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Nonnative, Noninvasive Woody Species Can Enhance Urban Landscape Biodiversity
Abstract and Figures
Increasingly, homeowner associations and municipalities are requiring a certain percentage of native trees and shrubs as part of any new landscape installation. These native species mandates make numerous claims as to the superiority of native plants over introduced species, including their ability to enhance ecosystem biodiversity. In contrast, nonnative trees and shrubs are labeled as harmful to biodiversity, primarily because they are improperly grouped with known invasive species. This review summarizes the current published science regarding the effects of native and nonnative woody species on urban landscape stability as measured by biodiversity of associated plants, birds, insects, reptiles, and mammals. The preponderance of studies demonstrate that parameters other than species nativity have the greatest influence on biodiversity of these groups. Rather than limiting tree and shrub selection lists to a narrow palette of native species, a more practical, science-based approach to enhancing urban landscape biodiversity is suggested.
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... These habitats support ecologically distinctive woody plant communities due to the degree in which they are designed and managed by individual homeowners and green industry professionals Richards et al., 1984). Common landscaping practices frequently involve the incorporation of a limited number of widely planted woody plants, but the diversity and composition of these ecosystems is tied to socioeconomics, landscaping trends in vogue, and nursery stock availability (Avolio et al., 2018;Chalker-Scott, 2015;Frank, 2014;Hope et al., 2003;Kendle and Rose, 2000;Raupp et al., 2006). As a result of these landscaping choices, some residential landscapes may be more likely to be attacked by phytophagous arthropods and plant pathogens (herein referred to as 'plant pests') than others. ...
... In addition to plant community diversity, plant species origin has also been hypothesized to influence the likelihood of a plant experiencing attack from either herbivores or pathogens (Gandhi and Herms, 2010;Keane and Crawley, 2002;Tallamy, 2004). Among the general public, native plant advocacy has gained widespread acceptance under the notion that native plants (versus exotic plants) are more likely to achieve sustainable landscaping goals due to their environmental adaptations, ability to conserve biodiversity, and reduced pest susceptibility (Chalker-Scott, 2015;Goodenough, 2010;Kendle and Rose, 2000). However, these relationships are not uniformly backed by the scientific literature (Chalker-Scott, 2015;Goodenough, 2010;Kendle and Rose, 2000). ...
... Among the general public, native plant advocacy has gained widespread acceptance under the notion that native plants (versus exotic plants) are more likely to achieve sustainable landscaping goals due to their environmental adaptations, ability to conserve biodiversity, and reduced pest susceptibility (Chalker-Scott, 2015;Goodenough, 2010;Kendle and Rose, 2000). However, these relationships are not uniformly backed by the scientific literature (Chalker-Scott, 2015;Goodenough, 2010;Kendle and Rose, 2000). Several ecological and evolutionary hypotheses offer predictions for how native and exotic plants and their herbivores and pathogens might interact based on their geographic origin (Martinson et al., 2020). ...
The woody plant communities found on residential properties constitute an integral component of cities’ green infrastructure and serve as a nexus between urban residents and the natural world. Despite this importance, residential landscapes are infrequently designed with principles of sustainability in mind, resulting in the extensive use of pesticides to suppress a diverse array of plant pests. In this study, we ask whether ecological theory can inform the sustainable design and management of woody plant communities on urban residential properties. The associational resistance and dilution effect hypotheses are analogous hypotheses, which posit that increasing biodiversity can inhibit the abundance of herbivores and pathogens, respectively. Importantly, theory suggests that it might not just be diversity that matters, but the right kind of diversity (i.e., community composition). Previous studies have demonstrated that herbivore abundance can be greater on native plants compared to exotic plants in residential landscapes. However, little is known regarding whether this translates into greater numbers of interventions to reduce damage associated with plant pests on native plants. To test these hypotheses, we utilized a multi-year, commercial plant health care program dataset. We examined, at the residential property scale, the relationships between woody plant diversity, the percentage of plants that were native, and pest management interventions. We found that the number of pest management interventions targeting phytophagous arthropods, but not plant pathogens, was negatively related to woody plant biodiversity. The percentage of native plants on a property had no relationship with the number of pest management interventions that occurred. Consequently, efforts to increase woody plant biodiversity in residential landscapes could result in increased phytophagous arthropod pest suppression, thereby reducing the need for pesticide applications and their associated adverse effects.
... The dominance of exotic species over native species throughout the city is consistent with other studies regarding the biodiversity of street trees in some European, North American, and Australian cities [70]. In some cases, exotic species have been preferred for their aesthetic appearance and economic value, but mostly for their higher resistance than native species in the restrictive street habitat [71][72][73][74]. However, using native species as street trees offers social, economic, and ecological benefits. ...
Street trees play a significant ecological role in modern urban ecosystems, but usually the selection criteria follow pragmatic reasons rather than bio-ecological suitability. Understanding the influence of such factors can be relevant, especially in cities having a certain complexity and area. This paper aims to analyze the variation in the distribution of street tree species within the city’s municipia of Rome to determine the influence of some factors in the selection process. Here, we have described the species of street trees in fourteen municipia of Rome, and we created five clusters of factors (bio-ecological, aesthetic, historical–cultural, health, and economic) that could constitute selection criteria for street trees. From our data analysis, the municipia of Rome were grouped into four main groups and the choice of trees was based on multiple selection criteria. Foliage type, longevity, fruit type, autochthony, and economic value were the primary criteria. In 90–100% of municipia, deciduous species dominate, with 50–150 years longevity, dry fruits, exotic species, and prices of <€500 per tree. Additionally, the flower type, allergenicity, size class, and cultural value were the secondary criteria. The biological and ecological characteristics of trees are key factors to consider in order to reduce the management of street trees and relative costs.
... As Red-crowned Parrots in South Texas were utilizing roughly 70% nonnative tree species for roosting, nesting, and feeding (Kiacz, personal communication), it was apparent that urban landscaping was a large driving force behind species occupancy, supporting previous observations and modeling outcomes [91,92]. While native trees are generally better for native birds in urban areas [99,101,102], nonnative trees in urban areas can be beneficial for native and nonnative birds alike [103], which appeared to be the case for the Red-crowned Parrots in our three US populations. ...
Many species of plants and animals thrive in urban habitats and stand to gain from the global trend in increased urbanization. One such species, the Red-crowned Parrot (Amazona viridigenalis), is endangered within its native range but seems to thrive in urban landscapes. While populations of endangered synanthropic species may be uncommon, they can act as genetic reservoirs and present us with unique conservation and research opportunities. We sought to determine the red-crowned parrot’s level of dependency on urban areas, as well as the climatic and anthropogenic drivers of their distribution throughout the United States. We built national level species distribution models for the USA using Maxent and correlated presence points derived from field work and citizen science databases to environmental variables for three Red-crowned Parrot populations: two naturalized (California and Florida) and one native (Texas). We found current occupancy to be 18,965 km2 throughout the three states. These three states also contained 39,429 km2 of high- and medium-quality habitats, which, if occupied, would represent a substantial increase in the species range. Suitable habitat showed a strong positive correlation with urbanization in areas where average monthly temperatures were at least 5 °C. The current and predicted distributions of Red-crowned Parrots were closely aligned with urban boundaries. We expected populations of Red-crowned Parrots and other synanthropic species to grow due to a combination of factors, namely, continued urbanization and the effects of climate change, which increase the size and connectivity of a suitable habitat. For some imperiled species, urban habitats could prove to be important bastions for their conservation.
... Lack of an appealing design discourages homeowners from pursing low-input landscapes, even when the separate components of the landscape are preferred (Hayden et al. 2015). When designed and installed correctly, speciesdiverse landscapes are aesthetically appealing, create plant communities that provide significant environmental services, and provide food and habitat for beneficial wildlife (Chalker-Scott 2018, 2015a, Cubino et al. 2020. ...
Despite global concerns regarding climate change, one thing remains constant: homeowners want gardens and landscapes that serve them functionally and aesthetically. The strong affinity homeowners have for their land can lead to excessive use of water and fertilizer. This literature review explores the relationships between homeowners and their residential landscapes and the efforts that can be made to address misuse and overuse of resources. Governmental organizations should work together with community groups, nursery and landscape associations, and university Extension faculty to understand homeowner desires and behaviors before instituting policies regarding resource use that are unpopular, resented, and ignored. Networking between the nursery industry and university Extension faculty and Master Gardener volunteers can provide educational opportunities for homeowners to understand and implement more sustainable landscape practices as well as showcasing ornamental landscape plants that can help meet both personal aesthetics and resource conservation goals.
... Tais espécies não precisam necessariamente serem excluídas dos planejamentos da arborização urbana, sendo que alguns indivíduos arbóreos exóticos apresentam um bom desempenho em relação às espécies nativas (ROLOFF et al., 2009;CHALKER-SCOTT, 2015). ...
As árvores exercem papel fundamental na qualidade ambiental e seus benefícios são indiscutíveis para a vida nas cidades. A expansão e crescimento urbanos sem fundamentação no planejamento arbóreo geram prejuízos na provisão desses serviços ambientais. O presente estudo teve como objetivo conhecer a composição florística e caracterizar a heterogeneidade e similaridade entre os indivíduos arbóreos de diferentes bairros do município de São Paulo. Os resultados indicaram alta similaridade de espécies entre bairros, conforme índice de Jaccard, e alta diversidade de espécies segundo índice de Shannon Weaver (H’) para os sete bairros avaliados na cidade de São Paulo, SP. Analisar a diversidade arbórea na cidade e planejar novos plantios atentando-se para a manutenção equilibrada de árvores da mesma espécie, gênero e família é primordial quando se almeja um planejamento arbóreo coerente e que considera a restauração dos ecossistemas degradados. PALAVRAS-CHAVE: Biodiversidade. Composição florística. Índices de diversidade.
... Generally, the use of native plant species is preferred for they are better acclimatized to the growing conditions, are able to live and thrive among pathogens, and require less maintenance and less fertilizer and water input (Gray & Sotir, 1996). However in the context of the inhospitable urban environment, in presence of abiotic stressors (heat, drought, infertile soil), and also in absence of invasion risks, introduced species are better adapters and generally exhibit better growth and development (Chalker-Scott, 2015;Roloff et al., 2009). In addition, introduced species are capable of fulfilling the ecosystem services and resilience in urban environments when native tree species are limited (Sjöman et al., 2016). ...
Industrialization and rapid urbanization have taken a toll on the environment. The increase in urban population has resulted in land areas being cleared for both residential and infrastructure development. The removal of plant coverage exposes the barren soil to heavy precipitation which subsequently leads to soil erosion and landslides. As part of sustainable development, a growing number of city councils have taken the initiative to integrate green spaces into urban areas. Urban forest parks and gardens are incorporated into the city blueprint to provide urbanites with recreational spaces and a chance to interact with nature. Moreover, the concept of urban forestry provides a balance between environmental degradation and development. Urban trees offer a wide range of services, namely, reduction of air and noise pollution, regulation of atmospheric temperature and mitigation of flood. The success of this concept relies primarily on the right selection of tree species and their rooting properties. Since Malaysia is located on the equator, the hot and humid weather had significantly reduced soil fertility due to chemical weathering and leaching. Hence, the use of phytoremediator or metal tolerant plants is recommended for they could ameliorate contaminated soils and at the same time provide aesthetic landscaping qualities.
... These are also among the best locations for the creation of micro-structures and microhabitats for wild species, such as bird tables, bird and bat boxes, amphibian refuge spots, arthropod boxes, small mammal houses, and even dead hood piles [126,157]. Nevertheless, all woody species play a considerable role in providing shelter for fungi, shade plants, smaller animals, such as birds and mammals (including bats), and insects [158]. Their upscaling, when considering the net of woody species of different home gardens and other trees in the landscape, creates a network of green corridors for many uncommon species in urban and rural areas [126,159]. ...
Home gardening has a long history that started when humans became sedentary, being traditionally considered an accessible source of food and medicinal plants to treat common illnesses. With trends towards urbanization and industrialization, particularly in the post-World War II period , the importance of home gardens as important spaces for growing food and medicinal plants reduced and they began to be increasingly seen as decorative and leisure spaces. However, the growing awareness of the negative impacts of agricultural intensification and urbanization for human health, food quality, ecosystem resilience, and biodiversity conservation motivated the emergence of new approaches concerning home gardens. Societies began to question the potential of nearby green infrastructures to human wellbeing, food provisioning, and the conservation of traditional varieties, as well as providers of important services, such as ecological corridors for wild species and carbon sinks. In this context. and to foster adaptive and resilient social-ecological systems , our supported viewpoint intends to be more than an exhaustive set of perceptions, but a reflection of ideas about the important contribution of home gardens to sustainable development. We envision these humble spaces strengthening social and ecological components, by providing a set of diversified and intermingled goods and services for an increasingly urban population.
... Rather than limiting planting palettes to native species (which may be poorly adapted to urban conditions), noninvasive exotic species adapted to these harsher conditions should be considered. A robust body of research supports the use of introduced trees and shrubs in residential and public landscapes in addition to appropriate native species (Chalker-Scott, 2018;2015b). Not only do they tolerate urban conditions, they provide habitat for wildlife just as effectively as native trees and shrubs. ...
Horticultural myths, found extensively in print and online resources, are passed along by uninformed gardeners, nursery staff, and landscape professionals. Occasionally myths are so compelling that they make their way into Extension publications, used by Master Gardeners as educational resources. In this article we deconstruct seven widespread gardening myths by way of reviewing research-based literature. We also provide scientifically sound alternatives to these gardening practices and products. Our hope is to arm Extension educators with the educational resources necessary to battle misinformation that ranges from the merely useless to that which is actively damaging to soils, plants, and the surrounding environment.
Biodiversity-sensitive cities can contribute to reconnect humans with nature and halt global biodiversity loss. Achieving biodiversity-sensitive cities is challenging, especially in regions threatened by growing urbanization. To inform urban management and planning in a global biodiversity hotspot, we conducted a multi-scale assessment of drivers of Neotropical birds in the capital city of Santiago de Chile. We investigate the influence of local and landscape variables on native bird species richness and abundance. We surveyed birds and vegetation in 449 sampling points distributed across the city. Native bird species richness was greater in areas with greater shrub and woody vegetation cover at the local scale. Native bird species richness was also greater with high vegetation density in the surrounding landscape and near to an urban boundary. Native birds were abundant in areas with large woody vegetation cover at both local and landscape scales, high vegetation density in the surrounding landscape, near to an urban park and near to an urban boundary. Additive effects of vegetation at different spatial scales suggest that combining local and landscape management, planning and design will be best to preserve native birds in a large city. Although near to the urban fringe native birds are species rich and abundant, local scale management of habitat encouraging shrub and tree planting and city-scale actions such as targeting high levels of vegetation (including woody cover) and providing a well-distributed network of urban parks will help sustain native birds across the city. Greening actions at local and landscape-scale will contribute to achieving biodiversity-sensitive cities, providing benefits for people and nature.
The indigenous or stingless bees are the major insects responsible for pollination of plants inBrazil. It is necessary to determine the species that occur in a region as well as their exploited floralresources, because these insects are under strong anthropogenic pressure which has caused a decrease inthe number of incident species in various areas. The objective of this study was to identify and collect thespecies of stingless bees in ESALQ-USP as well as their visited flowers and selecting species that can beused rationally. Seven species of stingless bees were found, whereas Tetragonisca angustula and Trigonaspinipes were the most frequent and abundant. Twenty-two species of plants visited by stingless bees,belonging to 18 families, were found. Montanoa grandifolia, Dombeya wallichii, Chamissoa acuminata andMacadamia integrifolia were the most visited. These plants have the potential to produce pollen and honeyfor the stingless bees, however, there is not much diversity of species and very few hollow trees that help inthe nesting of these individuals.
Key words: stingless bees, Atlantic Forest, diversity, survey.
Background and aims - The green infrastructure of rural settlements is represented by various land-uses which are of potential importance for the maintenance of biodiversity. Especially homegardens play an important part, but regardless of the knowledge that is available on the floras of urban environments, this feature has never been specifically quantified for South Africa, or any other southern Africa country. The aim of this study is to describe the contribution of homegardens towards the urban green infrastructure of a rural settlement in South Africa in terms of plant diversity and to provide a baseline for future research on urban floras of larger or culturally different urban areas. Methods - A grid provided 118 suitable sampling points for 20 × 20 m sample plots. Each sample plot consisted of five transects of twenty points each. At each of the 100 points the closest tree, shrub, forb and grass was recorded within a 0.5 m radius. For the purposes of this descriptive study, the frequency data was converted to presence-absence data. Key results - The four land-use types of Tlhakgameng is habitat for 460 species, in 302 genera and 96 plant families. Of these species 56% are alien to Thlakgameng. The two most dominant families were the Asteraceae and Poaceae and the most dominant genera Acacia and Eragrostis. The five most dominant species for the study area were all indigenous. A total of 27 South African endemic and eight Red List species were recorded from the settlement. Homegardens had the highest gamma diversity which was mainly alien species cultivated for their uses. Food plants and ornamentals made up the majority (68%) of the garden flora. Most of the alien species originate from Asia and the Americas, some of which are counted with the 41 declared invaders and weeds recorded from the study area. Conclusion - This study confirms that rural settlements, like urban environments, are floristically diverse. The results of this study revealed that homegardens have the highest species richness as compared to other types of land-use in a rural settlement. The majority of the species found in homegardens were cultivated horticultural floras, and indigenous and alien weeds. Homegardens also provide a refuge for endemic or threatened species. The various needs of households in Tlhakgameng seem to sustain the growth of a rich and diverse mixture of multipurpose species in homegardens.
Surveys were conducted from November 2004 to July 2005 in three habitat types in southwestern China. A total of 7,628 individuals of 123 bird species were recorded. By comparing our results to those of a previous study in the same area, we found that urbanization was likely responsible for decreasing species richness. Although some endangered water bird species vanished in the River habitats, there was higher species richness and diversity in this habitat than in other habitats, due to high nutrient availability. Additionally, small and isolated forest fragments in suburban areas failed to sustain high diversity, even though the heterogeneity of this environment favours local bird richness. Interestingly, we found signs of recovery of some vanishing native bird species, possibly due to a reduction of pesticide usage in Agricultural habitats.
In 1999, we surveyed breeding bird and plant communities along 54 streams in the Portland, Oregon, metropolitan region to link bird community metrics with structural and spatial characteristics of urban riparian areas. Canonical correspondence analysis produced two explanatory axes relating to vegetation and road density. Total and non-native bird abundance was higher in narrow forests. Native bird abundance was greater in narrow forests surrounded by undeveloped lands; native species richness and diversity were greater in less-developed areas. Native resident and short-distance-migrant abundance was higher in narrow forests, and diversity was positively associated with developed lands. Neotropical migrant abundance, richness, and diversity were greater in open-canopied areas with fewer roads. We examined spatial relationships by regressing bird variables on satellite-derived forest canopy cover, area of undeveloped lands, and street density in a series of 50-m buffers within a 500-m radius around study sites. Non-native bird abundance decreased with increasing canopy cover within 450 m, but most other relationships were strongest at smaller scales (50–100 m). Our results suggest that increasing urban canopy cover is the most valuable land management action for conserving native breeding birds. A hierarchical scheme for Neotropical migrant conservation might include increasing forest canopy within 450 m of streams to control non-native species and cowbirds; reducing street density within a 100-m radius of streams; and conserving or planting onsite native trees and shrubs.
Estructura de Comunidades Riparias de Aves en Portland, Oregon: Hábitat, Urbanización y Patrones de Escala Espacial
Resumen. Censamos las comunidades de aves reproductivas y plantas a lo largo de 54 arroyos en el área metropolitana de Portland, Oregon en 1999 para conectar medidas de comunidades de aves con características estructurales y espaciales de zonas riparias urbanas. Análisis de correspondencia canónica produjeron dos ejes explicativos relacionados con la vegetación y la densidad de carreteras. La abundancia total de aves y la de aves no nativas fueron mayores en bosques estrechos. La abundancia de aves nativas fue mayor en bosques estrechos rodeados por terrenos rurales y la riqueza y diversidad de especies fueron mayores en áreas menos desarrolladas. La abundancia de residentes nativas y migratorias de corta distancia fue mayor en bosques estrechos y su diversidad estuvo asociada positivamente con terrenos desarrollados. La abundancia, riqueza y diversidad de las migratorias neotropicales fueron mayores en áreas de dosel abierto y con pocas carreteras. Examinamos las relaciones espaciales mediante regresiones entre variables de aves y la cobertura del dosel derivada de imágenes satelitales, el área de terrenos sin desarrollar y la densidad de calles en una serie de áreas de 50 m de ancho en un radio de 500 m alrededor de los sitios de estudio. La abundancia de aves no nativas disminuyó con aumentos en la cobertura del dosel hasta 450 m, pero la mayoría de las demás relaciones fueron más fuertes a escalas menores (50–100 m). Nuestros resultados sugieren que el incremento de la cobertura del dosel en áreas urbanas es la estrategia de manejo más valiosa para conservar las aves nativas que se reproducen en el área. Un esquema jerárquico para la conservación de las migratorias neotropicales podría incluir aumentar la cobertura de bosque a menos de 450 m de los arroyos para controlar a las especies no nativas y a los Molothrus, reducir la densidad de calles dentro de un radio de 100 m alrededor de los arroyos y conservar o plantar árboles y arbustos nativos.
Bird composition of habitat fragments in urban areas is expected to be associated with adjacent landscape and with smaller-scale factors within fragments. This study investigated the bird assemblage of coastal oak (Quercus garryana) fragments in British Columbia, Canada adjacent to either coniferous forest or urban development. Effect of habitat type (oak, conifer, urban) and local habitat differences (tree volume, shrub cover, grass cover) on the composition of the bird assemblage was also determined. During the 2000 breeding season, birds were surveyed in a 50-m fixed-radius point count at stations along two transects within each habitat type. Bird assemblages were most different between forest and urban habitat. The bird composition of oak fragments fell in between. Within oak, most birds fell into one of three groupings: 1) associated with conifer trees within oak fragments adjacent to coniferous forest, 2) associated with oak, an invasive alien shrub (Cytisus scoparius), and grass, within oak fragments adjacent to coniferous forest, and 3) associated with snowberry (Symphoricarpos albus) in oak fragments adjacent to urbanization. The results indicate that the type of adjacent habitat and tree composition in oak fragments are significant factors associated with oak bird assemblages. Future shifts in species composition are possible as the region becomes more urbanized and coniferous trees encroach into remaining oak habitat.
Characteristics of stand of urban forest in Halifax, Nova Scotia, were analyzed with regards to tree-species composition and carbon sequestration. Older stands in residential and institutional neighbourhoods are dominated by non-native species of trees, thus limiting their usefulness in terms of protection of indigenous biodiversity values. These stands do, however, provide substanital ecosystem service in terms of carbon storage, because they are dominated by relatively large trees with an almost closed canopy (averaging 83% cover), and supporting a relatively large stand biomass (averaging 131 t/ha of above-ground tree biomass). In comparison, younger residential neighbourhoods have larger frequencies of native tree species, reflecting a recent trend to preserving some natural forest as buffer strips between properties. However, the proportion of native species of trees in the younger neighbourhoods is expected to decrease with time, because non-indigenous species are the strongly dominant choice among recent plantings by homeowners. Because of recent disturbance, urban forest in younger neighbourhoods has a relatively small biomass, but this should increase with succession. Natural-forest urban parks have a tree-species composition and stand structure that are similar to that of more remote, natural forests.
As a contribution for the implementation of the Master Plan of Machu Picchu Sanctuary (MPS), and supported by the Machu Picchu Program (a debt-for-nature swap between Finland and Peru), an inventory of the introduced plant species to this protected area was carried out. 208 no-native species were present in the area, 168 (80.8%) are useful species related with agro-ecosystems, gardens, and urban areas, while the remnant is either weed of Andean crops or naturalized species. 194 (92.3%) are non-invasive species, and apparently do not represent an actual threat to local biodiversity; 14 (7.7 %) of the species show some invasive tendencies, and four of them (1.9%) are spread to certain extent. Expansion of these species has occurred following corridors on the bottom of the Vilcanota’s zone, from the valleys of Cusco and La Convención, throughout disturbed areas (fire, agriculture, deforestation and/or cattle). Even though actual invasions have occurred for a handful of species, the process already requires a special management effort. The persistence of human-made disturbance regimes on natural ecosystems, and the high mobility of humans and products, increase the risk of new invasions. In order to prevent biodiversity loss, we propose an agenda or interrelated actions that includes: 1) prevention of new invasions, 2) research and monitoring of the dynamics of invasions both in natural areas and agro-ecosystems, 3) control of species that are affecting or arresting natural regeneration and growth of forests 4) control of species on archeological sites and 5) education and public awareness campaigns.
Blue spruce has locally been introduced to the forests in Central Europe. It was considered as a suitable substitute tree species in areas where afforestation with the native Norway spruce had not been successful, e.g. in areas heavily affected by air pollution. Young plantations of blue spruce were healthy, without serious insect damage. We studied the moth associates of blue spruce (Picea pungens) and Norway spruce {Picea abies) in the two distant regions (study areas) in Central Europe represented by West Carpathians (Veporské vrchy Mountains, Central Slovakia) and Hercynian Mountains (Děčínská vrchovina hills, north-west Bohemia) and addressed the questions as to whether ( 1 ) blue spruce and Norway spruce have similar moth fauna, (2) blue spruce planted in forests is a host for Coleotechnites piceaella (the moth already recorded in urban areas in Central Europe) and/or other moth species introduced from North America and (3) afforestation with the introduced blue spruce affects the diversity of Lepidoptera on the native Norway spruce. Over the growing season 2006 (West Carpathians) and 2007 (Hercynian Mountains) the beating method was used to collect caterpillars from the lower branches of blue spruce and Norway spruce. In addition, photoeclectors in the laboratory were used to record moth caterpillars (or hatched adults) overwintering on blue spruce and Norway spruce in the two study areas in March 2008. The sample branches of blue spruce and Norway spruce were placed into photoeclectors. Moth specimens that had emerged from photoeclectors were collected and identified. A total of 998 caterpillars (or hatched adults) were collected from blue spruce, and a total of 860 caterpillars (or hatched adults) were obtained from Norway spruce. The moth fauna on blue spruce was similar to that on Norway spruce. Blue spruce and Norway spruce were found to host equal number of moth species (31 species). All species recorded on blue spruce are developing on the native Norway spruce. Comparisons between blue spruce and Norway spruce revealed some differences in the species composition of caterpillar assemblages. A significantly higher abundance of needle spinning larvae (Batrachedridae, Gelechiidae and Tortricidae) and significantly lower abundance of bud-boring larvae (genus Argyresthia, Yponomeutidae) on blue spruce compared to Norway spruce, was the most pronounced difference. No moth species introduced from North America were recorded. Based on the results, the introduction of blue spruce to the Central European forests is only slightly influencing the diversity of moth assemblages on Norway spruce.