Distribution,spread, and impact of the invasive hornet Vespa velutina in South Korea

Hornets (Vespa spp) are top insect predators that can control pests, but their venomous stings and defensive behavior cause numerous human deaths throughout Asia. Hornets usually inhabit rural areas which reduces potential conflict with humans. In 2003, the invasive hornet, Vespa velutina, arrived in southern Korea (Yeongdo region) and became established. It is currently spreading northwards at a rate of 10–20 km per year. Despite originating in tropical/subtropical areas of Indo-China, its nesting biology and life cycle in South Korea are similar to those found throughout its native range, with mature colonies containing 1000–1200 adults. In 7 years, V. velutina has become the most abundant hornet species in Southern Korea by displacing native Vespa species such as V. simillima, which has a similar nesting biology. We also found a significant positive correlation between the abundance of V. velutina and the degree of urbanization, indicating that this invasive species was well adapted to urban environments. This was supported by our finding that 41% of emergency call-outs (119 Rescue Services) to deal with social wasps/hornet problems were due to V. velutina, which was twice as high as the number of calls about the next most abundant species. The rapid spread of V. velutina across southern Korea indicates that this species will continue to spread north-westward in the Korean peninsula and will become a major problem as more people and beekeepers come into contact with this aggressive invasive hornet.     

Experimental evidence for a delayed response of the above-ground vegetation and the seed bank to the invasion of an annual exotic plant in deciduous forests

Invasions by alien plants significantly affect native biodiversity and ecosystem functioning. We conducted a 5-year field experiment to investigate potential effects of the annual invasive plant Impatiens glandulifera on both the native above-ground vegetation and the soil seed bank in a deciduous forest in Switzerland. Eight years after the establishment of I. glandulifera, we set up plots in patches invaded by the alien plant, in plots from which the invasive plant had been manually removed and in plots which were not yet colonized by the invasive plant. We examined plant species richness, diversity and plant species composition in the above-ground vegetation and soil seed bank in all plots one year and five years after the initiation of the experiment. The 36 plots (3 plot types × 6 replicates × 2 sites) were equally distributed over two forest sites. Neither the native above-ground vegetation nor the soil seed bank was influenced by the presence of I. glandulifera one year after the start of the field experiment. After five years, however, plant species richness of both the above-ground vegetation and the soil seed bank was reduced by 25% and 30%, respectively, in plots invaded by the alien plant compared to plots from which I. glandulifera had been removed or uninvaded plots. Furthermore, plots invaded by the alien plant had a lower total seedling density (reduction by 60%) and an altered plant species composition in the soil seed bank compared to control plots. Our field experiment indicates that negative effects of the annual invasive plant on the native above-ground vegetation and soil seed bank of deciduous forests become visible with a delay of several years.     

Life table of cycad scale,Aulacaspis yasumatsui (Hemiptera: Diaspididae), reared on Cycas in Taiwan

Aulacaspis yasumatsui Takagi (Hemiptera: Diaspididae), an invasive scale insect, attacks different species of Cycas (Cycadales: Cycadaceae) in Taiwan. Development, survival and fecundity of A. yasumatsui were studied on Cycas taitungensis at 24 °C, 70 ± 10% RH, and a photoperiod of 12:12 (L:D) h under laboratory conditions. Data on the life history of A. yasumatsui were analyzed using the age-stage, two-sex life table, to address variable development rates among individuals and between sexes. The egg incubation time was 7.26 days for both females and males and female nymphal development duration was 28.65 days. The development duration of male nymphal stages + pupal stage was 19 days. The total pre-oviposition period (TPOP) was 35.92 days. The maximum longevity of female adults was 67 days and 1 day for males. The intrinsic rate of increase (r) was 0.100 day^-1, the finite rate of increase (λ) was 1.11 day^-1, the net reproduction rate (R_o) was 111.51 offspring /individual, and the mean generation time (T) was 47.24 day. Life table data can be used to project population growth, to design mass rearing programs and to establish management tactics to control insect pests.     

SAR studies directed toward the pyridine moiety of the sap-feeding insecticide sulfoxaflor (Isoclast™ active)

Sap-feeding insect pests constitute a major insect pest complex that includes a range of aphids, whiteflies, planthoppers and other insect species. Sulfoxaflor (Isoclast™ active), a new sulfoximine class insecticide, targets sap-feeding insect pests including those resistant to many other classes of insecticides. A structure activity relationship (SAR) investigation of the sulfoximine insecticides revealed the importance of a 3-pyridyl ring and a methyl substituent on the methylene bridge linking the pyridine and the sulfoximine moiety to achieving strong Myzus persicae activity. A more in depth QSAR investigation of pyridine ring substituents revealed a strong correlation with the calculated log octanol/water partition coefficient (S log P). Model development resulted in a highly predictive model for a set of 18 sulfoximines including sulfoxaflor. The model is consistent with and helps explain the highly optimized pyridine substitution pattern for sulfoxaflor.     

Barcoding forest insect pests in South Korea: Constructing a basic endemic species dataset

A total of 103 barcode (mitochondrial COI) sequences were newly provided for 77 forest insect pests from 66 genera belonging to Coleoptera, Hemiptera, and Lepidoptera. All 77 species had distinct COI sequences, revealing low intraspecific genetic divergence (< 1.20%) and high interspecific genetic divergence (> 7.30%). Among the 66 genera, 32 COI sequences of 25 species belonging to 16 genera were compared with 280 COI sequences of 117 species belonging to the same 16 genera archived in GenBank, showing that most species were clearly distinguished by barcode sequences. Based on these results, we conclude that a DNA barcode is effective for identifying forest insect pest species.     

The effect of semi-natural habitats on aphids and their natural enemies across spatial and temporal scales

Semi-natural habitats in agricultural landscapes are generally assumed to enhance the biological control of insect pests based on native beneficial insects, by providing alternative prey and hosts, resources and refuges for overwintering. We hypothesized that natural enemies of winter wheat aphids should arrive sooner in fields near semi-natural habitats. We compared aphid, hoverfly (larvae and eggs) and parasitized aphid (mummies) abundances in 54 winter wheat fields located in southern France from 2003 to 2007. Six surveys were recorded each spring and were split into the early period (defined as the period before the peak of aphid growth) and the late period (after the peak). The wheat fields differed by their surrounding landscape composition measured as the proportion of semi-natural habitats (woods, hedges and grasslands), at three different spatial scales: 200 m, 500 m, and 1200 m. Despite great variability in abundance data between years, the abundance of hoverflies appeared more sensitive to landscape composition than aphid abundance was. Early abundance for both aphids and hoverflies was positively related to wood cover, but not late abundance in spring. The abundance of hoverflies was positively related to hedge and grassland cover at all spatial scales and both periods considered. Aphid parasitism was higher near hedges at the small spatial scale late in the spring. Our results confirmed that higher proportions of semi-natural habitats in agricultural landscapes enhance the biological control of pests, but this effect depends on the spatial scale, the time period in the spring and the natural enemies considered.     

Frugivorous birds visit fruits of emerging alien shrub species more frequently than those of native shrub species in the South African Mediterranean climate region

We compared daily visitation frequency indices by 4 large (> 150 g), 7 medium-size (50–150 g), 5 small (30–50 g) and 8 and tiny (< 30 g) frugivorous bird species on fleshy fruits of two native shrubs (Olea europaea subsp. africana and Chrysanthemoides monilifera subsp. monilifera), two established alien shrubs (Solanum mauritianum and Lantana camara) and two emerging alien shrubs (Myoporum tenuifolium and Pittosporum undulatum) at nine different sites in the Cape Floristic Region. Large, medium-size and tiny birds as groups displayed significantly higher visitation frequency indices on fruits of both emerging alien shrub species than the other shrub species. Small birds as a group displayed insignificantly different visitation frequency indices on fruits of both emerging and established alien shrub species but significantly higher visitation frequency indices on fruits of both emerging and established alien shrub species than on fruits of the native shrub species. However, there were significant differences in foraging frequency indices of the bird species included within each of these body size groups on fruits of the different shrub species. Among the large birds, Columba guinea and among the medium size birds Sturnus vulgaris, Streptopelia senegalensis, Turdus olivaceus and Onychognathus morio all exhibited significantly higher visitation frequency indices on fruits of both emerging alien shrub species than on fruits of the other shrub species. These findings indicate that alien plant control measures should be focused on eradicating localised populations of emerging aliens to limit preferential consumption of their fruits by birds and consequent dispersal of their seeds that germinate readily into natural areas.     

Beef or grasshopper hamburgers: The ecological implications of choosing one over the other

Both the means by which we produce our food and our eating habits influence some of the most important environmental problems of our planet. The most exploited livestock for the past 50 years has been cattle, which are fed primarily on maize to increase production. However, this combination of maize and cattle is inefficient in ecological terms. Producing and consuming proteins from animals with more efficient biomass and energy conversions could help to solve certain environmental problems. For instance, insects that are considered pests in agricultural systems — including, specifically, the Orthoptera species — may be excellent candidates as protein sources. This work analyses the feed conversion ratio (FCR) of the three types of livestock that are most widely bred worldwide: cattle, pigs, and poultry. It then compares these results with those of potential minilivestock from the Orthoptera species that are more abundant in agroecosystems. Based on the calculated FCRs (cow:pork:poultry:grasshopper pests and insects grown on farms; 10:6:2:4:1.7), we project that reducing beef production by half could significantly lower greenhouse gas emissions and the maize sowing hectares destined for feed (2.1–2.9 × 10⁷ ha), while simultaneously releasing maize for human consumption. Additionally, consuming insect-based protein could reduce pollution problems by decreasing insecticide use (by at least 7 × 10⁷ l). Though a comprehensive solution to current environmental problems (e.g. global warming), will require coordinated global effort (e.g. to replace fossil fuels), there is one way that everyone can contribute: eating grasshopper burgers instead of beef burgers.     

The importance of relative humidity and trophic resources in governing ecological niche of the invasive carabid beetle Merizodus soledadinus in the Kerguelen archipelago

Comprehensive studies to identify species-specific drivers of survival to environmental stress, reproduction, growth, and recruitment are vital to gaining a better understanding of the main ecological factors shaping species habitat distribution and dispersal routes. The present study performed a field-based assessment of habitat distribution in the invasive carabid beetle Merizodus soledadinus for the Kerguelen archipelago. The results emphasised humid habitats as a key element of the insect’s realised niche. In addition, insects faced food and water stress during dispersal events. We evaluated quantitatively how water availability and trophic resources governed the spatial distribution of this invasive predatory insect at Îles Kerguelen. Food and water stress survival durations [in 100%, 70%, and 30% relative humidity (RH) conditions] and changes in a set of primary metabolic compounds (metabolomics) were determined. Adult M. soledadinus supplied with water ad libitum were highly tolerant to prolonged starvation (LT₅₀ = 51.7 ± 6.2 d). However, food-deprived insect survival decreased rapidly in moderate (70% RH, LT₅₀ = 30.37 ± 1.39 h) and low (30% RH, LT₅₀ = 13.03 ± 0.48 h) RH conditions. Consistently, body water content decreased rapidly in insects exposed to 70% and 30% RH. Metabolic variation evidenced the effects of food deprivation in control insects (exposed to 100% RH), which exhibited a progressive decline of most glycolytic sugars and tricarboxylic acid cycle intermediates. Most metabolite levels were elevated levels during the first few hours of exposure to 30% and 70% RH. Augmented alanine and lactate levels suggested a shift to anaerobic metabolism. Simultaneously, peaks in threonine and glycolytic sugars pointed to metabolic disruption and a progressive physiological breakdown in dehydrating individuals. Overall, the results of our study indicate that the geographic distribution of M. soledadinus populations is highly dependent on habitat RH and water accessibility.     

Distribution and management of invasive alien plant species in protected areas in Central Europe

Protected areas play a key role in biodiversity conservation, yet they face numerous pressures including the spread of invasive alien species (IAS). We designed a structured online survey to investigate the distribution and management of 53 invasive alien plant species in large protected areas, i.e. national parks and biosphere reserves, in eight Central European countries. We contacted 93 protected areas management authorities, of which 46 replied. In 44 protected areas (96% of those responding), at least one IAS was present, and in 37 protected areas (80%) IAS were managed. On average, 11.2 ± 6.9 IAS were present per protected area and 4.3 ± 3.4 (41%) of these were managed. A one-way ANOVA showed no significant difference in the number of IAS present or managed between the different protected area designations (national parks, biosphere reserves). Similarly, neither the size nor the founding year of the protected area influenced the number of IAS present or managed. Thirty-one species (58%) were managed in at least one protected area. The most widely managed species were Fallopia japonica (23 protected areas), Heracleum mantegazzianum (20), and Impatiens glandulifera (16). The amount of financial resources devoted to IAS management was rather low, corresponding to 3.1 ± 4.4% of the total budget for natural resources management of the protected areas. We conclude that a lack of dedicated funding for IAS management in most protected areas and a lack of coordinated response between protected areas currently limit the effectiveness of the IAS management. In particular, an increased exchange of expertise between protected areas, and the development of minimum standards for IAS surveillance and management are pivotal. In addition, documenting best practice examples and synthesizing lessons learned in IAS management are urgently needed.     

The seed ecology of an ornamental wattle in South Africa — Why has Acacia elata not invaded a greater area?

Australian Acacia species introduced to South Africa as ornamentals have notably smaller invasive ranges than those introduced for forestry or dune stabilization. We asked whether the relatively small invasive extent of Acacia elata, a species used widely for ornamental purposes, is due to low rates of reproduction. Age at reproductive maturity, seed dispersal, annual seed production, seed bank dynamics and seed germination and viability were assessed at five sites in the Western Cape. Results indicate that A. elata has similar traits to other invasive Australia Acacia species: annual seed input into the leaf litter was high (up to 5000 seeds m^− 2); large seed banks develop (> 20,000 seeds m^− 2) in established stands; seed germinability is high (> 90%); seeds accumulate mostly in the top soil layers but can infiltrate to depths of 40 cm; and seed germination appears to be stimulated by fire. However the age at the onset of reproduction (~ 4 years) is longer than most widespread invaders (~ 3 years) and dispersal is fairly limited (seeds fell up to distances of 6 m from the parent canopy; the highest density of seed rain was found directly under the canopy with over 20% of seeds falling directly under the terminal branches). We suggest that the current limited distribution of invasive A. elata populations is the result of the relatively small size of initial populations (cf. large plantations and widespread plantings for forestry and dune stabilization species), the species' apparent lack of secondary dispersal vectors, and the planting of trees in gardens and urban settings offer limited opportunities for recruitment, proliferation and spread. The species is, however, increasing in abundance and range. We propose methods to improve management of invasions of the species. Management to reduce seed production of this species through classical biological control, as has been achieved for other Australian Acacia species in South Africa, should be prioritised.     

Pattern of ant diversity in Korea: An empirical test of Rapoport's altitudinal rule

Two diversity patterns (hump-shaped and monotonic decrease) frequently occur along altitude or latitude gradients. We examined whether patterns of ant species richness along altitudes in South Korea can be described by these patterns and whether ranges of ant species follow Rapoport's altitudinal rule. Ants on 12 high mountains (> 1100 m) throughout South Korea (from 33° N to 38° N) were surveyed using pitfall traps at intervals of 200–300 m altitude. The temperatures at the sampling sites were determined from digital climate maps. Ant species richness decreased monotonically along the altitudinal gradient and increased along the temperature gradient. However, species richness of cold-adapted species (highland species) showed a hump-shaped pattern along altitude and temperature gradients. The altitude and temperature ranges of ant species followed Rapoport's rule. Sampling site temperature ranges were significantly correlated with coldness. Therefore, Rapoport's rule can be explained by high cold-tolerance of species inhabiting high altitudes or latitudes.     

Tradescantia fluminensis,an exotic weed affecting native forest regeneration in New Zealand: Ecological surveys,safety tests and releases of four biocontrol agents from Brazil

In the native range of Tradescantia fluminensis in SE Brazil surveys revealed a natural enemy biota attacking the plant that was rich in potential biocontrol agents for New Zealand (NZ), including nine fungi and 10 herbivorous insect species. Similar surveys in NZ, where T. fluminensis is an invasive exotic weed, revealed no specialist insect herbivores or pathogens. The Brazilian insect herbivores included leafmining, stemboring and gall-forming feeding guilds that were absent in NZ. Mean foliar damage levels per site on T. fluminensis were 7.8× higher for folivores in Brazil cf. NZ, and 21.2× higher for pathogens. The presence of rust pustules, or ‘brown lesions’, on leaves in Brazil was negatively associated with damage by folivores, perhaps indicating an antagonistic interaction. In contrast, damage by the white smut fungus, Kordyana sp., was not negatively associated with folivore damage. Mean dry biomass of T. fluminensis was significantly lower in Brazil (164 g m^?2) cf. NZ (455 g m^?2). In NZ, 85% of sites had biomass measures >200 g m^?2 (the previously determined threshold above which native forest regeneration fails). In Brazil, only 27% of sites had biomass measures >200 g m^?2. Among the insect herbivores, three chrysomelid beetles, Neolema ogloblini, Neolema abbreviata and Lema basicostata were prioritised as potential biocontrol agents. Their larvae cause potentially complementary damage to leaves, shoot-tips and mature stems, respectively. Several pathogens, including a rust, were rejected before we selected the Kordyana species. Host range testing of all four agents showed sufficient host-specificity for consideration for release in NZ. Neolema ogloblini and L. basicostata were field-released in NZ in 2011 and 2012, with the field-release of N. abbreviata due late 2012. An application to release Kordyana sp. in NZ has been made.     

Status,future prospects,and management recommendations for alkaline fens in an agricultural landscape: A comprehensive survey

Due to agricultural intensification and cessation of traditional land use, alkaline fens of the Caricion davallianae alliance (EU-FFH 7230) are among the most endangered ecosystems in Europe. This study exhibits a vegetation analysis of these systems in Schleswig-Holstein (Northern Germany). We analyzed across three scales the effects of grazing and mowing on phytodiversity of core areas and recorded their adjacent vegetation to estimate the capability for habitat enlargement of fen species. Results revealed that species richness, evenness and number of endangered species varied insignificantly between mowing and grazing treatments, regardless of scale. The high proportion of fen species and Red-Book-listed species in core areas, along with a state-wide representation of only 2 ha of these vegetation types, underlines the need for further conservation measures. Floristic differences between grazed and mowed sites derived from the individual appearance of species within one treatment. Thus, to preserve the species pool of alkaline fens, both management strategies have to be considered. Moreover, as most small sedge reed species are low-productive and light-demanding, sufficient biomass removal of dominant tall-growing species is required. One cut per year in late summer, the traditional management, does not satisfy the requirements of target species, which is indicated by an increase of Phragmitetea species at larger plot sizes. Additionally, in grazed fens, vegetation adjacent to the core areas consisted mainly of more eutrophic wet grasslands, and, in mowed fens, mainly of reeds or woods. We recommend therefore several changes in current conservation measures that include an increase to two cuts per year in mowed fens, and stocking rates of at least 2 LU ha⁻¹ (summer grazing) or 0.7 LU ha⁻¹ (year-round grazing).     

Insecticide resistance monitoring and correlation analysis to select appropriate insecticides against Nilaparvata lugens (Stål), a migratory pest in Korea

Nilaparvata lugens Stål is one of the important migratory pests of rice paddy fields in Korea. Resistance levels to nine insecticides were monitored in 12 local strains and correlation analysis was conducted to determine cross-resistance relationships among the tested insecticides. The local strains revealed 1.3- to 28.0-, 1.6- to 6.0-, 2.8- to 237.0-, 0.6- to 0.9-, and 0.7- to 1.3-fold resistance to carbamates, organophosphates, neonicotinoids, fipronil and etofenprox, respectively. Organophosphate insecticides revealed moderate correlations with benzofuranyl methylcarbamate (r = 0.566–0.614, p > 0.01). Three neonicotinoids were not correlated with each other, but imidacloprid and clothianidin were moderately correlated with several benzofuranyl methylcarbamate and organophosphate insecticides (r = 0.590–0.705, p > 0.05), indicating that unknown common factors (such as detoxification enzymes) might contribute to resistance to both insecticides. Fipronil and etofenprox exhibited low levels of resistance and cross-resistance with other insecticides, suggesting their potential as an effective insecticide for field application. Resistance level monitoring and correlation analysis would be valuable for the selection of appropriate insecticides to control insecticide-resistant N. lugens, a typical migratory pest in Korea.     

The role of winter weather in the population dynamics of spring moths in the southwest Korean peninsula

Moth monitoring in a coniferous forest in southwestern Korea was carried out for 3 years in order to investigate the effects of winter weather factors on moth survival and emergence in early spring. A total of 686 individuals in 51 species of 4 families were collected during 3 spring sampling periods. The species richness observed for all 3 years was similar, though their abundance was differed. A total of 15 weather variables were analyzed including temperature and precipitation during the 4 months preceding April, and cumulative sums of 5-degree days with base temperatures ranging from 6 to 10 °C. Due to the multicollinearity of dependent variables, we adopted the eigenvectors of major axes from principal component analysis for multiple stepwise regression analysis. The species richness and abundance were significantly related to the first and second axes. Both axes were positively related with precipitation and temperature during the preceding 2 months, as well as the average winter temperature. This indicated that the effects of temperature and precipitation during winter played an important role in moth emergence in early spring, though the weather conditions of each month during winter varied significantly compared to the pattern of adult emergence.     

Impact of minimum winter temperature on Lycorma delicatula (Hemiptera: Fulgoridae) egg mortality

Climate change, especially winter temperature increase, may be a factor the recent occurrence and range expansion of Lycorma delicatula (White) in South Korea. Egg mortality increased as minimum winter temperature decreased. Egg mortality was highest (93.32%) in Chuncheon, where the mean minimum winter temperature was lowest. The temperature that induced complete mortality of fulgorid eggs was estimated to be ?3.44 °C on the basis of mean daily temperatures from December 2009 to February 2010 and ?12.72 °C on the basis of mean daily minimum temperatures in January 2010. Mean winter temperatures during the last 30 years have gradually increased to above the temperature for 100% mortality of the fulgorid egg. This suggests that the winter temperature increase may contribute to the successful settlement of the fulgorid in South Korea and its subsequent outbreak and expansion.     

High risk of the fall armyworm invading Japan and the Korean Peninsula via overseas migration

The fall armyworm, Spodoptera frugiperda (J.E. Smith), is an invasive pest species in the Old World. This species is originally native to the Americas. Since 2016, S. frugiperda has spread widely and rapidly throughout Africa, the Middle East, India, Southeast Asia and, most recently, to southern China. By May 2019, S. frugiperda had appeared in 13 provinces in southern China and will spread further into northern China. It is highly likely that S. frugiperda will enter Japan and Korea via overseas migrations as have many other migratory pests. To evaluate the risk of S. frugiperda invasion in Japan and the Korean Peninsula, we modelled the rate of expansion and future potential migratory range of the insect by a trajectory analytical approach using the flight behaviour of S. frugiperda and meteorological data of the past five years (2014–2018). If S. frugiperda can fly for up to 36 continuous hours over water, then our results predict migration from southern and eastern China into Japan and Korea. Most likely, Japan would be invaded from Fujian and Zhejiang in 1 June–15 July, and Kyushu, Shikoku and southwestern Honshu could face the highest risk of S. frugiperda invasion. Korea would most likely be reached by S. frugiperda from northern Zhejiang, Jiangsu, Anhui and Shandong in 1 June–15 July and later. Our results indicated a very high risk that S. frugiperda would annually invade Japan and the Korean Peninsula and cause a possible significant decrease in agricultural productivity.     

Survey of phytophagous insects and foliar pathogens in China for a biocontrol perspective on kudzu,Pueraria montana var. lobata (Willd.) Maesen and S. Almeida (Fabaceae)

A three-year survey of kudzu foliage, seed, stems, and roots for associated phytophagous insects was conducted to establish basic information about the insect communities that kudzu harbors in China and to assess the abundance, diversity and damage caused by these insects. Diseases of kudzu were also surveyed in southern China. A total of 116 phytophagous insect species in 31 families and 5 orders were collected from kudzu in China, in six feeding guilds: foliage, sap, stem, terminal, seed and root feeders. The impact of foliage feeders varied from site to site and year to year, and over the course of the growing season. The mean percent defoliation of kudzu over all plots and years was 13.3 ± 1.9%, but ranged as high as 34%. Two insect species fed on shoots and clipped off terminals. Infestation of new shoots was high, with nearly half of all shoots clipped. Nearly half of the vines showed damage from stem borers, again varying through the season. Two species of insects attacked kudzu roots, mainly the cerambycid beetle Paraleprodera diophthalma (Pascoe), which caused considerable damage to both small (young, <3.4 cm diameter) and large (older, >6 cm diameter) roots. Insects also caused substantial seed damage. Imitation rust, caused by Synchytrium minutum [=S. puerariae (P. Henning) Miyabe], was the most commonly observed disease of kudzu. Several of these species have potential as biological control agents for kudzu in the US.