Elaiosome Removal Research Articles

Ant handling changes myrmecochore seed coat microbiomes and alters diversity of seed‐borne plant pathogenic fungi

Abstract The putative benefits to seeds in myrmecochory (ant‐mediated seed dispersal) are often cast in a reward context. However, microbes have been mostly overlooked as seed mortality agents in myrmecochory, as have potential treatments provided by ant‐handling. We investigated the effects of ant handling on the diversity of seed coat fungal communities of three myrmecochorous plant species. Ant‐handling altered measures of both alpha and beta diversity of fungal communities. Ant‐handled seeds harboured different overall fungal communities and plant pathogen communities than non‐ant‐handled seeds. The myrmecochore pathogenic fungal community showed high dissimilarity (high pairwise community turnover) between ant‐handled and control seeds, while beta diversity measures for ant‐handled seeds and seeds with manually removed elaiosomes were less dissimilar. Ant handling may offer an additional benefit to myrmecochorous seeds via the reduction in the seed coat pathogenic community, which may be driven by elaiosome removal or as a by‐product of ant cleaning behaviours and chemical secretions. Read the free Plain Language Summary for this article on the Journal blog.

What are elaiosomes for? Effects of elaiosomes on ant attraction, seed removal and germination in wild chaya (Cnidoscolusaconitifolius)

Seed dispersal by ants is common in arid lands. The seeds of myrmecochorous plants bears an elaiosome, an appendage that acts as a reward for ants. Once an ant identifies an elaiosome-bearing seed, it carries the diaspore to the nest, removes the elaiosome and discards the seed. During elaiosome removal, ants also scarify the seed, which may favor seed germination or facilitate pathogen attack. Some elaiosomes are hygroscopic and therefore, this could increase water intake and retention. We assessed the effect of elaiosome removal, seed scarification and fungal infection on germination in Cnidoscolus aconitifolius, a plant species common in the arid tropics of the Americas. The effects of elaiosome removal on ant attraction and seed removal were also assessed. According to the results, the elaiosome of C. aconitifolius increases the attractiveness of its seeds to ants, but did not affect seed removal or seed germination. Also, the elaiosome significantly increased the chance of pathogen attack on the seed. The benefits of elaiosome removal on seed germination were mediated by physical scarification, with greater germination in scarified seeds without elaiosomes. Seed scarification did not affect the likelihood of fungal attack.

Seed dispersal mechanism of Erythronium japonicum in Northeast China

Seed dispersal is recognized as a very important stage in the life history of plant sexual reproduction. Seed dispersal directly determines whether plant seeds can reach the favorable germination sites and ensure the successful germination of seeds subsequently which is the first stage of plant seedling establishment. The final dispersal location of seeds with diplochory usually requires the joint decision of two stages including primary seed dispersal and secondary seed dispersal. The seed dispersal of Erythronium japonicum by ants was investigated in three different habitats. The effect of seed maturity on seed fate and the effects of elaiosome removal and water immersion on seed dispersal in the wild were studied. The results showed that eight species of ants were involved in E. japonicum seed dispersal in the three habitats. The seed handling efficiency and the number of seeds transported by ants were affected by the composition of ant community and the size of ant population. There was a strong correlation between the seed dispersal distance and the body length of ants. Small ants may have expanded their foraging range through fierce struggle. The immature E. japonicum seeds will also be handling by ants, indicating that the seed elaiosome mature prior to seeds. We found elaiosome plays an important role in the dispersal of E. japonicum seeds, and it can also be used as a “handle point” for smaller ants. The components of elaiosome are not easily soluble in water, which can avoid the loss of the attraction of E. japonicum seeds to ants due to the rain during the seed dispersal process.

Seed Elaiosome Mediates Dispersal by Ants and Impacts Germination in Ricinus communis

Myrmecochory is ant-mediated secondary dispersal of seeds that depends on the presence of a lipid-rich seed appendage known as ‘elaiosome’. Attractive cues of elaiosome that drive such an interaction and benefits to the plant are not clearly understood. Here, using Ricinus communis, we establish reward compositions and determine the benefits of myrmecochory to the plant. We also compare elaiosome compositions across ecotypes. Our results show that the elaiosome is essential for seed displacement and olfactory cues are important attractive cues. Nonanal and 2-decenal were found to be the major attractive volatiles in the castor elaiosome. Different ant species showed different behavior towards elaiosome-bearing seeds. Among them, Pheidole grayi was efficient in dispersal but did not disperse all seed ecotypes tested. Major differences in fatty acid levels were observed between ecotypes. To determine the benefits of myrmecochory, germination rates before and after removal of elaiosome were studied. Seed germination improved upon elaiosome removal and aqueous elaiosome extract inhibited germination indicating water-soluble inhibitory factors. Further, ant nest sites were richer in nitrogen than control sites, revealing a clear benefit of seed displacement. In summary, we demonstrate the ecological significance of the seed elaiosomes in the absence of nutritive rewards for seed dispersers.

Seed Germination InViola pedunculataandViola purpureaSUBSP.Quercetorum(Violaceae), Critical Food Plants For Two Rare Butterflies

Viola L. are the larval food plants for a charismatic group of butterflies in Speyeria Scudder, 1872, which contains several rare and declining taxa in California and across North America. A current impediment to restoring Viola in California is a lack of knowledge of germination requirements. In this study we focused on determining conditions for successful germination of V. pedunculata Torr. & A. Gray, the food plant of the federally listed endangered Speyeria callippe (Boisduval, 1852) subsp. callippe, and V. purpurea Kellogg subsp. quercetorum (M.S. Baker & J.C. Clausen) R.J. Little, the food plant of the imperiled southern Coast Range butterfly, S. adiaste (Edwards, 1864) subsp. clemencei (Comstock, 1925). We examined the effects of gibberellic acid, seed color, elaiosome removal, and duration of stratification on germination success. We found that both taxa germinate exceptionally well (73–100%) after a prolonged period of after-ripening and 6–10 wk of stratification. Gibberellic acid and elaiosome removal did not have strong effects on germination of V. pedunculata, and both dark and mottled V. purpurea subsp. quercetorum seeds germinated equally well. We make recommendations for successful lab germination of these two native violets, setting the stage for additional research to help restore their populations as well as their herbivores.

Seed handling behaviours of native and invasive seed‐dispersing ants differentially influence seedling emergence in an introduced plant

Myrmecochory, or ant‐mediated seed dispersal, is an important ecological interaction in which ants benefit by gaining nutrition from lipid‐rich elaiosomes attached to seeds and plants benefit from having their seeds dispersed away from parent plants. Most research on the benefits of myrmecochory focuses on primary dispersal, in which ants move seeds to nests, or secondary dispersal, in which ants deposit intact seeds in middens after consuming elaiosomes. Less is known about how ants handle seeds inside nests and if handling influences plant fitness. The seed handling behaviours of a native ‘keystone disperser’, Aphaenogaster rudis s.l., and an invasive seed‐disperser, Myrmica rubra L., on an introduced herb, Chelidonium majus L., were compared. We conducted a greenhouse experiment to test if handling by ants, manual removal of elaiosomes, or no handling (controls) influenced seedling emergence. Colony‐level differences in handling behaviours and plant responses were also examined. Aphaenogaster rudis retained seeds inside nests longer than M. rubra, but there was no difference in the amount of elaiosome removed by the two species. There was no difference in the proportion of seedlings that emerged among treatments, but seedlings emerged earlier when handled by A. rudis. Additionally, more seedlings emerged and seedlings emerged earlier the longer seeds were retained inside ant nests. This study suggests that handling by ants may be a benefit of myrmecochory. This is probably not due to elaiosome removal; rather favourable nest conditions may enhance emergence. Also, functional differences in ant species may result in different outcomes for plant partners.

Seed germination of Viola pedata, a key larval host of a rare butterfly

Birdfoot violet ( Viola pedata L. [Violaceae]) is one of several Viola species that act as larval host plants for the rare regal fritillary butterfly ( Speyeria idalia Drury [Nymphalidae, Argynninae]). Restoration or expansion of existing populations of V. pedata populations can be an important tool for preventing local extinction of S. idalia . Knowledge of environmental cues that affect germination will contribute to restoration efforts. Our investigation of seed germination of V. pedata indicates stratification is necessary for germination. Seeds exposed to longer lengths of warm-dry conditions and stratification had significantly higher germination rates compared with seeds exposed for shorter time periods. Elaiosome removal had little effect on percent germination, but indirect evidence suggests that elaiosomes increased vulnerability to pathogen attack. We recommend future efforts to germinate V. pedata seeds should begin by removing elaiosomes and exposing seeds to warm-dry conditions for 8 to 12 wk and then stratifying them for 8 to 12 wk.

Advantages of Seed Dispersal for a Myrmecochorous Temperate Forest Herb

The advantages of ant-mediated seed dispersal for myrmecochorous plants have often been framed in the context of directed dispersal and predator avoidance. Underlying and intertwining themes in these frameworks are the services of (a) moving seeds away from parent plants, (b) placing seeds in safe and ideal locations and occasionally, (c) removing elaiosomes to thwart detection by seed predators. These services are rarely simultaneously investigated from an experimental standpoint to determine which may be most important. Here, we conducted a factorial-designed field experiment to test how survival of seeds of a myrmecochrous forest herb, Asarum canadense (wild ginger), in two forest sites in southwestern Ohio, USA, was affected by the following treatments: distance from parent plant, seed burial, elaiosome removal, and their interactions. We found that when placed in artificial depots consisting of 10 seeds, only seed burial significantly aided seed survival. We supplemented this by conducting a laboratory experiment in which mice were given choices of trays containing either buried seeds with elaiosomes or without elaiosomes at densities higher than those of our field experiment and within the realm of those contained in ant nests. Mice consumed more mass of seeds with elaiosomes, suggesting that elaiosome removal may be advantageous in this context. When taken together, our results highlight the importance of seed burial and elaiosome removal for seed survival of a myrmecochorous forest herb. Though not specifically addressed in our study, the combination of these two services may positively contribute to later life history stages (e.g., seedlings) and population persistence of myrmecochorous plants and may ultimately reveal the importance of other services (e.g., short-distance seed dispersal) and their interactions.

Effects of seed passage through slugs on germination

Seed dispersal by invertebrates is mostly external (e.g. by ants). However, internal dispersal (endozoochory) seems to be uncommon due to size limitations. Slugs are generalist herbivores and increasing evidence suggests that they often disperse seeds. Nevertheless, we know very little on the consequences for plant recruitment. Here, we assess the effect of slug seed passage on germination and early seedling establishment of a set of nine common plant species with limited dispersal capabilities (unassisted or ant dispersed). Germination trials were performed under natural conditions (NW of Spain). Size was a clear limitation for seed ingestion: smaller seeds were eaten more readily, whereas only the largest slugs could swallow the largest seeds. All ingested seeds were voided undamaged. Only not-ingested seeds (the biggest) were damaged, with chewing marks in the surface and 0.8% (N = 250) were broken. In some cases, slugs ate the elaiosomes but discarded the seeds. Slug seed passage had an overall positive effect on total germination and sped it up in two species. Elaiosome removal by slugs had also a positive effect in Ulex europaeus seeds (+160%). However, slugs had no effect on early seedling survival and growth of the study species. Our results show that slugs are effective dispersers in terms of seed treatment in the digestive track. However, according to their reduced movement range (in the range of tens of metres; as shown by other studies), they can only provide rather limited dispersal as compared to vertebrate dispersers. This can be nonetheless significant for species with limited dispersal, e.g. unassisted and ant-dispersed plants, for which they act as non-standard dispersers.

Influence of elaiosome on postdispersal dynamics of an ant-dispersed plant

Specialized myrmecochorous plants bear an elaiosome attached to the seed. Ants benefit from food provided by this appendage and plants get their seeds eventually dispersed. Aside from the benefits conferred by seed dispersal, we hypothesize that the influence of the elaiosome might extend to later life history stages such as emergence or survival, but few studies have examined rigorously such delayed effects on seed and seedling dynamics. This paper tests this hypothesis for the ant-dispersed herb Helleborus foetidus. Presence or lack of the elaiosome had some interesting delayed influences. Specifically, our results show that elaiosome removal not only enhanced seedling emergence, but also reduced cumulative long-term seed predation. The combination of these two effects, together with the inherent positive effect of the elaiosome on seed dispersal, highlights the ecological and evolutionary importance of myrmecochorous systems.

Seed Dispersal by Ants in the Semi-arid Caatinga of North-east Brazil

Myrmecochory is a conspicuous feature of several sclerophyll ecosystems around the world but it has received little attention in the semi-arid areas of South America. This study addresses the importance of seed dispersal by ants in a 2500-km(2) area of the Caatinga ecosystem (north-east Brazil) and investigates ant-derived benefits to the plant through myrmecochory. Seed manipulation and dispersal by ants was investigated during a 3-year period in the Xingó region. Both plant and ant assemblages involved in seed dispersal were described and ant behaviour was characterized. True myrmecochorous seeds of seven Euphorbiaceae species (i.e. elaiosome-bearing seeds) were used in experiments designed to: (1) quantify the rates of seed cleaning/removal and the influence of both seed size and elaiosome presence on seed removal; (2) identify the fate of seeds dispersed by ants; and (3) document the benefits of seed dispersal by ants in terms of seed germination and seedling growth. Seed dispersal by ants involved one-quarter of the woody flora inhabiting the Xingó region, but true myrmecochory was restricted to 12.8 % of the woody plant species. Myrmecochorous seeds manipulated by ants faced high levels of seed removal (38-84 %) and 83 % of removed seeds were discarded on ant nests. Moreover, seed removal positively correlated with the presence of elaiosome, and elaiosome removal increased germination success by at least 30 %. Finally, some Euphorbiaceae species presented both increased germination and seedling growth on ant-nest soils. Myrmecochory is a relevant seed dispersal mode in the Caatinga ecosystem, and is particularly frequent among Euphorbiaceae trees and shrubs. The fact that seeds reach micro-sites suitable for establishment (ant nests) supports the directed dispersal hypothesis as a possible force favouring myrmecochory in this ecosystem. Ecosystems with a high frequency of myrmecochorous plants appear not to be restricted to regions of nutrient-impoverished soil or to fire-prone regions.

Dispersal by ants inCentaurea corymbosa(Asteraceae): What is the elaiosome for?

AbstractThis paper reports on different observations and experiments examining the role of ants in the seed dispersal of the rare and endemic speciesCentaurea corymbosa. Direct observations of seed manipulation by ants in natural populations showed that dispersal distances are very limited, and many ants did not disperse seeds at all. Cafeteria experiments failed to demonstrate: (i) that the elaiosome represents the attractive part of the achene; and (ii) that seeds ofEuphorbia characias,a common species occurring in the same habitat, are more attractive than achenes ofC. corymbosadespite a 10‐fold difference in elaiosome size. However, ants show a foraging behavior to collect seeds ofC. corymbosabecause seed removal is greater at the foot of a fruiting plant than further away. Experiments in controlled conditions were also carried out to investigate the secondary benefits of seed manipulation by ants. Two independent experiments showed that, in contrast to many other myrmecochorous species, elaiosome removal decreases germination rate. Finally, the effects of burial at low depth (2 cm) on seed emergence are limited; however, as ants rarely move seeds to their nest, this secondary benefit of myrmecochory is unlikely. Therefore, it can be concluded that the functional role of an elaiosome in this species is not evident. However, ants clearly contribute to seed dispersal inC. corymbosa.

Ant behaviour and seed morphology: a missing link of myrmecochory

Seed dispersal by ants (myrmecochory) is mediated by the presence of a lipid-rich appendage (elaiosome) on the seed that induces a variety of ants to collect the diaspores. When seeds mature or fall onto the ground, these ant species transport them to their nest. After eating the elaiosome, the seed is discarded in nest galleries or outside, in the midden or farther away, where seeds can potentially germinate. The final location of seeds with their elaiosomes removed was evaluated to assess the importance of possible handles (structures that ants can grasp to carry) in transporting ants during re-dispersal experiments of seeds from nests of six species of ants. The results indicate that seeds remained within the nest because the ants were not able to transport them out of the nest. As a consequence of the elaiosome being removed, small ant species could not take Euphorbia characias seeds out of their nests. Only large ant species could remove E. characias seeds from their nests. Attaching an artificial handle to E. characias seeds allowed small ant species to redistribute the seeds from their nests. On the other hand, Rhamnus alaternus seeds that have a natural handle after the elaiosome removal were removed from the nests by both groups of ant species. If a seed has an element that acts as a handle, it will eventually get taken out of the nest. The ants' size and their mandible gap can determine the outcome of the interaction (i.e. the pattern of the final seed shadow) and as a consequence, could influence the events that take place after the dispersal process.

CRYPTIC CONSEQUENCES OF A DISPERSAL MUTUALISM: SEED BURIAL, ELAIOSOME REMOVAL, AND SEED-BANK DYNAMICS

In moving seeds from one location to another, dispersers define the ecological context that a plant will experience throughout its lifetime. Because seed deposition sites may benefit one plant life cycle stage but not others, dispersal may give rise to a conflict between a plant's dispersal needs (e.g., predator escape) and its requirements for successful establishment (e.g., suitable habitat). In this study, we assessed the effects of two com- ponents of seed dispersal by ants (seed burial depth and elaiosome removal) at several stages during the recruitment of Leucospermum truncatulum, an ant-dispersed plant from the fynbos shrublands of South Africa. A seed-predator exclusion experiment revealed that the removal of elaiosomes significantly reduced rodent predation on seeds buried 1 cm deep and increased the viability of seeds that were not consumed. In contrast, we found that elaiosomes had no effect on the probability of a living seed emerging as a seedling. In a seed burial depth experiment in which predators were not excluded, deeper burial significantly enhanced seed survival, but this benefit came at the expense of reduced seedling emergence, delayed emergence, and smaller cotyledon size. Despite the potential importance of these seedling characteristics, elaiosomes and burial depth had no significant effect on seedling survival through the first year of this study. In contrast, burial depth had strong positive effects on the fraction of seeds that persisted in the seed bank. Although dormant individuals may die before germinating and reproducing, those that persist at greater soil depths can play a crucial role in rescuing populations from local extinction in unpredictable environments. Given the extreme variability in fire frequency in fynbos, the net effect of seed dispersal by ants on plant populations will depend on how temporal fluctuations in fire regimes influence cost-benefit thresholds related to seed dormancy and seed mortality.

Effects of the Argentine ant Linepithema humile on seed dispersal and seedling emergence of Rhamnus alaternus

We studied influence of the Argentine ant's Linepithema humile occurrence on seed dispersal of Rhamnus alaternus (Rhamnaceae). Rhamnus alaternus is a fleshy fruit plant dispersed primarily by birds; the seeds have an elaiosome attractive to ants. The observations were made in two study plots of Mediterranean cork‐oak forests (one invaded and the other not invaded by L. humile) over two years. For R. alaternus, presence of L. humile was associated with of the following: reduction of seed transport to ant nests (80.2% of seed offered were removed in non‐invaded vs 7.1% in invaded area), a shorter seed dispersal distance (mean=90.2 cm in non‐invaded vs 1.1 cm in invaded area), increase in seed retention time on the soil surface (median time in non‐invaded was 50 vs 209.2 min in invaded area) and increased vulnerability to predation. In addition there was lower probability of seedling emergence, due to little elaiosome removal from the seeds (82.0% of emergence for seeds without elaiosome and 57.3% for seeds with elaiosome). These results, similar to findings obtained in South African fynbos, confirm that the Argentine ant invasion can strongly affect ecosystem processes in the Mediterranean biome.

Ant Dispersal of Croton priscus (Euphorbiceae) Seeds in an Tropical Semideciduous Forest in Southeastern Brazil

Seed dispersal of C. priscus was studied in a semideciduous forest in S.E. Brazil. C. priscus is a pioneer tree, with abundant capsules containing three elaiosome-bearing seeds. The seeds are explosively dispersed and the mean ballistic dispersal distance for two trees were 3.2 and 3.4 m. The explosive ejection of seeds is followed by ant exploitation. Eleven ant species were attracted to the elaiosomes of the seeds, but only two species regularly removed seeds. On average, Atta sexdens and Pheidole sp. 1 move seeds 2.5 and 1.0 m, respectively. The ants usually deposit the seeds in the nest. The seed removal rate was 88 percent (N = 100) over the first 24 hr of exposure. Our results indicate that elaiosome removal by ants probably does not improve germination rates in C. priscus. Seeds without elaiosomes and seedlings of C. priscus were frequent on refuse piles of ant nest in the study area, suggesting that transport of the seeds by Attini and Pheidolini may provide beneficial effects in the Croton system.

Selective Advantages to Hemi-Parasitic Annuals, Genus Melampyrum, of a Seed-Dispersal Mutualism Involving Ants: II. Seed-Predator Avoidance

Field experiments were used to assess the importance of third species antagonists, in this case rodent seed-predators, in driving the evolution of seed dispersal by ants in the genus Melampyrum. Daytime and nighttime seed-removal frequencies were determined by placing seeds so that 1) ants and rodents had access, 2) only ants had access, 3) only rodents had access, and 4) neither ants nor rodents had access. Experiments were conducted with Melampyrum populations of three different species at four sites, two in the U.S. (M. lineare in Maine and Michigan) and two in Switzerland (M. arvense and M. silvaticum). Morning versus evening fruit dehiscence and the effect of elaiosome removal on seed-attractiveness to ants were also investigated

Effect of Diaspore Characteristics on Removal of Seeds Adapted for Dispersal by Ants

We investigated the role of ant behavior as a selective influence on the presentation and morphology of elaiosome—bearing seeds in Australian sclerophyll vegetation by manipulating characteristics of natural and artificial diaspores. We compared the response to these diaspores of three seed—removing ant species, two of which (Rhytidoponera "metallica" and Aphaenogaster longiceps), produce more favorable seed fates than the third species (Pheidole sp. 1). We measured the effect on removal rate of diaspore arrangement (degree of clumping), elaiosome removal, diaspore size (i.e., mass), elaiosome/load ratio, and composition of both the elaiosome and seed. Clumped seeds were removed significantly faster than single seeds by Pheidole sp. 1, a group forager. A. longiceps, a solitary forager, removed single seeds faster while R. "metallica" removed single and clumped seeds at the same rate. The presence of elaiosomes on seeds increased removal rates, especially by A. longiceps and R. "metallica." Both A. longiceps and R. "metallica" responded positively to elaiosome/load ratio while Pheidole sp. 1 responded mainly to diaspore size. These species—specific responses were such that diaspores with high elaiosome/seed ratios are more likely to be removed by A. longiceps or R. "metallica" than by Pheidole sp. 1. Diaspore characteristics other than size had inconsistent effects on removal rates. The differential response of the ant species to such characteristics as seed arrangement and elaiosome/seed ratios demonstrates the way in which ant behavior may have been an important selective force in the evolution and maintenance of myrmecochory.

Seed Predation by Rodents on Three Ant‐Dispersed Plants

Seed predation by small mammals has been proposed as one selective force in the evolution of ant—dispersal (myrmecochory) in many herbaceous plants of mesic deciduous forests. Three myrmecochorous species, Asarum canadense, Jeffersonia diphylla, and Sanguinaria canadensis, were studied in the Monongahela National Forest, West Virginia, USA, to (a) assess the impact of seed predators on seed mortality, (b) compare seed removal rates when ants were present vs. absent, and (c) evaluate the effects of elaiosome removal, seed burial, and doubling seed number per depot on rates of seed predation. Seed predators, especially rodents, cause more mortality among these woodland herbs than previously thought. Predispersal seed predation by rodents destroyed 24% and 47% of the seed crops of A. canadense and J. diphylla, respectively. The proportions of A. canadense seeds lost to predators varied among sites. Sanguinaria canadensis also suffered seed predation before capsules dehisced. Peromyscus leucopus was the most common seed predator. In exclosure experiments, seed predators removed 70% of the A. canadense seeds when dispersal by ants was prevented, but only 24—39% of the seeds suffered predation when ants were allowed access. Seed predators removed 84% of the S. canadensis seeds when ants were excluded, but 13—43% were lost when also exposed to ants. These estimated minimal proportions of seeds lost to predators when ants were allowed access differed between two study sites, but myrmecochory clearly reduced seed predation at parent plants. In laboratory experiments, P. leucopus located buried A. canadense and S. canadensis seeds less frequently than seeds on the surface (67.5% vs. 100%). Consumption of buried seeds by rodents was reduced when elaisomes were removed, as would be done by ants in natural conditions. Increasing the detectability of seeds through adding olfactory cues or doubling seed number per depot did not increase the frequency of predation, because mice were able to locate depots without these additional cues.

THE FATE OF VIOLA SEEDS DISPERSED BY ANTS

Experimental plantings of the seeds of the two species Viola odorata and V. hirta were carried out to determine relative importance of three effects of myrmecochory: 1) clumping of seeds, 2) scarification of the testa and elaiosome removal, and 3) relocation into ant nests. The study site was a beech‐larch wood in southern England. Data show that clumping slightly reduces seedling emergence, scarification and elaiosome removal slightly enhances it, while the nest environment significantly increases the rate of seedling emergence. Only the last effect is statistically significant. Seedlings from nests have larger first adult leaves. The possible impact of ant manipulation of seeds on seedling recruitment into myrmecochorous populations is discussed.