不同寄主来源种群花绒寄甲成虫对桃红颈天牛幼虫虫粪的行为趋性和种群控制效果

【目的】桃红颈天牛Aromia bungii是危害桃、杏、李、樱桃的主要蛀干害虫,花绒寄甲Dastarcus helophoroides是一种能有效防治多种天牛类林木钻蛀害虫的重要天敌昆虫。本研究通过比较不同寄主来源种群花绒寄甲对桃红颈天牛幼虫虫粪的行为反应和对幼虫控制能力的差异,旨在筛选能够有效防治桃红颈天牛的花绒寄甲种群。【方法】采用Y型嗅觉仪测定了6个不同寄主来源种群花绒寄甲成虫对桃红颈天牛幼虫虫粪的行为趋性;采用纱网罩受害原木模拟自然条件,释放不同种群花绒寄甲成虫测定了其对桃红颈天牛的致死效果。【结果】行为趋性结果表明,源自松褐天牛和云斑天牛的花绒寄甲种群对桃红颈天牛幼虫虫粪表现出明显的正趋向反应,而源自光肩星天牛、星天牛、锈色粒肩天牛和栗山天牛这4个种群的花绒寄甲对桃红颈天牛幼虫虫粪均未表现出明显的趋向反应。持续2年的寄生控制实验表明,源自光肩星天牛的花绒寄甲种群致死效果较好,天牛死亡率为52.86%±5.97%,源自松褐天牛、云斑天牛、栗山天牛和锈色粒肩天牛的花绒寄甲种群控制效果依次降低,天牛死亡率分别为35.14%±5.55%,32.88%±5.50%,26.09%±5.29%和10.94%±3.90%,源自星天牛的花绒寄甲种群未显示出对桃红颈天牛的控制作用。【结论】利用花绒寄甲防治桃红颈天牛时,应选择源自松褐天牛、云斑天牛或光肩星天牛的花绒寄甲种群。     

花绒寄甲辨别光肩星天牛蛀食不同树木所产生虫粪的挥发性化学信号

光肩星天牛(Anoplophora glabripennis)危害多种阔叶树种,曾对"三北"防护林造成重大灾害。花绒寄甲(Dastarcus helophoroides)对光肩星天牛取食不同寄主树如杨树、柳树、榆树和槭树后排出的虫粪表现出不同的趋向性,但对槭树的虫粪未表现出趋向性。为了阐明花绒寄甲成虫差异性趋向选择机制,我们采用动态顶空吸附技术收集不同寄主树的虫粪挥发物,利用气相色谱、固相微萃取-气相色谱-质联仪对虫粪中单萜、倍半萜进行定性定量分析。结果表明,萜烯类是虫粪挥发物的主要成分,且源自不同寄主树木虫粪的萜烯释放量相差显著。检测到的所有化合物中,只有α-古巴烯在源于复叶槭的光肩星天牛虫粪中含量极微,而在源于其他5种寄主树的虫粪中含量均较大。在进一步的Y型嗅觉仪生测实验中,α-古巴烯能够显著地吸引花绒寄甲。α-古巴烯可能是花绒寄甲辨别取食不同寄主树的光肩星天牛虫粪的重要信号化合物。     

花绒坚甲生物学特性及应用研究

<正> 花绒坚甲Dastarcus longulus Sharp属鞘翅目,坚甲虫科。我国北京、辽宁、山西、陕西、湖北、江苏等省市都有分布,国外分布于日本。可寄生光肩星天牛、刺角天牛、云斑天牛、桑天牛和松褐天牛等。在北京市是光肩星天牛的主要寄生性天敌,从5月至9月都有幼虫寄生,自然寄生率最高可达到60％,对开展生物防治光肩星天牛非常重要。为了进一步弄清它的生物学特性及应用价值,我们于1979～1985年进行了一系列室内外观察和研究。     

大斑啄木鸟对光肩星天牛幼虫捕食的功能反应和数值反应

光肩星天牛Anoplophora glabripennis（Motsch．）是我国重要林木蛀干害虫,造成了巨大的经济损失（张星耀、骆有庆,2003）。大斑啄木鸟Picoides major（L．）是林业蛀干类害虫的重要天敌,关于啄木鸟对蛀干类害虫的控制作用国内已有一些报道,     

利用管氏肿腿蜂防治光肩星天牛技术研究

光肩星天牛Anoplophora glabripennis是我国重大的森林害虫,对我国造林绿化和林业生态工程建设造成了严重危害。由于其为蛀干害虫,隐蔽性生活,难以防治。利用天敌开展生物防治是控制天牛的重要措施,作者研究探讨了利用管氏肿腿蜂Sclerodermus guani防治光肩星天牛技术。测定了管氏肿腿蜂对光肩星天牛1～3龄幼虫的室内控制作用,研究了林间防治防治技术。结果表明,在室内试验条件下,管氏肿腿蜂由于是抑性外寄生性,其产卵之前的刺蛰可造成天牛幼虫直接死亡,对1、2、3龄幼虫的平均致死率分别为100％、92．10％和87．29％;可寄生3龄天牛幼虫。在管氏肿腿蜂防治光肩星天牛小幼虫的林间试验中,管氏肿腿蜂对光肩星天牛小幼虫的致死率为27．79％-37．87％,平均为32．51％,放蜂比例以蜂虫比8-10：1的寄生率最高。     

栗山天牛天敌花绒寄甲在栎林中的种群保持机制

花绒寄甲(Dastarcus helophoroides)(鞘翅目:寄甲科Bothrideridae)是寄生栗山天牛(Massicus raddei)中老龄幼虫和蛹的重要天敌,但其寄主栗山天牛世代周期长(3年1代)、发育比较整齐,不利于寄生性天敌种群数量的稳定.为了解利用花绒寄甲防治栗山天牛后,其种群能否在栎树林间长期保持较高的种群数量,达到持续控制栗山天牛的防治效果,调查研究了花绒寄甲在栎树林间的转主寄主和种群保持机制.结果表明,在东北辽东栎树干和树枝上除了栗山天牛外,还有其他8种天牛危害:双簇天牛(Moechotypa diphysis)、四点象天牛(Mesosa myops)、中华薄翅锯天牛(Megopis sinica)、锯天牛(Prionus insularis)、双带粒翅天牛(Lamiomimus gottschei)、八字绿虎天牛(Chlorophorus tohokensis)、日本绿虎天牛(C.japonicus)和拟蜡天牛(Stenygrinumquadrinotatum).其中以栗山天牛、双簇天牛、四点象天牛和拟蜡天牛数量较多,而花绒寄甲在辽东栎树干上的垂直分布与栗山天牛、双簇天牛和四点象天牛的垂直分布重叠较多.室内研究表明,花绒寄甲对四点象天牛老熟幼虫的寄生率达到26.67％,对蛹的寄生率达到了43.33％;对双簇天牛老熟幼虫的寄生率达到20.00％,对蛹的寄生率为6.67％.对双簇天牛和四点象天牛在林间的生活史调查和研究发现,花绒寄甲可寄生的这两种天牛的中老龄幼虫和蛹,在花绒寄甲不适宜寄生的栗山天牛幼龄幼虫期大量存在,表明双簇天牛和四点象天牛是花绒寄甲在栎树林中的主要转主寄主.由于这些转主寄主的存在,花绒寄甲在不利于其寄生的栗山天牛卵期、幼龄幼虫期可转移寄生这些寄主,从而在栗山天牛危害的栎树林间保持了较高的种群数量,达到对栗山天牛长期而有效的持续控制效果.     

林间花斑花绒寄甲幼虫种群动态及空间分布格局

花绒寄甲Dastarcus helophoroides Fairmaire以幼虫寄生松褐天牛Monochamus alternatus等天牛类害虫,掌握其幼虫时空动态和空间分布格局,有助于制定花绒寄甲的生物防治利用策略。通过对江西马尾松林花绒寄甲幼虫种群数量的调查,应用聚集度指标和回归分析等,对林间花绒寄甲幼虫种群动态、水平分布和垂直分布进行了研究。结果表明,林间花绒寄甲幼虫种群动态呈现极明显的波动性,全年数量动态有2个高峰期,其中主高峰期是4月份,占全年幼虫总数量的30%左右,是幼虫的主要寄生期,次高峰期是8月份。花绒寄甲幼虫水平空间分布为聚集分布,分布的基本成分是个体群,聚集的原因可能是花绒寄甲自身习性或与寄主天牛、环境因素共同作用所致。不同时间段,花绒寄甲幼虫的垂直分布情况不同,3-7月,花绒寄甲幼虫主要分布在枯死木的中上部,其中上段幼虫数占总数的50%以上,而在8-12月,花绒寄甲幼虫主要分布在枯死木的中段,占总数的50%左右。另外,调查显示,花绒寄甲幼虫寄生数量在释放过该天敌的松林要远高于未释放过的松林,特别是在马尾松纯林,其幼虫种群数量更高,这说明通过人工释放（江西在3月释放成虫）,能增加林间天敌花绒寄甲种群数量、降低松褐天牛种群数量,有助于松材线虫病的控制。花绒寄甲幼虫种群时空、水平、垂直三维空间分布结果可为该天敌的保护、人工释放和有效利用提供科学依据。     

环境温度和体型大小对花绒寄甲成虫死亡率及产卵量的影响

[目的]花绒寄甲Dastarcus helophoroides是天牛类林木蛀干害虫的主要天敌昆虫,为提升花绒寄甲的人工繁育技术和繁育质量,在不同环境温度下,测试了不同体型大小的花绒寄甲对成虫死亡率和产卵量的影响.[方法]按成虫体型大小将花绒寄甲分成较大、较小和中等3组,根据前期不同温度下的饲养经验,分别测试成虫在20、24和28℃下的存活率和产卵量.[结果]体型相同的个体随环境温度升高死亡率增加;20℃时体型小的死亡率高,24℃和28℃各组死亡率无显著性差异;中等个体组在24℃和28℃下的产卵量大于在20℃下的产卵量;同一温度条件下,体型显著影响雌虫的产卵量,体型大者产卵量高.[结论]体型大小对成虫死亡率影响不明显,但对产卵量有较大影响.     

栗山天牛及其天敌花绒寄甲空间分布的地统计学分析

本文用地统计学的方法研究了栗山天牛及其天敌花绒寄甲的空间分布规律,结果表明:栗山天牛与花绒寄甲均呈聚集性分布,而且栗山天牛分布较多的样地,花绒寄甲也较多,花绒寄甲与栗山天牛有较强的跟随效应。栗山天牛与花绒寄甲的空间分布模型为球状+指数套合模型。栗山天牛和花绒寄甲空间分布在四个方向的变程均在100 m左右,而且在四个方向均比较集中。栗山天牛在东西方向聚集度最高,超过了0.8,而花绒寄甲在南北方向聚集度最高,2008年达到0.8452,2009年达到0.7230。研究还表明,2008年人工释放花绒寄甲后,其成虫在林间逐渐扩散,聚集度下降。     

赣南花绒寄甲松树林间自然寄生率调查研究

花绒寄甲Dastarcus helophoroides(Fairmaire)是松褐天牛Monochamus alternatus的有效寄生性天敌,为了解花绒寄甲在江西赣南苏区对松褐天牛种群数量的控制作用,开展了花绒寄甲在赣南松树林内自然分布、寄生率及松褐天牛种群情况的调查。结果表明,花绒寄甲在赣南松树林内分布广泛,对松褐天牛的自然寄生率为2.56%-22.41%,平均寄生率为11.74%,其中马尾松纯林的寄生率最高(14.81%),其次马尾松混交林(10.95%),湿地松纯林寄生率最低(2.56%),前两项差异不显著,后者与前两者均差异显著(P0.05);花绒寄甲的种群数量动态与其寄主松褐天牛的种群数量动态是一致的,呈正相关关系(R2=0.8399),花绒寄甲在野外主要以1-2头幼虫寄生1头松褐天牛幼虫的寄生方式营寄生生活(占79.10%)。因此在赣南松林中,花绒寄甲种群数量较低,必须大量补充人工繁育的寄甲,才能达到控制松褐天牛防治松材线虫病的目的。     

(R)‐(+)‐limonene,kairomone for Dastarcus helophoroides,a natural enemy of longhorned beetles

1 Chemical cues involved in host location by Dastarcus helophoroides (Fairmaire) (Coleoptera: Bothrideridae), a parasitoid of Anoplophora glabripennis Motschulsky, Monochamus alternatus Hope, Massicus raddei (Blessig), Apriona germari (Hope), Apriona swainsoni (Hope) and Batocera horsfielde (Hope) in the family Cerambycidae, were investigated in a Y‐tube olfactometer. Responses of D. helophoroides adults toward odour sources from their host (M. raddei) and host tree (Quercus mongolicus Fisch. ex. Turcz.) were tested in either no‐choice or two‐way choice tests. Wood with larval tunnels and larvae frass were attractive to D. helophoroides. Both sexes showed attraction to wood with larval tunnels. 2 Volatile chemicals emitted from wood with larval tunnels and larval frass were collected on Porapak Q and analyzed by gas chromatography‐mass spectrometry. Several compounds identified from these sources, including α‐pinene, β‐pinene, Δ‐3‐carene, limonene and β‐myrcene, were tested against D. helophoroides in the same Y‐tube olfactometer. 3 The result showed that D. helophoroides adults were attracted to (R)‐(+)‐limonene, with or without the background odour from uninfested fresh wood. This may suggest that (R)‐(+)‐limonene is an important kairomone for this parasitic beetle. 4 Dose‐dependent response of D. helophoroides adults to (R)‐(+)‐limonene indicated that D. helophoroides adults showed significant attraction to (R)‐(+)‐limonene when release rates exceeded 2.08 μg/h in Y‐tube olfactometer tests. Moreover, significantly more A. glabripennis larvae were parasitized by D. helophoroides in the presence of R‐(+)‐limonene, relative to the control in cage experiments.     

Field evaluations of systemic insecticides for control of Anoplophora glabripennis (Coleoptera: Cerambycidae) in China

Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae), a pest native to China and Korea, was discovered in North America in 1996. Currently, the only reliable strategy available for eradication and control is to cut and chip all infested trees. We evaluated various doses of the systemic insecticides azadirachtin, emamectin benzoate, imidacloprid, and thiacloprid for control of A. glabripennis in naturally infested elms (Ulmus spp.), poplars (Populus spp.), and willows (Salix spp. ) in China between 2000 and 2002. Significantly more dead A. glabripennis adults were found beneath elm and poplar trees treated with imidacloprid (in 2000 and 2001) or thiacloprid (in 2001) and beneath willow trees injected with imidacloprid or thiacloprid (in 2002) compared with control trees. In 2000, 4 mo after injection, the density of live A. glabripennis was significantly reduced in poplar trees treated with imidacloprid (90%) and in willow trees treated with imidacloprid (83%) or emamectin benzoate (71%) compared with controls. In 2001, 9 mo after injection, the density of live A. glabripennis was significantly reduced in poplar (76%) and willow (45%) trees treated with imidacloprid compared with control trees. Similarly, percentage mortality of all life stages of A. glabripennis feeding within trees was significantly higher on poplar trees 4 mo after injection with imidacloprid (64%) in 2000 and on elms (55%) and poplars (63%) 9 mo after injection with imidacloprid in 2001 compared with control trees. Imidacloprid residue levels in leaves and twigs collected at various times from 1 d to 9 mo after injection ranged from 0.27 to 0.46 ppm. Injecting A. glabripennis-infested trees with imidacloprid can result in significant mortality of adults during maturation feeding on leaves and twigs and of all life stages feeding within infested trees. Imidacloprid is translocated rapidly in infested trees and is persistent at lethal levels for several months. Although, injection with imidacloprid does not provide complete control of A. glabripennis, systemic insecticides may prove useful as part of an integrated eradication or management program.     

接种量对花绒寄甲繁殖的影响

释放花绒寄甲防治天牛已成为重要手段,而繁殖花绒寄甲时,接种花绒寄甲幼虫到大麦虫蛹体时,控制合适的接种量是提高花绒寄甲繁殖数量和质量的关键技术。本研究通过在替代寄主上人工接种不同数量的花绒寄甲幼虫,观察其发育情况及其子代数量、质量等指标,明确最佳接种量。结果表明：随着接种量的增加,花绒寄甲幼虫历期和蛹历期明显缩短,其中接种4头/个和6头/个,幼虫历期为13 d,蛹历期为33 d,而接种14头/个和16头/个时,幼虫历期短于12 d,蛹历期明显缩短为28~29 d。花绒寄甲结茧数随接种量增加而增加,接种数为16头/个时,结茧数最多,接近7个。花绒寄甲结茧率随着接种量增多而降低,4头/个时,结茧率最高为72.3%。接种量对花绒寄甲子代个体数量和大小均有显著影响,其中接种8头/个时,羽化数平均为4.3头,显著高于接种4头/个（羽化数平均为2.8头）,明显低于接种16头/个(羽化数平均为6.9头)。接种量为4头/个和6头/个时,子代成虫个体最大,单头重平均每头可达0.035 g,接种量为8头/个时,成虫单头重平均每头0.032 g左右,接种量达到16头/个时,单头重最轻,为0.023 g。对花绒寄甲羽化率无显著影响,7个处理下子代羽化率均较高,平均在94.4%~100%。接种量越少,更利于花绒寄甲的生长发育,当接种量为4头/个时,花绒寄甲成虫发育最好,其子代个体最大,但子代数较少。因此,利用大麦虫蛹繁育花绒寄甲种虫时,最佳接种量为4头/个,而需要规模化繁育花绒寄甲作为天敌使用时,综合考虑子代数量和质量以及经济成本,最佳接种量为8头/个。     

外源海藻糖对花绒寄甲成虫存活和耐寒性的影响

【目的】探讨取食不同浓度外源海藻糖对室内饲养的花绒寄甲 Dastarcus helophoroides 成虫存活和耐寒性的影响。【方法】在室内分别用含3%, 6%和9%海藻糖的半人工饲料饲养花绒寄甲成虫,以取食不含海藻糖的半人工饲料的花绒寄甲成虫为对照组,统计饲养10周后的存活率,测定未经低温处理和10℃低温处理3 d的成虫过冷却点和含水量。【结果】取食含6%海藻糖的半人工饲料的花绒寄甲成虫存活率最高,为86.67%。不管是否经低温处理,取食含9%海藻糖的半人工饲料的成虫与取食含3%和6%海藻糖的半人工饲料的成虫以及不含海藻糖的半人工饲料的成虫(对照)相比,其过冷却点均最低,其中未经低温处理的成虫过冷却点为-19.30℃,而经低温处理的成虫过冷却点为-21.60℃。低温处理对取食不含海藻糖的半人工饲料的成虫的含水量有显著影响,而对取食含海藻糖的半人工饲料的成虫含水量无显著影响。【结论】外源海藻糖对花绒寄甲成虫的存活和过冷却点有显著影响,可以利用外源海藻糖提高室内饲养花绒寄甲成虫的存活率和耐寒性。     

人工光暗条件下花绒寄甲成虫活动行为节律

【目的】花绒寄甲 Dastarcus helophoroides (Fairmaire)是林木蛀干害虫重要的天敌昆虫,研究其行为活动昼夜节律,可以深入了解该虫的生物学特性、阐明其生活习性。【方法】采用室内（温度27±1℃、相对湿度65%±10%）条件下雌雄单头隔离饲养的方法,将该虫的行为活动分为移动、取食、饮水、木块处静息和木块外静息5种行为,每隔30 min记录一次,于2014年7月10-15日连续进行观察。【结果】移动和木块处静息行为存在明显的昼夜节律;移动行为主要发生在暗期,移动高峰发生在20:30-22:30和2:00-4:00之间,而在光期的6:00-16:30之间移动行为发生较少木块处静息行为主要发生在光期的9:30-16:30和暗期的0:00-1:30之间,而在20:30-23:00 的暗期中木块处静息行为发生较少。一天内,该虫发生取食和饮水行为均较少,两类行为主要发生在0:00-14:00之间。木块外静息行为主要发生在暗期的0:30-3:30和20:00-22:00之间。雌、雄成虫的各行为出现的时间和发生百分率无显著差异。【结论】花绒寄甲成虫活动行为受到光、暗条件的显著影响,移动行为主要发生在暗期,而各活动行为在雌、雄虫之间无显著性差异。     

Toxicity of ethanedinitrile to Anoplophora glabripennis (Coleoptera: Cerambycidae) larvae

The mortality of naked Anoplophora glabripennis Motschulsky (Coleoptera: Cerambycidae) larvae exposed to ethanedinitrile (cyanogen; C2N2) varied with temperature, time of exposure, and dose of ethanedinitrile. The concentration x time (Ct) product of ethanedinitrile over a range of temperatures (4.4, 10.1, 15.6, and 20.1 degrees C) decreased with increasing temperature, for both 3- and 6-h exposures. The Ct products varied with time of exposure at different temperatures. The variations in mortality at different temperatures are described with a slope ratio (Y = [slope]6h/ [slope]3h). At different temperatures, the concentration of ethanedinitrile and the duration of exposure play different roles in killing A. glabripennis larvae. These results suggest the control of A. glabripennis larvae within wood is achievable.     

Laboratory evaluation of the toxicity of systemic insecticides for Control of Anoplophora glabripennis and Plectrodera scalator (Coleoptera: Cerambycidae)

Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae) is one of the most serious nonnative invasive forest insects discovered in North America in recent years. A. glabripennis is regulated by federal quarantines in the United States and Canada and is the subject of eradication programs that involve locating, cutting, and chipping all infested trees. Other control methods are needed to aid in eradication and to form an integrated management program in the event eradication fails. We conducted laboratory bioassays to determine the toxicity of two systemic insecticides, azadirachtin and imidacloprid, for potential control of A. glabripennis and the cottonwood borer, Plectrodera scalator (F.) (Coleoptera: Cerambycidae), a closely related native cerambycid. Larvae of both cerambycid species were fed artificial diet with dilutions of azadirachtin or imidacloprid for 14 wk. Both insecticides exhibited strong antifeedant effects and some toxicity against A. glabripennis and P. scalator larvae. For A. glabripennis, the highest larval mortality at the end of the bioassay was 60% for larvae fed artificial diet treated with azadirachtin (50 ppm) or imidacloprid (1.6 ppm). For P. scalator, the highest larval mortality at the end of the bioassay was 100% for larvae fed artificial diet treated with azadirachtin (50 ppm) or imidacloprid (160 ppm). At 14 wk, the LC50 values for P. scalator were 1.58 and 1.78 ppm for azadirachtin and imidacloprid, respectively. Larvae of both species gained weight when fed diet treated with formulation blanks (inert ingredients) or the water control but lost weight when fed diet treated with increasing concentrations of either azadirachtin or imidacloprid. In a separate experiment, A. glabripennis adults were fed maple twigs treated with high and low concentrations of imidacloprid. A. glabripennis adult mortality reached 100% after 13 d on twigs treated with 150 ppm imidacloprid and after 20 d on twigs treated with 15 ppm imidacloprid. There was no visible feeding by A. glabripennis adults on twigs treated at the higher imidacloprid rate, and feeding was significantly reduced for adults placed on twigs treated at the low imidacloprid rate compared with adults on untreated twigs. In summary, imidacloprid and azadirachtin had both antifeedant and toxic effects against A. glabripennis and P. scalator and have potential for use in management programs. Based on our results, the delivery of high and sustained insecticide concentrations will be needed to overcome the antifeedant effects and lengthy lethal time for both larvae and adults exposed to these insecticides.     

转新型双价抗虫基因杨树对光肩星天牛及美国白蛾的抗性鉴定

为明确双价基因chitinase-BmkIT对鞘翅目害虫光肩星天牛及鳞翅目害虫美国白蛾的抗虫效果, 分别以转该双价基因的杨树茎干和叶片为材料,采用室内茎干接虫和叶片接虫方法鉴定其对光肩星天牛Anoplophora glabripennis和美国白蛾Hyphantria cunea幼虫的抗性。结果表明：转基因株系132-2,144-1,123-1对美国白蛾幼虫的致死作用和生长发育影响显著高于取食未转化叶片的处理（P＜0.05）,且对其后代产生了影响,表现为幼虫不能化蛹或化蛹后不能羽化或羽化不正常;但供试的8个转基因株系对光肩星天牛幼虫无明显的致死和生长抑制作用,表现为幼虫死亡率和体重均与取食非转化茎干幼虫无显著差异（P＞0.05）。结果提示,双价基因chitinase-BmkIT可作为杨树鳞翅目害虫的抗虫基因源,并且对延缓害虫抗性的产生具有一定的意义。     

Potential effect of Anoplophora glabripennis (Coleoptera: Cerambycidae) on urban trees in the United States

Anoplophora glabripennis Motschulsky, a wood borer native to Asia, was recently found in New York City and Chicago. In an attempt to eradicate these beetle populations, thousands of infested city trees have been removed. Field data from nine U.S. cities and national tree cover data were used to estimate the potential effects of A. glabripennis on urban resources through time. For the cities analyzed, the potential tree resources at risk to A. glabripennis attack based on host preferences, ranges from 12 to 61% of the city tree population, with an estimated value of $72 million-$2.3 billion per city. The corresponding canopy cover loss that would occur if all preferred host trees were killed ranges from 13-68%. The estimated maximum potential national urban impact of A. glabripennis is a loss of 34.9% of total canopy cover, 30.3% tree mortality (1.2 billion trees) and value loss of $669 billion.