Earthworm Diversity Research Articles

DNA barcoding: How many earthworm species are there in the south of West Siberia?

Earthworms are a widespread and ecologically important group of animals, which has the highest total biomass in some ecosystems and often defines the composition of soil fauna. Earthworms are known to have high cryptic genetic diversity. In this study we attempted to estimate earthworm species diversity in the south of West Siberia by DNA barcoding. This method employs short fragments of the genome to identify species, and allows one to work with specimens that cannot be identified by conventional techniques, as well as to search for new species and predict their phylogenetic affinities. As the target sequence we took a fragment of the mitochondrial cytochrome oxidase 1 (cox1) gene. The studied territory (Novosibirsk and Tomsk oblasts, Altai krai, and the Altai Republic) is known to contain 16 species and subspecies of earthworms. We analyzed 259 individuals from twelve locations and detected 27 genetic clusters. Ten of them correspond to known species (A. caliginosa, E. fetida, O. tyrtaeum, D. rubidus tenuis, D. octaedra, E. balatonica, E. sibirica, as well as three genetic lineages ofE. nordenskioldi nordenskioldi). Seventeen of the 27 clusters do not have close sequence similarity to any known earthworm species. Representatives of some of these novel clusters are morphologically similar to the Eisenia n. nordenskioldi/E. n. pallida species complex and may belong to new genetic lineages of this complex. The rest of the novel clusters probably represent new earthworm species. Therefore, we can conclude that a large portion of earthworm biodiversity in the south of West Siberia is still unexplored.

The population of earthworms (Lumbricidae) in the main types of dark coniferous forests in Pechora-Ilych Nature Reserve

The population of earthworms has been studied in the main types of old-growth dark coniferous forests of Pechora-Ilych Nature Reserve (Komi Republic) that have not been subject to anthropogeniс impact for a long time. Ten species of earthworms have been identified. The greatest diversity (7 species), abundance, and biomass of earthworms has been revealed in the tall-grass fir–spruce forests. P. diplotetratheca had the greatest abundance. E. nordenskioldi nordenskioldi and E. atlavinyteae had the greatest biomass. The lowest species diversity (3 species), abundance, and biomass of earthworms have been found in the largefern, blueberry–green moss, and sphagnum–horsetail fir–spruce forests. The role of deadwood in maintaining the species diversity of Lumbricidae in dark coniferous forests has been demonstrated. The complexes of Lumbricidae have been considered in anthropogenically disturbed territories, where the following species with a habitat range to the south of the northern and middle taiga have been identified: L. rubellus, A. rosea, A. caliginosa caliginosa, and E. fetida.

우리나라 골프장의 지렁이 종 다양성 및 계절별 군집 구조

Earworm is very useful animal in soil ecosystem, however it is harmful for golf courses because they introduce many cast on turfgrass that reduces turf uniformity and play quality. However, no information has found on earthworm diversity and seasonal fluctuation in different Korean golf courses. In this study, we focused to carry out earthworm species composition and seasonal population structure in turfgrass of golf courses. During spring and fall season survey with direct digging and tea saponin drenching sampling in 5 different golf courses, 6 species under 3 families of earthworms were collected. Earthworm species composition and density was different among the golf courses. Aporrectodea caliginosa in Lumbricidae was dominant species in Anseong and Dongrae Benest Golf Club; however Amynthas carnosus in Megascolecidae was dominant species in Anyang and Glenrose Golf Club. Ap. caliginosa was collected only aclitellum in July and Am. carnosus was collected aclitellum and clitellum in August in golf courses. Seasonal population of earthworm was different depending on earthworm species (Am. hupeiensis was the highest in August and Ap. caliginosa was in April) however small number of collected earthworm species were not dominant trend in golf courses.

Do the rich get richer? Varying effects of tree species identity and diversity on the richness of understory taxa.

Understory herbs and soil invertebrates play key roles in soil formation and nutrient cycling in forests. Studies suggest that diversity in the canopy and in the understory are positively associated, but these studies often confound the effects of tree species diversity with those of tree species identity and abiotic conditions. We combined extensive field sampling with structural equation modeling to evaluate the simultaneous effects of tree diversity on the species diversity of understory herbs, beetles, and earthworms. The diversity of earthworms and saproxylic beetles was directly and positively associated with tree diversity, presumably because species of both these taxa specialize on certain species of trees. Tree identity also strongly affected diversity in the understory, especially for herbs, likely as a result of interspecific differences in canopy light transmittance or litter decomposition rates. Our results suggest that changes in forest management will disproportionately affect certain understory taxa. For instance, changes in canopy diversity will affect the diversity of earthworms and saproxylic beetles more than changes in tree species composition, whereas the converse would be expected for understory herbs and detritivorous beetles. We conclude that the effects of tree diversity on understory taxa can vary from positive to negative and may affect biogeochemical cycling in temperate forests. Thus, maintaining high diversity in temperate forests can promote the diversity of multiple taxa in the understory.

DNA barcoding: how many earthworm species are there in the south of West Siberia?

Earthworms are a widespread and ecologically important group of animals, which has the highest total biomass in some ecosystems and often defines the composition of soil fauna. Earthworms are known to have high cryptic genetic diversity. In this study we attempted to estimate earthworm species diversity in the south of West Siberia by DNA barcoding. This method employs short fragments of the genome to identify species, and allows one to work with specimens that cannot be identified by conventional techniques, as well as to search for new species and predict their phylogenetic affinities. As the target sequence we took a fragment of the mitochondrial cytochrome oxidase 1 (cox1) gene. The studied territory (Novosibirsk and Tomsk oblasts, Altai krai, and the Altai Republic) is known to contain 16 species and subspecies of earthworms. We analyzed 259 individuals from twelve locations and detected 27 genetic clusters. Ten of them correspond to known species (A. caliginosa, E. fetida, O. tyrtaeum, D. r. tenuis, D. octaedra, E. balatonica, E. sibirica, as well as three genetic lineages of E. nordenskioldi nordenskioldi). Seventeen of the 27 clusters do not have close sequence similarity to any known earthworm species. Representatives of some of these novel clusters are morphologically similar to the Eisenia n. nordenskioldi/E. n. pallida species complex and may belong to new genetic lineages of this complex. The rest of the novel clusters probably represent new earthworm species. Therefore, we can conclude that a large portion of earthworm biodiversity in the south of West Siberia is still unexplored.

A molecular phylogenetic study of pheretimoid species (Megascolecidae) in Mindanao and associated islands, Philippines

The knowledge on earthworm taxonomic studies in the Philippines over the past decade dramatically increased and the results indicate an astonishingly high diversity and high local endemicity of earthworms in the country. The earthworm fauna of the Philippines is composed of pheretimoid species of the family Megascolecidae. A molecular phylogenetic study was done in attempt to infer phylogenetic relationships among the pheretimoid species in Mindanao and associated islands. Gene markers used include the mitochondrial cytochrome c oxidase subunit I (COI) and 16S rRNA, and the nuclear 28S rRNA and protein-coding histone H3 genes. Despite having limited taxa and limited genes included in the analyses, the combined data set generated a phylogeny more or less consistent with morphology-based expectation. Sims and Easton's classification scheme published in 1972 does not reflect the phylogeny with respect to the genus Amynthas and the subgenus Parapheretima; the characters they used to define these taxa are homoplasious. The species groupings in Pheretima based on the location of spermathecae are partially reflected the pheretimoid phylogeny. Particularly, members of the Pheretima sangirensis group formed a clade supported with 0.99 posterior probability with the inclusion of P. (Parapheretima) pandanensis (also with spermathecal pores at 7/8), the monothecate Pheretima vergrandis with spermathecal pore at 7/8, and an athecate conspecific of Pheretima apoensis. The members of the Pheretima urceolata group also form a weakly supported clade with the inclusion of the monothecate P. (Parapheretima) boaensis (with spermathecal pores at 5/6) and the athecate Amynthas dinagatensis. Moreover, loss of spermatheca or fusion of two spermathecae into one can occur in pheretimoid evolution, such as in the case of the monothecate P. vergrandis and the athecate conspecific of P. apoensis. Several of the branch nodes of the tree based on combined data set have support values that are very weak and formed polytomies, which is most likely due to insufficient data. The results could have improved if more data were available. The addition of genes with divergence rates slower than that of COI and 16S but faster than that of 28S and H3, such as 12S and ITS2, may also improve the resolution. Further molecular work including more taxa is needed to be able to establish a more robust system of classification of the pheretimoid species and come up with a better-resolved phylogeny. A consolidated phylogenetic study in the East Asian archipelagos will provide insights into the evolutionary, biogeographic, and ecological processes involved in island radiations of soil-dwelling animals.

Earthworm Communities in the Bamboo Plantations of West Tripura (India)

Present study revealed the presence of 16 earthworm species belonging to 11 genera and four families viz. Megascolecidae (Amynthus alexandri, Metaphire houlleti, Lampito mauritii, Kanchuria sp1, Perionyx excavatus), Octochaetidae (Eutyphoeus gigas, Eutyphoeus comillahnus, Eutyphoeus orientalis, Octochaetona beatrix, Dichogaster bolaui, Lennogaster chittagongensis, Lennogaster yeicus), Moniligastridae (Drawida papillifer papillifer, Drawida assamensis, Drawida nepalensis) and Glossoscolecidae (Pontoscolex corethrurus) in the soils of five bamboo species [Bambusa balcooa (Sil Barak), Melocanna baccifera (Muli), Bambusa polumorpha (Bari), Bambus cacharensis (Bom) and Bambus bambus (Katabarak)] of West-Tripura. While four earthworm species viz. Metaphire houlleti, Drawida assamensis, Drawida papillifer papillifer and Pontoscolex corethrurus were common to all species of bamboo plantations, the rest showed restricted distribution. Among the earthworm species 4 were exotic (Amynthus alexandri, Metaphire houlleti, Dichogaster bolaui and Pontoscolex corethrurus) and the others were native to the Indian sub-continent. In general, earthworms under the bamboo plantations occurred within temperature range of 21.6 °C–28.0 °C, pH 4.0–7.0, organic matter 0.56–5.99 %, moisture 9.6–31.7 %, water holding capacity 14.6–43.9 % and bulk density 0.7–1.8 g cm−3. The average density and biomass of the earthworms in the studied places were 108 ind m−2 and 44 g m−2 respectively. Earthworm diversity, dominance and evenness indices showed the values 1.00, 0.47 and 0.70 respectively. Earthworm density and biomass showed a negative correlation with temperature whereas those had a strong positive correlation with pH, moisture and organic matter of the soils.

Earthworm distribution and density across a climatic gradient within the Inland Pacific Northwest cereal production region

Despite their recognized importance in promoting crop yields and soil health, little is known about earthworm species composition and density within the cereal production region of the Inland Pacific Northwest (IPNW). The overall goal of this work was to understand the influence of climatic factors and soil properties on the presence/absence and density of earthworm species found in the region. The IPNW cereal production region includes a steep climatic gradient and can be divided into four agroecological classes (annual cropping, transition crop-fallow, crop-fallow and irrigated) (AECs) according to the dominant cropping systems present. Replicate sites were selected within the annual cropping, transition and crop-fallow AECs and earthworm density, diversity and soil properties were measured. Earthworm diversity was extremely low. Only two of the sampled sites had more than a single species, and these sites were both in the wettest AEC. Aporrectodea trapezoides was the predominant species sampled, and this species was present at every site where earthworms were found. Earthworms were present at all sites within the annual cropping and transition classes, while only 13.3% of sites within the crop-fallow AEC had earthworms. When only sites with earthworms were considered, earthworm metrics were greater in the driest crop-fallow AEC (density=151.2 individuals m−2) compared to 113.8 individuals m−2 in the transition and 86.4 individuals m−2 in annual cropping fields and a significant negative correlation was found with precipitation. The data suggest that while earthworms are largely absent from the driest sites, they can achieve relatively high density and biomass values when local conditions (soil properties and management) are favorable. A clear minimum threshold of mean annual precipitation (MAP) between 330 and 370mm was observed, with earthworms absent from all fields with MAP values below 330. This value is lower than those previous reported for A. trapezoides and demonstrates the species’ ability to deal with warm, dry conditions. Biomass values (mean of 94.3gm−2) for sites with earthworms were generally above those reported to be necessary to significantly influence crop yields, suggesting that further research focusing on quantification of the impact of earthworm on crop yields in this important agricultural region is warranted.

Diversity of earthworms (Clitellata: Lumbricidae) from Sredna Gora Mountain (Bulgaria)

In the current study the diversity, zoogeographical position and distribution of earthworms from Sredna Gora Mountain (Bulgaria) is presented. During the present investigation, altogether ten earthworm species belonging to seven genera were collected. Among them, seven taxa are reported for the first time from the Sredna Gora Mt.: Cernosvitovia rebeli, Dendrobaena alpina, Allolobophoridella eiseni, Dendrodrilus rubidus rubidus, Aporrectodea caliginosa, Aporrectodea rosea and Lumbricus terrestris. On the basis of the new and literature data here we provide the first list of lumbricid earthworms from Sredna Gora Mountain.

Earthworms stimulate pasture production in sheep and beef systems: their economic value

Earthworms have long been recognised to promote plant growth but their contribution to pasture production in managed pastures may be undervalued. At three field sites pasture production was measured in an area where surface active communities were found compared to a more diverse area where the additional deep burrowing earthworm Aporrectodea longa had been introduced. Caution is needed when interpreting the results, as all data are from paired areas and not replicates. The influence of earthworms on pasture production was positively correlated with the difference in abundance of the topsoil species Aporrectodea caliginosa, with this species being more abundant in the presence of A. longa at two sites. Overall, the value of diverse earthworm communities to pasture production was estimated to be $365-$440/ha annually. In managed pasture systems there is need to recognise the value of maintaining and enhancing earthworm populations. Keywords: pasture production, earthworm functional diversity

Earthworm diversity and ecosystem services in agriculture: Choosing appropriate taxon indicators and measurements

Agriculture and biodiversity are strongly linked. Whilst agriculture is a main driver impacting biodiversity, farmers could benefit from ecosystem services linked to biodiversity. Hence, indicators of functional biodiversity are needed. However, finding correct indicator values is not trivial. Earthworms were sampled on nine German farms with a combined method. In total 3205 earthworms from 10 species were collected. Six measurements applicable as taxon indicators were calculated for the data. Keywords: soil diversity, interpolation, extrapolation, biodiversity indices, biodiversity estimators

Landscape Patch Pattern Effect on Relationships between Soil Properties and Earthworm Assemblages: A Comparison of two Farmlands of Different Spatial Structure

ABSTRACT Our survey was carried out in two study sites of approximately 3.3 ha each located in the Suwalki Lake District in NE Poland in the year 2008. Earthworms and soil samples were collected during two campaigns (spring and autumn) from 25 × 25 cm and 30 cm deep sampling points. The complex arable landscape (CAL) supported higher earthworm diversity, density and biomass than the similarly managed but homogeneous arable landscape (HAL). The spring and autumn earthworm sampling campaigns revealed very different patterns, and we conclude that autumn sampling is the most adequate for biomonitoring. On the other hand, the spring collections were significantly correlated to soil physical parameters, thus spring sampling is more suitable for studying such correlations. Significant correlations occurred almost exclusively for CAL and the soil parameters significantly relating with earthworm community were: soil moisture, nitrogen and organic carbon contents. The possible reason for it is the presence of numer...

Earthworm functional traits and interspecific interactions affect plant nitrogen acquisition and primary production

We performed a greenhouse experiment to test how the functional diversity of earthworms, the dominant group of soil macro-invertebrates in many terrestrial ecosystems, affects nitrogen cycling and plant growth. Three species were chosen to represent a range of functional traits: Lumbricus terrestris (large, mainly detritivorous, makes vertical permanent burrows open at the surface), Aporrectodea longa (medium-large, feeds on both detritus and soil, makes burrows more branched than L. terrestris), and Allolobophora chlorotica (small, geophagous, makes ephemeral burrows below the soil surface). Mesocosms with ryegrass (Lolium perenne) were inoculated with none to all three species (similar total biomass), using an experimental design (Simplex) suited to partition single species and diversity effects. Two contrasting N sources, urea or mammalian dung, were labelled with 15N so that the acquisition by plants and earthworms and recovery of applied 15N could be estimated.Over 3 months, plant production was higher with urea applications, but there were also species-specific earthworm effects: A. chlorotica and, to a lesser extent, A. longa increased shoot biomass, whereas L. terrestris increased root biomass. Earthworms did not affect soil N concentrations or leaching losses, whereas more N was leached under urea. A. chlorotica tended to increase dung-15N recovery in grass shoots, but in interaction with A. longa had the opposite effect, possibly through increased N immobilization in the microbial biomass. Earthworms assimilated negligible amounts of urea-15N but a substantial proportion (17% on average) of the dung-15N, with no clear-cut differences between species. Our findings show that earthworm species may have similar trophic response to N sources and yet different effects on plant N uptake and primary production, and that inter-specific earthworm interactions can result in non-additive diversity effects.

Dynamics of earthworm taxonomic and functional diversity in ploughed and no-tilled cropping systems

No-till has been proposed to limit the negative impacts of intensive agriculture. Soil organisms such as earthworms are good indicators of soil tillage effects. The aim of this study was to assess the dynamics of both taxonomic and functional diversity of earthworm communities after switching from ploughing i.e. deep tillage at 25–30cm depth inducing soil inversion in this paper, to no-till. We assumed (i) that this transition led to increased diversity and (ii) that both taxonomic and functional indices indicated changes in tillage practices. Earthworms were sampled at three experimental sites in France on a Cambisol, a Luvisol, and a Fluvisol over several years (from 1995 to 2011), comparing both tillage systems. Standardized mean differences (Cohen’s indices) were calculated on several taxonomic and functional indices to quantify the influence of tillage practices within each site. We generally found a neutral or positive effect of the no-till on taxonomic and functional indices. The temporal responses of earthworm diversity were stronger in earliest stages (less than 6 years) than in oldest ones (more than 8 years) revealing transitory effects on diversity. In site III, for instance, a positive effect of no-till was observed on species and functional richness during the first 5 years but a negative effect was shown in year 6. Thus, no clear continuous increase of taxonomic and functional diversity was found in no-tilled fields, but positive and negative effects according to sites and years. More marked differences were found for taxonomic than for functional indices, suggesting that individuals settling the fields shared a similar combination of functional traits to those previously present. As transitory effects have been observed, this study highlighted that long-term trials are needed to assess the effects of cropping systems on earthworm biodiversity.

Agricultural management and flooding shape habitats for non-native earthworms in southern Quebec, Canada

Agricultural intensification leading to the cultivation of unmanaged field margins along rivers and streams is expected to impact soil biodiversity. Earthworm communities are typically smaller with fewer species in agricultural soils, but the effect of agriculture on earthworms could be mitigated by the more favorable soil moisture regime in riparian areas, as well as planting perennial grasses or keeping forest fragments as permanently vegetated buffers. The objective of this study was to compare earthworm community composition under contrasting land use (agricultural vs. riparian forest) ∼5m and ∼30m away from the Pike River in southern Quebec, Canada. Furthermore, we evaluated how earthworm communities were affected by management intensity, flooding, soil and vegetation patterns within these land uses. We established 4 transects at 3 sites along the Pike River representing 4 land uses (agricultural field, agricultural buffer, riparian forest fragment, upland forest fragment). Along each transect, earthworm populations and soil properties were evaluated at 5 discrete points on 4 occasions from fall 2009 to spring 2011. Vegetation cover and plant species richness were measured, and management and flooding intensity were documented through farmer surveys. Earthworm abundance and diversity were highest in a riparian forest transect (460individualsm−2, 9 species) and agricultural buffer (325individualsm−2, 10 species), and lowest in the agricultural fields with annual crop rotations and agrochemical inputs, which also had the lowest plant diversity. Redundancy analysis revealed that differences in earthworm species compositions across the study area were linked to site-specific management and flooding, represented by differences in soil moisture, vegetation diversity, and soil nutrient concentrations (dissolved organic carbon in soil solution, mineral nitrogen, extractable phosphorus). Generalized linear mixed modeling also showed that less intensively managed agricultural buffers and forest fragments with regular flooding supported higher earthworm diversity. We recommend further research on soil functions affected by earthworms in riparian areas because these non-native earthworms could affect the conservation value of unmanaged agricultural buffers and forest fragments in southern Quebec, Canada.

Environmental costs and benefits of growing Miscanthus for bioenergy in the UK.

Planting the perennial biomass crop Miscanthus in the UK could offset 2–13 Mt oil eq. yr−1, contributing up to 10% of current energy use. Policymakers need assurance that upscaling Miscanthus production can be performed sustainably without negatively impacting essential food production or the wider environment. This study reviews a large body of Miscanthus relevant literature into concise summary statements. Perennial Miscanthus has energy output/input ratios 10 times higher (47.3 ± 2.2) than annual crops used for energy (4.7 ± 0.2 to 5.5 ± 0.2), and the total carbon cost of energy production (1.12 g CO2‐C eq. MJ−1) is 20–30 times lower than fossil fuels. Planting on former arable land generally increases soil organic carbon (SOC) with Miscanthus sequestering 0.7–2.2 Mg C4‐C ha−1 yr−1. Cultivation on grassland can cause a disturbance loss of SOC which is likely to be recovered during the lifetime of the crop and is potentially mitigated by fossil fuel offset. N2O emissions can be five times lower under unfertilized Miscanthus than annual crops and up to 100 times lower than intensive pasture. Nitrogen fertilizer is generally unnecessary except in low fertility soils. Herbicide is essential during the establishment years after which natural weed suppression by shading is sufficient. Pesticides are unnecessary. Water‐use efficiency is high (e.g. 5.5–9.2 g aerial DM (kg H2O)−1, but high biomass productivity means increased water demand compared to cereal crops. The perennial nature and belowground biomass improves soil structure, increases water‐holding capacity (up by 100–150 mm), and reduces run‐off and erosion. Overwinter ripening increases landscape structural resources for wildlife. Reduced management intensity promotes earthworm diversity and abundance although poor litter palatability may reduce individual biomass. Chemical leaching into field boundaries is lower than comparable agriculture, improving soil and water habitat quality.

EARTHWORM DIVERSITY AND ECOSYSTEM SERVICES UNDER THREAT

Biodiversity affects human well-being and represents an essential determinant of ecosystem stability. However, the importance of below-ground biodiversity, and earthworm biodiversity in particular, has not received much attention. Earthworms represent the most important group of soil macrofauna. They play a crucial role in various biological processes in soil, and affect ecosystem services such as soil health and productivity, water regulation, restoration of degraded lands, and the balance of greenhouse gases. Anthropogenic activities can lead to a rapid reduction or loss of earthworm diversity, and threaten ecosystem services as well as human well-being. Therefore, conservation of earthworm diversity should receive urgent attention. Farmers need to be made aware of the importance of earthworm diversity conservation and its benefits. Local ecological knowledge is required for communication between scientists and farmers; moreover, efficient strategies for earthworm diversity conservation need to be developed. This paper intends to communicate the importance of earthworm diversity conservation. Development of conservation management to prevent earthworm diversity decline should be done wisely and involve all stakeholders.

DNA-barcoding of invasive European earthworms (Clitellata: Lumbricidae) in south-western Australia

Using DNA-barcoding, we studied the diversity of invasive European earthworms in the south-western corner of Australia. We found six Molecular Operational Taxonomic Units belonging to five morphospecies: Aporrectodea caliginosa, A. trapezoides, Dendrobaena cf. attemsi, Eiseniella tetraedra and Octolasion cyaneum. These were variously collected from indigenous forests and/or alienated land. Two cryptic lineages were found within A. trapezoides, and high intraspecific genetic variation was also found within E. tetraedra-variation that had previously been documented in Europe. Our study demonstrates the usefulness of DNA-barcoding for the identification of earthworms, including cryptic species. Correct identification and high taxonomic resolution is crucial for the monitoring of cryptic diversity, detecting new introductions and monitoring spread of established exotic earthworms.

Landscape-scale distribution patterns of earthworms inferred from soil DNA

Assessing land-use effect on the diversity of soil biota has long been hampered by difficulties in collecting and identifying soil organisms over large areas. Recently, environmental DNA-based approaches coupled with next-generation sequencing were developed to study soil biodiversity. Here, we optimized a protocol based on soil DNA to examine the effects of land-use on earthworm communities in a mountain landscape. This approach allowed an efficient detection of earthworm diversity and highlighted a significant land-use effect on the distribution patterns of earthworms that was not revealed by a classical survey. Our results show that the soil DNA-based earthworm survey at the landscape-scale improves over previous approaches, and opens a way towards large-scale assessment of soil biodiversity and its drivers.

Earthworm Communities in Previously Glaciated and Unglaciated Eastern Deciduous Forests

Native earthworms were removed from forested ecosystems during the last glacial advance and have since been replaced with nonnative earthworm species. Nonnative earthworms can cause major changes in microbial and plant communities and nutrient cycling. In this study, we sought to compare the earthworm communities north and south of the last glacial terminus, and to examine correlations between plant communities and soil characteristics. In summer 2011, we measured the earthworm, herbaceous plant, and woody plant communities in 3 forests in southwestern Ohio and 3 forests in northern Kentucky. We also measured soil characteristics including moisture, pH, organic matter, and nitrate and ammonium content. We found no native earthworm species at any of our study sites; however, previously glaciated forests exhibited more diverse earthworm communities and included all ecological groups. Earthworm species richness increased with increased density of invasive woody plant species and decreased with increased soil ammonium. Scientists and managers should continue to survey the earthworm communities in forests to better understand the ranges of nonnative earthworms and the impacts they have on plant communities and nutrient dynamics.