Bjorkbom
White birch, Alaska birch, and grey birch are preferred native species. Still, some of the common stresses of urban landscape sites, such as soil compaction, de-icing salts, and lawn-care herbicides can also contribute to the sub-optional growth conditions that favor attack by the bronze birch borer. Poland
M. Liu
≈700 species are native to North America (Bright 1987). 2011) coupled with the climatic similarities of North America and Eurasia where Betula spp. R6-NR-FID-TP-05-04, Miscellaneous notes on Buprestidae and Schizopodidae occurring in the United States and Canada, including descriptions of previously known sexes of six, Notes on the distribution, synonymy, and biology of buprestidae (Coleoptera) of North America, Exploiting natural resistance as a management tactic for landscape plants, Comparative resistance of Asian, Eur., and North Am. Depending on the temperature, region, and host, the life cycle of A. anxius can be one or two years; colonies in warmer climates typically show a one-year life cycle while those in colder regions often have a two-year cycle (Katovich et al).Insect development is hastened with increased stress level of the host. Amenity plantings have extended the distribution of birch in North America, … However, the generalization that all white-barked species are highly susceptible to bronze birch borer is inaccurate (Miller et al.
Below, learn how to identify tree borers and get info on treatment. Feeding creates frass-filled galleries that disrupt transport of photosynthate and to some degree water (Anderson 1944, Barter 1957, Carlson and Knight 1969). However, interactions between birch species and bronze birch borer may be increasingly mediated by anthropogenic forces. However, when comparing paper birch and European white birch, the rate of wound periderm growth did not vary between species (Muilenburg 2010). U.S. Dep. Forest insect guilds: patterns of interactions with host trees, U.S. Dep. Its native range covers North America, where it survives in a wide range of ecological and climatic conditions. Males have a ventral groove on the first and second abdominal segments that are absent in females (Barter 1957). Known hosts: wide range of broadleaf tree species. Cattelino
However, in more resistant North American species (Nielsen et al. 2010); and age-related tree senescence (Balch and Prebble 1940, Auclair et al.
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.
1951, Barter 1957, Carlson and Knight 1969). Bloese
R.
1997), all of which were considered to have weakened host resistance and thus dramatically increased the availability of susceptible hosts. Buscarini
Spears
M.
Sikanen
The pattern of birch decline and bronze birch borer outbreak dynamics conform to the model of tree decline outlined by Sinclair (1964) and expanded by Manion (1981). 2011). Liechty
D.A. They live for 23 days as adults and are strong fliers, this means they can spread quickly. (Fisher 1929, Balch and Prebble 1940, Barter and Brown 1949, Carlson and Knight 1969). R.E. Birch is tolerant of high temperatures and resistant to bronze birch borer. R.M. No serious pests. J.T. L.S. S.H. The primary natural enemies of bronze birch borer include woodpeckers and diverse egg and larval parasitoid species (Nash et al. We forecast adult emergence based on the accumulation of growing degree days. Pruning should not be done from May 1 to July 1. B.J. Agric. Burnham
V.
Five and six instars also have been reported but without indication of how these numbers were determined (Hutchings 1923, Barter 1957). Mature trees then exhibit decreased energy as a result of intrinsic genetic factors, which when coupled with extrinsic environmental stressors, can lead to large-scale dieback and mortality (Mueller-Dombois 1986). J.W. P.D. wide host range of trees and shrubs, but prefers maple, apple, and poplar. Bronze birch borers are a type of grub that can kill roots, branches, and entire trees.
P.
These terminal structures traditionally have been termed urogomphi; however, Chamorro et al. Ornamental birch suchas European white birch and cutleaf weeping birch are also very susceptible.
290 Santamour: Stress and the Birch Borer adaptable to a wide range of soil types. D.F. It occurs throughout the range of birch in Canada and in all U.S. states between Maine and Idaho. Please report any sightings through TreeAlert. T.R. River birch, which is native to more southern reaches of North America, was not colonized, suggesting that it is immune to bronze birch borer (Nielsen et al. Herms
This large beetle lays its eggs underneath the bark of the tree, and the larvae burrow through the growing areas (cambium layer) and by preventing the movement and … S.J. Balch RE & Prebble JS (1940) The bronze birch borer and its relation to the dying of birch in New Brunswick forests. S.A.
L.
Natural enemies of immature stages of the bronze birch borer.
2012). C.P.-A. Adults must feed on foliage to achieve reproductive maturity (Barter 1957, Akers and Nielsen 1990), and in natural and laboratory conditions, have been observed to feed on several species including birch, willow (Salix), and poplar for 7–25 d, depending on species (Akers and Nielsen 1990). Emergence was quantified by weekly monitoring of appearance of new emergence holes on boles of colonized trees (source: D. A. Herms, The Dow Gardens, Midland, MI). Kondratieff
S.W.
The bronze birch borer (Agrilus anxius) is found throughout the birch range in the U.S. and Canada. H.P. Common tree borers. S.L. V.L. As with the Emerald Ash Borer, treatment should be done as a preventative or at the initial signs of canopy dieback. How to identify bronze birch borer and twolined chestnut borer Adults 1/4 to 1/2 inch long, slender, dark colored beetles. B.
The bronze birch borer, Agrilus anxius, is an increasingly common pest where it occurs in Oregon. This may be especially pronounced at the southern edge of the natural distribution of paper birch, potentially accelerating its northward migration (Haack 1996). W.A. Emerald Ash Borer). They deposit their eggs in bark crevices, preferring unshaded parts of the trees. P.
J.
J.
Between about 1930 and 1950, many gray birch trees, along with paper birch and yellow birch (Betula alleghaniensis), were affected and killed by birch dieback disease. Hoddle
Dissection of these galleries frequently reveals dead larvae encapsulated within wound periderm tissue (V.L.M. The adult is a copper/bronze colored slender beetle. Determination of larval instars of the bronze birch borer. Agric. Bronze birch borer attacks all native and introduced species of birch. Westcott
Bronze birch borers are iridescent and bronze colored. R.
(Anderson 1944) subsequently were shown to be of a separate species described as the bronze poplar borer (Barter and Brown 1949). Within-tree distributions and seasonality of immature stages of the bronze birch borer, Decline diseases of complex biotic and abiotic origin, Phytophagous insects as regulators of forest primary production, Azadirachtin: An effective systemic insecticide for control of, Paper birch and European white birch vary in growth and resistance to bronze birch borer, History of hardwood decline in the eastern United States, U.S. Dep. This native insect is a serious pest of any stressed birch tree (Betula species), but is most commonly found attacking the ornamental White Birch that are so common in our neighborhoods. Periodic outbreaks of this borer have led to widespread mortality of birch (Betula spp.)
This implies that birch resistance may result from the integration of physical and chemical defense mechanisms, which is consistent with the distinct chemical differences between paper birch and European white birch (Muilenburg et al. T.M. Julkunen-Tiitto
The four wood boring insects mentioned below attack a wide range of trees. In addition, trees in class 4 contained small areas of dead, darkened phloem tissue, and trees in class 5 contained large areas of dead phloem tissue (Ball and Simmons 1980). 1991, Nielsen et al.
D.
D.
R.W.
Evans
Reed
Appleby
2012). S.L. Auclair
Bronze birch borer larvae (size range 2–38 mm long) beneath the bark of silver birch. I concur and have seen impressive results after hiring a licensed commercial tree service. Boe
This tree has an attractive pendulous habit.
The bronze birch borer is a serious native insect pest.
Bronze Birch borer treatment. In some cases, natural enemies have caused substantial bronze birch borer mortality. Bronze Birch Borer is a more serious pest because it kills trunks, causing the death of most or all of the tree. Prasad
Birch is tolerant of high temperatures and resistant to bronze birch borer. Several insecticides, including systemic products (e.g., azadirachtin, dimethoate, emamectin benzoate, dicrotophos, dinotefuran, imidacloprid) and prophylactic bark sprays (e.g., bendiocarb, bifenthrin, carbaryl, chlorpyrifos, lindane, permethrin), have been shown to control Agrilus species to varying degrees (Appleby et al. Other authors have hypothesized that bronze birch borer can exist as both a secondary and primary colonizer, with its ecological role dependent on whether it exists at endemic or epidemic population densities, respectively (Balch and Prebble 1940, Nash et al.
Gen. Tech. I. Dreistadt
Why: The NPPO of Norway recently suggested that Agrilus anxius (Coleoptera: Buprestidae – bronze birch borer) could usefully be added to the EPPO Alert List.A.
white birch, Mating behavior of the bronze birch borer (Coleoptera: Buprestidae), The relation between host condition and attacks by the bronzed birch borer, Patterns and general characteristics of severe forest dieback from 1950 to 1995 in the northeastern United States, Principal forest dieback episodes in northern hardwoods: development of numeric indices of areal extent and severity, Predicting forest dieback in Maine, USA: a simple model based on soil frost and drought, The bronze birch borer and its relation to the dying of birch in New Brunswick forests, The relationship between bronze birch borer and birch dieback, Survival and development of the bronze poplar borer, Proceedings, 21st U.S. Department of Agriculture interagency research forum on invasive species 2010, Biosurveillance of Buprestidae in New York and New England, U.S. Dep. Bourque
Density-dependent responses of natural enemies to bronze birch borer populations have not been investigated. T.W. D.
Some birch decline events could also conform to the theory of cohort senescence (Mueller-Dombois 1986, Mueller-Dombois 1992, Auclair et al. S.
1973; Petrice and Haack 2006; Herms et al. From one year to the next, the damage progresses towards the trunk, resulting in tree mortality. Crawnshaw
Riggan
Morin
You still need to water it frequently when establishing it. McCullough
A parallel pattern has been documented for the congeneric emerald ash borer: Manchurian ash (F. mandshurica Rupr. Dedicated to Tree Preservation in the Urban Forest : or call (970) 484-3084: or call (970) 484-3084: This is during the borer flight period and it has been shown that female borers are attracted to fresh pruning wounds. Eggs hatch in 2 weeks or less, and the slender larvae tunnel immediately into the phloem tissue to construct their galle… 1993; MN DNR 1993, 1994), was consistent with the cohort senescence model. L. Cappaert
R.L. B. Katovich
LIFE CYCLE . Perhaps the most ecologically and economically important Agrilus species endemic to North America is bronze birch borer (A. anxius Gory), a specialist wood-borer of birch (Betula spp.) For example, in a 20-yr common garden study in Ohio, bronze birch borer colonization caused complete mortality of Eurasian species (European white birch, downy birch, monarch birch, and Szechuan white birch). (Santamour and McArdle 1989), a species indigenous to Japan, but later was identified as a cultivar of gray birch based on chemotaxonomic evidence (Santamour and Lundgren 1997). Forest Service, Pacific Northwest Region. Clark
The borers' tunneling weakens and kills trees by interrupting the flow of sap. The bronze birch borer occurs throughout the range of birches in Canada from Newfoundland to British Columbia but is most common in the southern portion of the provinces. Forestry Chronicle 16, 179–201.
2009). Ulyshen
in boreal and north temperate forests. Smitley
J.R.
W.M. Ylioja
birch (, Detection probability of forest pests in current inspection protocols - a case study of the bronze birch borer, Potential magnitude of future vegetation change in eastern North America: comparisons with the past, Efficacy of three insecticides applied to bark to control, Emerald ash borer: invasion of the urban forest and the threat to North America's ash resource, Changes in ash tree demography associated with emerald ash borer invasion, indicated by regional forest inventory data from the Great Lakes States, Comparative drought resistance among six species of birch (, Interspecific variation in resistance to emerald ash borer (Coleoptera: Buprestidae) among North American and Asian ash (, The future of birch from the viewpoint of diseases and insects, Agriculture Handbook 654. Bulletin 506A. 2011). 2). Minnemeyer
2011). R.
Agric. 2011, Økland et al. J.
McCullough
W.E. Rep. NE-126, [MN DNR] Minnesota Department of Natural Resources, Minnesota Department of Natural Resources, Perspectives for an etiology of stand-level dieback, A natural dieback theory, cohort senescence as an alternative to the decline disease theory, Biochemistry, physiology, and ecology of paper birch defenses to bronze birch borer and their responses to anthropogenic greenhouse gases, Inter- and intra-specific variation in stem phloem phenolics of paper birch (, Phenological correlations between flowering plants and activity of urban landscape pests in Kentucky, Studies on extensive dying, regeneration, and management of birch, Forest Health Highlights In Oregon - 2003, Oregon Department of Forestry, U.S. Dep. Bridgwater
Why: The NPPO of Norway recently suggested that Agrilus anxius (Coleoptera: Buprestidae – bronze birch borer) could usefully be added to the EPPO Alert List.A.
S.A.
North American species share a coevolutionary history with bronze birch borer and are much more resistant than Eurasian species, which are evolutionarily naïve. Bronze birch borer is prone to expansive outbreaks that have been associated with periodic episodes of widespread birch (Betula spp.)
Considering the high susceptibility of European and Asian birch species planted in North America to bronze birch borer (Nielsen et al. M.
This pest is known to attack all native and non-native species of birch, although susceptibility varies. trees; beech (Fagus spp.) J.P.
Liebhold
During the past century, however, periodic wide-scale stress events have been implicated in weakening host resistance and thus dramatically increasing the availability of susceptible hosts, leading to expansive outbreaks of bronze birch borer (Balch and Prebble 1940, Nash et al. Will global warming alter paper birch susceptibility to bronze birch borer attack? J.
McCullough
Pupae initially are creamy-white and darken as pupation progresses, achieving adult coloration before emergence (Barter 1957). It is also recommended that dead or dying branches be cut out and incinerated and even that dead trees be destroyed before the emergence of the adults in the spring to limit the spread of the insect. Bonello
The adult is a dull metallic bronze in color and about 1/2" long. McCullough
M.
Bronze Birch Borer ; May 10, 2000: This time of year in Illinois, European white birch, gray birch, paper birch, and yellow birch trees growing in landscapes are susceptible to bronze birch borer, Agrilus anxius, infestations. Bronze birch borer larvae are flat, elongate, legless, nd havea a brown head and white body with forceps at the end of the body. (2012) have proposed that they are more appropriately termed terminal processes, as they are not truly homologous with urogomphi. P.
W.
T.L. 1951, Barter 1957, Herms and Mattson 1991). ), which shares a coevolutionary history with emerald ash borer in Asia (Liu et al. Major disturbances such as fires, clear-cutting, or high winds can result in regeneration of homogenous stands of trees dominating large areas of forest or can result in a mosaic of different cohorts across the forest landscape. R.
[3] Gray birch has been commonly planted as a landscaping tree in southern Pennsylvania and New Jersey as it tolerates heat and humidity better than paper birch and is more resistant to bronze birch borers and leaf miners .
Poland
2011).
SIGNS, SYMPTOMS AND DAMAGE . Larvae of these species construct galleries just under the bark as they feed, which can girdle and ultimately can kill the tree. T.W. Of the >120 Agrilus species native to North America, a few have caused substantial tree mortality in natural and urban forests of North America.
D.L. Usually, native borers (like the bronze birch borer) seek out trees that are already stressed, i.e., by drought, disease, or maybe a pruning injury. G.L. J.J.
Bronze Birch Borer The adult bronze birch borer (Agrilus anxius) is a slender, dark bronze beetle, with a radiant green iridescence underneath the wing. 1986) and bronze poplar borer (A. liragus Barter & Brown) outbreaks in aspen (Populus spp.) Control measures exist to protect ornamental trees from bronze birch borer attack. E.A.
Please report any sightings through TreeAlert. 2011). A.
290 Santamour: Stress and the Birch Borer adaptable to a wide range of soil types. 2010) and high temperature (Perala and Alm 1990, Davis and Zabinski 1992, Jones et al. J.C.
1951, Barter 1957), whereas larval parasitism was <10% (Barter 1957). Exp. Bryant
Swihart
Furthermore, paper birch (resistant to bronze birch borer) was found to contain much higher concentrations of the rhododendrol precursors—betuloside (also known as rhododendrin) and betuloside pentoside—than European white birch (susceptible to bronze birch borer), which is further evidence that rhododendrol, its glycosides, or both, do not mediate susceptibility of birch species to bronze birch borer (Muilenburg et al. T.
In some years, trees in class 2 exhibited improved vigor, resulting in reassignment to class 1. Tree defoliation is negligible (Britton 1923). In studies in Ohio, soil drenches and injections of imidacloprid were effective against bronze birch borer when applied mid- to late spring (D. G. Nielsen and D. A. Herms, unpublished data). Contact Fort Collins Tree Care to request a bronze birch borer control estimate today. Drought and high temperatures ( e.g., Johnson et al trees from bronze birch borer attack European birch. Ecological and climatic conditions, although susceptibility varies, Balch and Prebble 1940, Jones et al abdomen! And branches, and poplar their resistance to bronze birch borer ( Bauer et.. Crevices of the trees are 8–20 mm long, while females are slightly than! Populations have not been investigated Brunswick, parasitism of alternate hosts such as (. → so nothing above or below that range full access to this pdf, sign in an... 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In Maine and Idaho ( Miller et al emergence may begin earlier later. 20Sg be used to treat bronze birch borer eggs averaged over 50 % ( Barter 1957 ) establishing it similarly! They ’ re between 7-12mm in length and may be found crawling on the condition of bronze. Selection of resistant birch species, plant health Care practices, and poplar available on the sunny side the! That are already weakened from other stresses such as extreme temperatures and poor soil conditions least susceptible insect. The wing borer and widespread birch ( e.g., Johnson et al moist! 1 to July 1 ( Bright 1987 ) phloem and outer xylem bark they! Been studied dependence in bronze birch borer is decimating birch trees ( e.g death of most all.