiological changes. We compared chemical and physical responses of paper birch (B. papyrifera) and European white birch (B. pendula) stems to mechanical injury to determine if aspects of their wound response correspond with the much higher resistance of paper birch to bronze birch borer (Agrilus anxius). We also characterized stem responses to mechanical wounding plus bronze birch borer larval homogenate to determine if larval cues elicited a more specific response than mechanical wounding alone. In both species, wounding decreased concentrations of individual phenolics, total phenolics, and condensed tannins, perhaps because they were diverted to lignin biosynthesis, the concentration of which increased. Nitrogen concentration increased in both species while free amino acid concentrations declined, perhaps because they were utilized to synthesize proteins. Application of larval homogenate did not elicit a response different from that induced by mechanical injury. When comparing wound responses of the two birch species, phenolic profiles differed most conspicuously. However, multivariate analyses revealed no differences between constitutive and wound-induced phenolic profiles within each species, and the rate of wound periderm growth was equivalent between species. These results suggest that components of the wound response we measured may not contribute to interspecific variation in bronze birch borer resistance of paper birch and European white birch.

Bronze birch borer (Agrilus anxius Gory) (Coleoptera: Buprestidae), a specialist wood-borer endemic to North America, is prone to periodic outbreaks that have caused widespread mortality of birch (Betula spp.) in boreal and north temperate forests. It is also the key pest of birch in ornamental landscapes. Amenity plantings have extended the distribution of birch in North America, for which we report an updated map. Life history and phenology also are summarized. Larvae feed primarily on phloem tissue of stems and branches, which can girdle and kill trees. Stressors such as drought, elevated temperature, and defoliation predispose trees to bronze birch borer colonization and trigger outbreaks, which implicates the availability of suitable host material in the bottom-up regulation of populations. Stress imposed by climate change may increase the frequency of outbreaks and alter the distribution of birch. Bronze birch borer has a diverse array of natural enemies, but their role in top-down population regulation has not been studied. There is substantial interspecific variation in resistance to this insect. North American species share a coevolutionary history with bronze birch borer and are much more resistant than Eurasian species, which are evolutionarily naïve. Potential resistance mechanisms are reviewed. The high susceptibility of Eurasian birch species and climatic similarities of North America and Eurasia create high risk of widespread birch mortality in Eurasia if the borer was inadvertently introduced. Bronze birch borer can be managed in amenity plantings through selection of resistant birch species, plant health care practices, and insecticides.

Increasing inter-continental trade of wood chips for biofuel represents a significant risk of introducing invasive pest species that can cause biome-scale impacts on forest ecosystems. Some potentially invasive species have the capacity to cause high tree mortality on the Eurasian continent and could cause significant impacts on biodiversity and ecosystem functions. Because eradication of established species is difficult, there is a need for scientific studies that can evaluate the reliability of current import control practices to ensure lowest possible risk of establishment of potentially harmful species. We used a stochastic simulation model and sensitivity analyses to evaluate the chance of detecting harmful pests in imported wood chips by sampling according to the current use of internationally accepted standards. As an example, we focused on the North American beetle Agrilus anxius (bronze birch borer) that can cause 100% mortality of European and Asian birch species in North America. We si...

Bronze birch borer (Agrilus anxius Gory) is the key pest of birches (Betula spp.) in North America, several of which have been recommended for ornamental landscapes based on anecdotal reports of borer resistance that had not been confirmed experimentally. In a 20-yr common garden experiment initiated in 1979 in Ohio, North American birch species, including paper birch (Betula papyrifera Marshall), 'Whitespire' gray birch (Betula populifolia Marshall), and river birch (Betula nigra L.), were much more resistant to bronze birch borer than species indigenous to Europe and Asia, including European white birch (Betula pendula Roth), downy birch (Betula pubescens Ehrh.), monarch birch (Betula maximowicziana Regel), and Szechuan white birch (Betula szechuanica Jansson). Within 8 yr of planting, every European white, downy, and Szechuan birch had been colonized and killed, although 100% of monarch birch had been colonized and 88% of these plants were killed after nine years. Conversely, 97% of river birch, 76% of paper birch, and 73% Whitespire gray birch were alive 20 yr after planting, and river birch showed no evidence of colonization. This pattern is consistent with biogeographic theory of plant defense: North American birch species that share a coevolutionary history with bronze birch borer were much more resistant than naïve hosts endemic to Europe and Asia, possibly by virtue of evolution of targeted defenses. This information suggests that if bronze birch borer were introduced to Europe or Asia, it could threaten its hosts there on a continental scale. This study also exposed limitations of anecdotal observation as evidence of host plant resistance.

Ten cultivars of dogwoods (Cornus spp.) were evaluated in multi-year trials for relative reisistance to the dogwood borer, Synanthedon scitula (Harris); cold injury; canker disease, Botryosphaeria dothidea; spot anthracnose, Elsinoe corni; and powdery mildew, Oidium sp., Microsphaera sp., and Phyllactinia sp. Similarly, eight cultivars of birch (Betula spp.) were evaluated for resistance to the birch leafminer, Fenusa pusilla (Lepeletier); Japanese beetle, Popillia japonica Newman; aphids, Hamamelistes spinosus Shimer; the bronze birch borer, Agrilus anxius Gory; and leaf-spot, Cryptocline betularum. All cultivars of C. florida, C. kousa and C. kousa x florida were susceptible to dogwood borer, although the C. florida cultivars were surviving better than the others. Cornus mas and C. kousa cultivars were relatively resistant to powdery mildew while C. florida x kousa hybrids and C. florida ‘Cherokee Brave’ were intermediately resistant. Betula platyphylla szechuanica ‘Purpurea’ was highly susceptible to the bronze birch borer, whereas B. nigra and B. n. ‘Heritage’ were the most susceptible birches to aphid damage. Betula jacquemontii was highly susceptible to Japanese beetle defoliation. Betula pendula, B. nigra, and B. n. ‘Heritage’ were most susceptible to defoliation by birch leaf spot. This study suggests that dogwood and birch cultivars vary in susceptibility to key insect pests and diseases. Planting relatively resistant cultivars may be useful in managing perennial pests in urban landscapes.

On its own initiative the Norwegian Scientific Committee for Food Safety has conduct a risk characterization of ten insect pests and four fungal pests that may follow the import of deciduous wood chips from eastern North America, and that are potentially harmful to Norwegian forests and environment. The VKM Panel on Plant Health finds it important to get a better overview of plant pests, both listed and potential quarantine pests, which might follow the import of wood chips to Norway. As a first step toward a pest risk assessment of the commodity of wood chips, the panel decided to conduct a risk characterization. The ten insect species selected for risk characterization were: Agrilus anxius Agrilus planipennis Agrilus bilineatus Chrysobothris femorata Agrilus horni Agrilus granulatus liragus Agrilus granulatus granulatus Hylurgopinus rufipes Agrilus politus Scolytus schevyrewi Four fungal pest species The four selected fungal pest species were: Ceratocystis fagacearum Davidiella populorum Phellinus spiculosus Phellinus everhartii The ranking of the species given here is according to the likelihood of arriving with relevant pathways of wood chips, the presence of susceptible hosts in Norway, the similarity of climate between Norway and the areas of origin, and the severity of damages they may cause in Norwegian forests. The ranking order indicates which species could undergo full pest risk assessment first. However, the order is uncertain since the behaviour of the species under new conditions is unknown. Also, Agrilus anxius has already been risk assessed for Norway., NO; en; vkm@vkm.no

Outbreaks of bronze birch borer (BBB) (Agrilus anxius), a wood-boring beetle endemic to North America, have been associated with widespread mortality of birch (Betula spp.). There is substantial inter- and intra-specific variation in birch resistance to BBB. Species endemic to North America, such as paper birch (B. papyrifera), have coevolved with BBB and are more resistant than European and Asian birch species, such as European white birch (B. pendula), which lack an evolutionary history with BBB. Borer larvae feed on stem phloem tissue. Therefore, in search of potential resistance mechanisms against BBB, we compared the constitutive phenolic profile of stem phloem tissue of paper birch with that of European white birch. We also analyzed intraspecific variation in phenolic composition among clones and/or half-siblings of both species. Three phenolics (coumaroylquinic acid, betuloside pentoside A, and a diarylheptanoid hexoside) were detected only in paper birch, and concentrations of six other phenolics were significantly higher in paper birch. These differences may contribute to the high resistance of paper birch to BBB relative to European white birch. There was significant intraspecific variation in four of 17 phenolics found in paper birch and in five of 14 found in European white birch, but clones and half-siblings within each species could not be distinguished by phenolic composition using multivariate analysis.

Widespread paper birch (Betulapapyrifera Marsh.) mortality associated with the activity of the bronze birch borer (Agrilusanxius Gory) was observed across northern Michigan in 1991. This mortality occurred at two study sites on which paper birch growth has been intensively monitored since 1985. Recent warmer than normal growing seasons and lower than normal moisture availability are statistically associated with a reduction in annual diameter growth. On one study site 62% of the paper birch study trees were dead and 13% were visibly declining; on the other study site, although no trees were dead, 25% of the paper birch study trees were visibly declining. Growth reductions since 1985 suggest that the species was under climatic stress, making it more vulnerable to pest–pathogen activity. The evidence of the role of climatic conditions acting as a precursor to decline and mortality on these sites is of serious concern given recent projections of warmer temperatures and lower precipitation for this region by several global-climate models.

Mating behavior of the bronze birch borer, Agrilus anxius, was investigated under laboratory and outdoor conditions. Propensity to mate was greater for beetles more than 1-d-old. Duration of copulation tended to increase with increasing beetle age; 87% of mated females were inseminated and subsequently avoided sexual contact. Males mated more than once; previously mated males copulated sooner and for longer periods of time than naive males. Mating frequency did not influence female reproductive success.

A microsporidium was isolated from the bronze birch borer, Agrilus anxius Gory (Coleoptera: Buprestidae), collected near Sudbury and Sault Ste Marie, Canada. Light and electron microscopic investigations showed that gross pathology and ultrastructure of the investigated Cystosporogenes species was similar to those characterized and described for other Cystosporogenes species. Small subunit rRNA gene sequence data and comparative phylogenetic analysis confirmed that the microsporidian species from A. anxius is most closely related to the genus Cystosporogenes clade of microsporidia. Infection average in the Sudbury and Sault Ste Marie beetle populations was >80% and relatively stable in 2006-2007 but declined in 2008. Field prevalence of the A. anxius isolate, mechanisms that may potentially be involved in its horizontal (autoinfection) and vertical (transovarial) transmission, and disease dynamics are discussed. The congeneric relationship between Agrilus planipennis and A. anxius makes it imperative to study the virulence of this Cystosporogenes species in A. planipennis.

A test of Michigan half-sib progeny of paper birch (Betula papyrifera Marsh.) and European white birch (B. pendula Roth.) was conducted in Michigan to examine species variation in growth, bark color, and resistance to bronze birch borer (Agrilus anxius Gory). Paper birch was superior to European white birch in height and borer resistance at age 12 years from seed. Families of paper birch were identified that grew exceptionally well, had developed white bark within 6 years, and exhibited borer resistance. The magnitude of additive genetic variance and narrow-sense family heritability estimates for paper birch indicated that sufficient genetic variation and inheritance exist to support selection and breeding for height. Paper birch may be an acceptable substitute for European white birch as a landscape species in northeastern North America.

Spatial emergence patterns of the bronze birch borer, Agrilus anxius Gory, and associated parasite and woodpecker predation in European white birch, Betula pendula Roth, were examined. Beetle and total hole density (beetle + parasite + woodpecker) were significantly lower from stem bolts 6 m above ground, 0.1 to 5.0 cm in circumference, and with 0.1 to 1.5 mm bark thickness than bolts 1 to 3 m above ground, 5.1 to 60.0 cm circumference, and with 1.51 to 3.0 mm bark thickness. Significantly more emergence occurred from the southwestern quadrant of trees than from other quadrants. Beetle emergence and total hole densities were also significantly less from branches than from tree trunks.

Reproductive biology of the bronze birch borer, Agrilus anxius Gory, was examined by measuring the influence of host on maturation feeding period, fecundity, incubation period, egg viability, and longevity. Initially, females fed Betula pendula Roth leaves had the highest fecundity and egg hatchability. However, when large numbers of beetles were caged on an individual B. pendula in 1982, females did not oviposit. Fecundity and egg hatch varied on Populus deltoides Bartr. ex March between years but was consistently high, and the percentage of females ovipositing when fed this host was usually highest. Some beetles fed Quercus palustris Muenchh. or Salix elaeagnos Scop, produced eggs; no reproduction occurred on Acer saccharinum L. Host species and environmental variables influenced the beetle's reproductive biology, but some of the observed differences may be explained by reduced foliage quality resulting from inducible plant defense or spacing pheromones produced by beetles at high densities.

Results of the 2003 annual inventory of Wisconsin show about 15.9 million acres of forest land, over 21.9 billion cubic feet of live volume on forest land, and nearly 591 million dry tons of all live aboveground tree biomass on timberland. Gypsy moth, forest tent caterpillar, twolined chestnut borer, bronze birch borer, ash yellows, and oak wilt were among the pests of Wisconsin forests.

Results of the 2002 annual inventory of Wisconsin show about 16.0 million acres of forest land, over 22.2 billion cubic feet of live volume on forest land, and nearly 598 million dry tons of all live aboveground tree biomass on timberland. Gypsy moth, forest tent caterpillar, twolined chestnut borer, bronze birch borer, ash yellows, and white pine blister rust were among the pests of Wisconsin forests.

A mixed stand of 3.5-5.0 m tall birches planted in 1983 were evaluated in Aug 88 for BBB. Nine paper birches with old BBB exit holes, nine paper birches with gouting but no exit holes, 18 European birches with exit holes and 12 European birches with gouting only were selected for treatments. Each tree category was divided into blocks of 3 trees (=16 total replicates). On the date of application, 26 Aug 88, the soil moisture was low due to a drought. Normal rainfall returned for Sep and Oct. Mauget Inject-A-Cide B 1.0 ml injector units with inch mini-microfeeder tubes (normal feeder tubes are inch) were used at rates of one tube/tree with breast diameter height (BDH) less than 8.0 cm and 2 tubes/tree with BDH ≥ 8.0 cm. The feeder tubes were attached at the root flare zone and the units remained on the trees until empty. Cygon 4 E was applied by mixing 150 ml in 1.0 gal of water and pouring around the tree base within a 0.3 m radius. Untreated checks received 1.0 gal of water. During the wk of 29 May 89 a 1.0 m long section of each tree was marked with a waterproof pen about 1.5 to 2.0 m above ground level. All existing BBB exit holes were marked. All trees were examined on 9 Aug 89 and the number of new exit holes/1.0 m segment were recorded.

Predation and parasitism of immatures of the bronze birch borer, Agrilus anxius Gory, in European white birch in Pennsylvania were studied. Egg parasitism was 7% , and was due primarily to two encyrtids, Ooencyrtus sp. and Avetianella sp. Five species of larval parasites were recovered. Tetrastichus sp. (Eulophidae), the most common parasite, and Eurytoma sp. (Eurytomidae) were new records from A. anxius. Phasgonophora sulcata Westwood (Chalcididae), Atanycolus charus (Riley) (Braconidae), and an undetermined ichneumonid were less common. Larval parasitism by all species amounted to 18%. Predation by woodpeckers reduced the overwintering larval population by 60%.

European white birch, Betula pendula Roth, bolts infested with bronze birch borer, Agrilus anxius Gory, were subjected to 4 post-felling treatments to delay or expedite adult emergence. Felling date and bolt end treatment significantly influenced beetle emergence density. Fall-felled, unsealed bolts with 1 end standing in water produced few beetles. Although rearing room temperature, relative humidity, and weeks of cold storage did not affect numbers of beetles produced, these factors could be used to expedite or delay beetle emergence. This study demonstrates that infested birch wood can be manipulated to produce bronze birch borer adults for laboratory studies when beetles are not available otherwise.

The bronze birch borer, Agrilus anxius Gory (Coleoptera: Buprestidae), has four larval instars in young European white birch, Betula pendula Roth, planted in Pennsylvania for surface mine reforestation. Of seven morphological variables measured, the width of the peristoma, an exposed sclerotized portion of the head capsule, provides the clearest separation of instars. Although any of three variables measured in the caudal region of the larva is satisfactory, the anteriormost width of the urogomphi is the most reliable caudal variable.

Distributions of immature stages of the bronze birch borer, Agrilus anxius Gory (Coleoptera: Buprestidae), infesting young European white birch, Betula pendula Roth, were studied on a surface mine reforestation site in Pennsylvania. Eggs of A. anxius were common on boles of trees from mid-June through mid-August, in clusters of up to 14 eggs. Almost 70% of the eggs were in crevices in the dark triangular patch at branch origins. Larvae were present throughout the year. Fourth instars comprised 93.1% of the overwintering population.Vertical distributions of eggs, larvae, and pupae along the bole were random relative to available surface area. Consequently, each stage was more abundant on the lower half than on the upper half of trees. Eggs and first instars were concentrated on the northeast, or shaded, side of trees. Second and third instars were distributed randomly around the bole. Fourth instars overwintered and pupated primarily on the southwest aspect.

It is not so easy, in the case of shade trees, to establish the relation between a generally unsatisfactory condition and insect infestation as in the case of fruit trees. There is no difficulty in seeing the connection between a dying tree and the work of cambium borers, such as the two-lined chestnut borer, the bronze birch borer, the spotted hemlock borer and the sugar maple borer. The scale insects constitute a relatively inconspicuous group capable of causing serious injury. The oyster shell scale and the elm bark louse, in particular, are occasionally very abundant and injurious, the former frequently killing good sized ash and poplar trees. The tulip tree scale is another pernicious insect. The aphids or plant lice are occasionally extremely abundant and while the immediate results may not be as striking as in the case of severe infestations by scale insects, there is undoubtedly a lowering of vitality, through interference with the functioning of the leaf. A small series of gall insects produce appreciable injury. This is especially true of a number of the knotty oak galls. In the case of shade trees, symmetry and sightliness are important factors, consequently insects which affect the normal development of the tree by preventing growth or killing branches are undesirable. The leaf eating insects, such as canker worms and the elm leaf beetle frequently devour a considerable proportion of the foliage, and this can but have a material effect upon the vigor and the growth of the tree. The periodical outbreaks of the Pandora moth in western pine forests have resulted in the reduction in the width of the annual rings by 80%. It is more than probable that severe infestations by scale insects and plant lice materially affect the thickness of the annual rings. There are other causes which may produce this, namely deficient rainfall and thin soil or a gradual depletion in soil fertility. It is not easy to differentiate between the various causes. The mere reduction in the amount of wood produced in anyone season is not the most serious phase of the problem. Weakening of branches or leaves is usually evident first in the upper limbs and is followed by greater susceptibility to both insect attack and fungous infection. It is believed that a combination of these agencies, each of variable importance under different conditions, explains in considerable measure the many dying tips generally assoicated with what we consider a “stagheaded” condition. We need more data as to the part insects play in producing such conditions. How much of this can be traced back to earlier attacks by insects? Shade trees have a material value and it is our contention that this should be taken into account in estimating the economic importance of shade tree insects. We believe it much more economical to protect a tree from insect depredations than it is to replace such a tree with one of equal size.

Agrilus anxius was described by Gory (1841), and later given the name “bronze birch borer” by Chittenden (1898). It was recently separated from a closely allied species attacking poplar, A. liragus (Barter and Brown, 1949; Smith, 1949). The borer is native to North America and occurs apparently throughout most of the range olf birch from Newfoundland to British Columbia, and south to New Jersey, Ohio, and Colorado (Barter and Brown, 1949; Fisher, 1928).

There are many peculiarities in relation to insect attacks which have not been explained. Some are undoubtedly physiological, others may have a distinct relation to the vigor or condition of the plant, as in the case of the Hessian fly, Phytophaga destructor Say, the lace bugs of rhododendrons and azaleas, Stephanitis rhododendri Horv. and Stephanitis pyrioides Scott, respectively. Injury is also somewhat proportionate to the size and vigor of the host, as evidenced by European corn borer, Pyrausta nubilalis Hubn., infestations. Extended injuries by the elm leaf beetle, Galerucella xanthomelaena Schrank, are dependent in considerable measure upon favorable climatic conditions, these latter undoubtedly resulting in a less vigorous growth. A peculiar and unexplained physiologic-al reaction by gipsy moth larvae, Porthetria dispar Linn., is also mentioned. Evidence available indicates that a number of the cambium borers, namely the bronze birch borer, Agrilus anxius Gory, the two-lined chestnut borer, Agrilus bilineatus Web., the hickory bark beetle, Scolytus quadrispinosus Say, and the cedar bark beetle, Phloeosinus dentatus Say. successfully invade trees with a lowered vitality and that in the case of the first named, it is possible to stimulate growth by feeding and aid trees to actually destroy the borers. It is suggested that a uniform and satisfactory supply of moisture throughout the season and feeding to promote a vigorous growth may be valuable preventive measures in the case of certain insects at least.

Yellow birch was once the most important species of hardwood in Eastern Canada. During the last 20 to 25 years, "birch dieback" has caused losses in the three Maritime Provinces estimated at 2,400 million cu. ft. A considerable number of species of insects feed normally on birch foliage, but none was found responsible for the disease. The bronze birch borer played a very important role in that its presence may have determined whether a tree succumbed to or recovered from decline. No fungi or bacteria found on twigs, leaves or roots were virulent enough to be considered the cause. No permanent or temporary stoppages were found in water-conducting tissues and occurrence of dieback has not been related to drought. Slight increases in soil temperature caused mortality of rootlets, which resulted in bare twigs, and small, slightly curled and chlorotic foliage. Several symptoms characteristic of virus diseases are being investigated. It is predicted that birch will form a substantial component of future forest stands, but high-grade products will be obtained only through application of intensive silviculture. Some recommended treatments are given.

The Norway maple leaf stem miner, Nepticula sericopeza Zell., is somewhat generally distributed in southeastern New York and southwestern New England. Spraying with a nicotine molasses soap combination in May apparently gives excellent control. The red cedar aphis, Lachnus sabinae Gill., provided an excellent outdoor demonstration of injuries earlier associated provisionally with this species. The hackberry nipple gall, Pachypsylla mamma Riley, and the hackberry bud gall, Pachypsylla gemma Riley, are both common on hackberry. The former is readily controlled with a nicotine molasses spray applied about the middle of May and the latter with the same materials applied about June 10th. The insecticide kills many adults and apparently destroys the eggs. The knotty oak galls, Andricus punctatus Bass, A. cornigerus O. S., and A. clavigerus Ashm. are common on the red oak, pin oak and willow oak respectively, in some instances causing serious injury. The alternate generation of the former two develops in a small blister leaf gall. The hackberry leaf aphid, Myzocallis fumipennellus Fitch, is responsible for a very general yellowish spotting and browning of hickory leaves in early fall, in some cases, most of the leaves being killed. The bronze birch borer, Agrilus anxius Gory, and the two-lined chestnut borer, Agrilus bilineatus Weber, are generally distributed pests. Available data show that feeding of birches frequently enables the trees to outgrow somewhat serious infestations. Work by the two-lined chestnut borer is very frequent on trees indirectly injured by grading or building operations. The filbert bud mite, Eriophyes avell.anae Nal., produces greatly enlarged buds on European filberts and has been associated with some severe injury. A paste of calcium cyanide and castor oil applied to areas infested by the linden borer, Saperda vestita Say, have given very encouraging results.

The elm leaf beetle, Galerucella xanthomelaena, the Japanese beetle, Popillia japonica, the willow leaf beetle, Plagiodera versicolora, and the larch case bearer, ColeoPhoralaricella, were all abundant and possibly as destructive as in 1931. The occurrence of many parasites, Scolia dubia, on a lawn badly injured by the Japanese beetle and the green June beetle, Allorhina nitida, is recorded. Notes are given on the cypress leaf miner, Recurvaria apicitripunctella, a leaf beetle, Calligrapha philadelPhica, a privet thrips, Dendrothrips ornatus, and the black vine weevil, Brachyrhinus sulcatus. The two-lined chestnut borer, Agrilus bilineatus, and the bronze birch borer, Agrilus anxius, were killing trees locally. They were probably favored by the series of droughts in recent years. A bad infestation of rhododendron stems by the pitted ambrosia beetle, Corthylus punctatissimus, is recorded from Long Island, and the local prevalence of the leopard moth, Zeuzera pyrina, on Nantucket Island is reported. The oak pruner, Hypermallus villosus, has been extraordinarily abundant in. the northeastern United States. The fruit tree bark beetle, Scolytus rugulosus, and the European elm bark beetle, Scolytus multistriatus, have developed in great numbers on weak trees. The European pine shoot moth, Rhyacionia buoliana, continues as a destructive pest, and the Nantucket pine moth, Rhyacionia frustrana, has been extremely abundant on Nantucket Island. The recently discovered white pine tip moth, Eucosma gloriola, is becoming somewhat widely distributed, though not seriously injurious. The unusual local abundance of the pitch mass borer, Parharmonia pini, was observed at Bedford Hills, N. Y. The elm lace bug, Corythucha ulmi, and the sycamore lace bug, Corythucha ciliata, have been unusually prevalent, and the work of the linden lace bug, GargaPhia tiliae, came to notice on account of its abundance at Stockbridge, Mass. An elm pouch gall, ErioPhyes sp., was very numerous on elms at Wakefield and Lynnfield, Mass., and the maple bladder gall, Phyllocoptes lJ.uadripes, was extremely abundant on a soft maple at Newburgh, N. Y. The tulip tree scale, Toumeyella liriodendri, was quite prevalent, though it was preyed upon locally by the caterpillars of Laetillia coccidivora. The Euonymus scale, ChionasPis euonymi, has been extremely numerous in various plantings. A new hemlock leaf scale, Fiorinia, near F. fioriniae Kuwana, is becoming established and injurious at several Long Island and southwestern New England localities. The Chinese mantid, Paratenodera sinensis, has been unusually abundant in southwestern New England and southeastern New York.

Investigations in control of the bronze birch borer, Agrilus anxius Gory, and the flat headed apple tree borer, Chrysobothris femorata (Olivier), were conducted at the Ohio Agricultural Experiment Station during 1956 and 1957. Several of the oregano phosphates and various concentrations of DDT were applied to the respective host trees. Parathion was consistently effective in the three tests in which it was used. The results with DDT were erratic, but the data indicate that one application of a relatively strong concentration of DDT combined with a liquid latex or polyethylene on the trunks of newly transplanted shade trees may be adequate for the control of the flat headed apple tree borer.