Ectomycorrhizal synthesis on seedlings of Afzelia quanzensis Welw. using various types of inoculum

Ectomycorrhizal synthesis on seedlings of Afzelia quanzensis was initiated in the greenhouse and in the field using basidiospores or soil inoculum originating from fungi associated with adult trees of A. quanzensis, Brachystegia microphylla, B. spiciformis, and Julbernardia globiflora. Of the spore inocula used, only a Pisolithus sp. associated with adult A. quanzensis formed mycorrhizae. Seedlings raised in contact with all soil inocula formed mycorrhizae; however, the mycorrhizal types formed differed between soil inoculum used in the greenhouse and soil inoculum directly used in the field. A. quanzensis has a low specificity for mycorrhizal association. The concepts of ectomycorrhizal succession are also applicable to African savanna ecosystems.     

Mixotrophy of Platanthera minor, an orchid associated with ectomycorrhiza-forming Ceratobasidiaceae fungi

? We investigated the fungal symbionts and carbon nutrition of a Japanese forest photosynthetic orchid, Platanthera minor, whose ecology suggests a mixotrophic syndrome, that is, a mycorrhizal association with ectomycorrhiza (ECM)-forming fungi and partial exploitation of fungal carbon. ? We performed molecular identification of symbionts by PCR amplifications of the fungal ribosomal DNA on hyphal coils extracted from P. minor roots. We tested for a (13)C and (15)N enrichment characteristic of mixotrophic plants. We also tested the ectomycorrhizal abilities of orchid symbionts using a new protocol of direct inoculation of hyphal coils onto roots of Pinus densiflora seedlings. ? In phylogenetic analyses, most isolated fungi were close to ECM-forming Ceratobasidiaceae clades previously detected from a few fully heterotrophic orchids or environmental ectomycorrhiza surveys. The direct inoculation of fungal coils of these fungi resulted in ectomycorrhiza formation on P. densiflora seedlings. Stable isotope analyses indicated mixotrophic nutrition of P. minor, with fungal carbon contributing from 50% to 65%. ? This is the first evidence of photosynthetic orchids associated with ectomycorrhizal Ceratobasidiaceae taxa, confirming the evolution of mixotrophy in the Orchideae orchid tribe, and of ectomycorrhizal abilities in the Ceratobasidiaceae. Our new ectomycorrhiza formation technique may enhance the study of unculturable orchid mycorrhizal fungi.     

Introduction of asymbiotically propagated seedlings of <Emphasis Type="Italic">Cephalanthera falcata</Emphasis> (Orchidaceae) into natural habitat and investigation of colonized mycorrhizal fungi

Asymbiotic seedling propagation and introduction of seedlings into a natural habitat were achieved for Cephalanthera falcata. For immature seeds collected 65 days after pollination, high germination rate (av. 50%) was achieved on Hyponex agar medium plates. Root development occurred in about 10% of the protocorms 5 months after seed sowing. Rooted protocorms were transferred to a culture bottle containing 100 ml of the Hyponex agar medium and incubated continually. In about 30% of the transferred individuals, shoot height reached 1.5–2 cm 8 months after the transfer. After acclimatization in wet vermiculite at 4°C for 6 months, 135 individuals were planted in a natural stand of C. falcata in mid February 2001. Shoot appearance rate was 44.4% at the first year and flowering was noted in some plants. At the fifth year, shoots with an average height of 21.6 cm still appeared in four plants, and flowering was noted in three of them. Colonization of mycorrhizal fungi was examined in two of them as well as one wild plant, in which the mycorrhizal fungi were identified to be in Thelephoraceae or Russulaceae. These fungi are known to form ectomycorrhiza with trees, and thus a tripartnership symbiosis consisting of C. falcata, mycorrhizal fungi and trees was suggested. The involvement of ectomycorrhizal fungi might be the reason for the low survival rate in the field experiment, because the distribution of ectomycorrhizal fungi relevant to this orchid is assumed to be uneven. The possibility of introducing artificially propagated orchids into natural habitats was discussed.     

Distribution of ectomycorrhizal fungi in a Chamaecyparis obtusa stand at different distances from a mature Quercus serrata tree

Ectomycorrhizal fungal distributions at different distances from one mature Quercus serrata tree were demonstrated in a Japanese cypress stand. After 4 months for field-planted and 3 months for laboratory-incubated Q. serrata seedlings, they were evaluated ectomycorrhiza formations. For the field-planted seedlings, molecular discrimination was conducted to clarify the species diversity of ectomycorrhizal fungi. Ectomycorrhiza formation was confirmed at all distances in both methods. However, the formation and associating fungal species were decreased with increasing distance. These results indicate that the density and diversity of ectomycorrhizal fungi decrease rapidly within several tens of meters from arbuscular mycorrhizal forest edges.     

Forest microsite effects on community composition of ectomycorrhizal fungi on seedlings of Picea abies and Betula pendula

Niche differentiation in soil horizons, host species and natural nutrient gradients contribute to the high diversity of ectomycorrhizal fungi in boreal forests. This study aims at documenting the diversity and community composition of ectomycorrhizal fungi of Norway spruce ( Picea abies ) and silver birch ( Betula pendula ) seedlings in five most abundant microsites in three Estonian old-growth forests. Undisturbed forest floor, windthrow mounds and pits harboured more species than brown- and white-rotted wood. Several species of ectomycorrhizal fungi were differentially represented on either hosts, microsites and sites. Generally, the most frequent species in dead wood were also common in forest floor soil. Ordination analyses suggested that decay type determined the composition of EcM fungal community in dead wood. Root connections with in-growing mature tree roots from below affected the occurrence of certain fungal species on seedling roots systems in dead wood. This study demonstrates that ectomycorrhizal fungi differentially establish in certain forest microsites that is attributable to their dispersal and competitive abilities. Elevated microsites, especially decayed wood, act as seed beds for both ectomycorrhizal forest trees and fungi, thus affecting the succession of boreal forest ecosystems.     

Ectomycorrhiza synthesis and basidiome formation of an orchid symbiont of the genus Thelephora on Quercus serrata

We induced basidioma formation of a fungus belonging to the Thelephoraceae that was isolated from the orchid Cephalanthera falcata. The mycobiont was isolated from root, cultured on modified Melin-Norkrans medium, and then inoculated onto fine roots of a Quercus serrata (Fagaceae) seedling. After observation of ectomycorrhiza formation, the Q. serrata seedling was grown in a pot. Thirty-six mo after ectomycorrhiza formation, basidioma formation was confirmed at the bottom of the pot. From comparisons in morphological characteristics between the mycobiont and known related Thelephoraceae species, and sequence similarities of internal transcribed spacer region in ribosomal DNA, we identified the mycobiont as Thelephora ellisii sensu lato in Thelephoraceae (Basidiomycota). Phylogenetic analysis indicated that the related sequences came from ectomycorrhizae of trees of the Salicaceae, Pinaceae, and Fagaceae distributed in East Asia, the USA, central Africa, and Europe.     

Beech carbon productivity as driver of ectomycorrhizal abundance and diversity

We tested the hypothesis that carbon productivity of beech ( Fagus sylvatica ) controls ectomycorrhizal colonization, diversity and community structures. Carbon productivity was limited by long-term shading or by girdling. The trees were grown in compost soil to avoid nutrient deficiencies. Despite severe limitation in photosynthesis and biomass production by shading, the concentrations of carbohydrates in roots were unaffected by the light level. Shade-acclimated plants were only 10% and sun-acclimated plants were 74% colonized by ectomycorrhiza. EM diversity was higher on roots with high than at roots with low mycorrhizal colonization. Evenness was unaffected by any treatment. Low mycorrhizal colonization had no negative effects on plant mineral nutrition. In girdled plants mycorrhizal colonization and diversity were retained although ¹⁴C-leaf feeding showed almost complete disruption of carbon transport from leaves to roots. Carbohydrate storage pools in roots decreased upon girdling. Our results show that plant carbon productivity was the reason for and not the result of high ectomycorrhizal diversity. We suggest that ectomycorrhiza can be supplied by two carbon routes: recent photosynthate and stored carbohydrates. Storage pools may be important for ectomycorrhizal survival when photoassimilates were unavailable, probably feeding preferentially less carbon demanding EM species as shifts in community composition were found.     

外生菌根研究及应用的回顾与展望

简要回顾了一百多年来外生菌根研究史;综述了外生菌根资源调查。分类鉴定,生态,生理,分子生物学以及生物技术研究与应用诸方面的阶段性成果和进展,通过对外生菌根研究与应用现状的归纳与分析,就我国菌根研究与应用等方面存在的主要问题提出了以下4点建议;1,加强菌根资源的系统调查;确认对应植物属种,进行编目与建立数据库以及菌根DNA文库。2,采集与收集菌根真菌,进行分离,培养,繁育与保藏,建立菌根真菌菌种库和DNA文库,3,加强菌根技术研究,侧重研究造林树种菌根化育苗和造林的新技术,新工艺,4,改革传统的育苗与造林的方式,方法,选育对应的优良菌根真菌菌株应用于育苗造林;制定相关的政策,法规以规范和推广菌根技术。     

Belowground ectomycorrhizal communities in three Norway spruce stands with different degrees of decline in the Czech Republic

We investigated the ectomycorrhizal communities on the roots of adult trees and seedlings associated with three Norway spruce stands in the Czech Republic using morphological and molecular tools. The stands had different degrees of forest decline due to air pollution. The aims of the study were to obtain information about the belowground ectomycorrhizal community in a heavily damaged spruce forest and to assess whether missing ectomycorrhizal fungal partners could be one of the reasons for the observed lack of regeneration. The ectomycorrhizal species richness on the roots of adult trees was significantly lower in the heavily damaged site Mumlavska hora than in the other two, but less drastically so than that found in a fruitbody survey. The roots of adult trees and seedlings were fully mycorrhizal at this site although they were less species-rich. The most abundant ectomycorrhizal species on the root system of adult trees in all three forest stands was Tylospora fibrillosa, a member of the athelioid clade. It made up over 60% of root tips in Mumlavska hora and its proportion was at least twice that in the other two sites. This species was also an efficient colonizer of roots from seedlings, in particular, in the most damaged site. The different soil properties in this site may have caused the observed differences in the ectomycorrhizal species richness and composition. For example, cation exchange capacity and soil base saturation were lower and the soil more often saturated. However, the number of living trees and their defoliation status may well directly impact the ectomycorrhizal species composition by presumably affecting the amount of carbon delivered to the symbiotic fungal partners. Athelioids and thelephoroids are an important component of the belowground ectomycorrhizal community in most temperate and boreal forests, but the role they play might even be more crucial in stressed forest ecosystems. Based on our results, we suggest that factors other than missing ectomycorrhizal inoculum constrain natural regeneration in the heavily damaged site Mumlavska hora.     

Mycoheterotrophic growth of Cephalanthera falcata (Orchidaceae) in tripartite symbioses with Thelephoraceae fungi and Quercus serrata (Fagaceae) in pot culture condition

Mixotrophy, obtaining carbon by mycoheterotrophy and photosynthesis, has been suggested in Cephalanthera species (Orchidaceae) by analyses on stable isotopes of carbon. In this study, we examined the growth of Cephalanthera falcata in pot cultured tripartite symbioses with Thelephoraceae fungi and Quercus serrata. Mycorrhizal fungi were isolated from roots of C. falcata in natural habitats. Two fungal isolates identified as Thelephoraceae were cultured and inoculated to fine roots of non-mycorrhizal seedlings of Q. serrata (Fagaceae). After the ectomycorrhizal formation, non-mycorrhizal seedlings of C. falcata were co-planted. The pots with tripartite symbioses were cultured in greenhouse for 30 months, and growth of C. falcata seedlings was examined. Fresh weight of C. falcata seedlings was significantly increased by the tripartite symbioses even in those with no shoot, thus providing further evidence for the mycoheterotrophic nature of this orchid. The achievement of seedling culture in tripartite symbioses would be valuable for conserving many forest orchids and for conducting experiments to understand their physiology and ecology.     

Quantities and types of ectomycorrhizal and endophytic fungi associated with Betula platyphylla var. japonica seedlings during the initial stage of establishment of vegetation after disturbance

Ectomycorrhizal and endophytic fungi of Betula platyphylla Sukatchev var. japonica Hara seedlings were investigated by bioassay using soils from sites where the surface layer had been removed by destructive disturbances. Soil samples were taken from sites A, B, C and D, where 1, 2–3, 4–5, and 7–8 years, respectively had passed since disturbance. Naturally regenerated B. platyphylla var. japonica seedlings grew at sites C and D, but not at sites A or B. The percentages of ectomycorrhizal formation in seedlings were significantly lower in the soils from site A (4%) and site B (13%), compared to those in the soils from site C (53%) and site D (37%). The numbers of ectomycorrhizal morphologic types in sites A, B, C, and D were eight, five, one, and seven, respectively. The same dominant type of ectomycorrhiza was found in sites C and D, and this type was different from those in sites A and B. The frequencies of colonization of seedling roots by endophytic fungi, especially Mycelium radicis atrovirens Melin (MRA) in soils from sites A and B were 31 and 33%, respectively; these frequencies were significantly higher than those for site C (0%) and site D (2%). During the initial stage of establishment of vegetation following disturbance, the quantities and types of ectomycorrhizal fungi in the field that have the potential to associate with B. platyphylla var. japonica might rapidly change after invasion of the host plant. Ectomycorrhizal fungi seemed to compete with endophytic MRA fungi for colonization of the roots of B. platyphylla var. japonica seedlings.     

Seedling establishment of deciduous trees in various topographic positions

Abstract. We investigated the effect of topography‐related environmental factors (i.e., ground‐surface stability and soil moisture) on seedling establishment of 8 deciduous tree species. A field experiment was carried out using canopy species, which were classified into 3 groups based on the spatial distribution of adult trees (ridge, slope and valley). Demographic parameters were compared among species during the early stage of seedling establishment among 3 topographic positions in combination with gap and canopy conditions. The percentage of emerging seedlings tended to be lower on the ridge irrespective of the adult topographical distribution patterns. There was no clear trend in seedling emergence among the species groups classified by their spatial distribution. Seedling survival during 2 growing seasons was significantly different among species, topographic positions and light conditions. On the ridge, seedlings of the species dominating ridge tops had greater survival than those of other species, probably due to differences in demand for soil moisture. On the slope, frequent physical damage caused by surface material movement was observed and some species showed greater adaptability to the disturbed slope habitat. Survival of all seedlings was highest in the valley plots. Light conditions were the critical factor for seedling survival in some species. The results of this study suggest that topography creates diverse habitats for the establishment of tree seedlings. In addition to soil moisture, surface material movement may be a significant factor affecting seedling establishment.     

Ectomycorrhizas of Cercocarpus ledifolius (Rosaceae)

? Premise of the study: Woody species in the Rosaceae form ectomycorrhizal associations, but the fungal symbionts are unknown. The species of fungi determine whether host plants are isolated from other ectomycorrhizal species in the plant community or linked with other trees through mycorrhizal networks. In this study we identified the fungi that form ectomycorrhizas with Cercocarpus ledifolius (curl-leaf mountain mahogany). ? Methods: Soil samples were collected under canopies of C. ledifolius. Ectomycorrhizas were described by morphology and by DNA sequences of the ITS region. Host species were confirmed by rbcL sequences. ? Key results: Sixteen species of fungi were identified from ectomycorrhizas of Cercocarpus ledifolius. The ectomycorrhizal community was distinguished by the presence of a Geopora species situated in the G. arenicola clade and by the absence of Rhizopogon, suilloids, and Sebacinales. Of the species on C. ledifolius, two also occurred on trees of Quercus garryana var. breweri and four on Arctostaphylos sp. ? Conclusions: The presence of fungal species in common with other ectomycorrhizal hosts shows that C. ledifolius, Q. garryana var. breweri, and Arctostaphylos species could be linked by a mycorrhizal network, allowing them to exchange nutrients or to share inoculum for seedling roots and new fine roots. Single-host fungi limited to C. ledifolius may improve resource acquisition and reduce competition with other ectomycorrhizal hosts. The finding of a Geopora species as a frequent mycobiont of C. ledifolius suggests that this fungus might be appropriate for inoculating seedlings for habitat restoration.     

Density‐dependent Survival in Seedlings Differs among Woody Life‐forms in Tropical Wet Forests of a Caribbean Island

Negative density dependence contributes to seedling dynamics in forested ecosystems, but the relative importance of this factor for different woody plant life‐forms is not well‐understood. We used 1 yr of seedling survivorship data for woody seedlings in 17 different plots of lower to mid‐montane rain forests on the island of Dominica to examine how seedling height, abiotic factors, and biotic factors such as negative density dependence are related to seedling survival of five different life‐forms (canopy, midstory, and understory trees; shrubs; and lianas). Across 64 species, taller seedlings in seedling plots with higher canopy openness, greater seedling density, lower relative abundance of conspecific seedlings, and lower relative abundance of conspecific adults generally had a greater probability of surviving. Height was the strongest predictor of seedling survival for all life‐forms except lianas. Greater seedling density was positively related to survival for canopy and midstory trees but negatively related to survival for the other life‐forms. For trees, the relative abundance of conspecific seedling and adult neighbors had weak and strong negative effects on survival respectively. Neither shrub nor liana seedling survival was affected by the relative abundance of conspecific neighbors. Thus, negative density dependence is confirmed as an important structuring mechanism for tree seedling communities but does not seem to be important for lianas and shrubs in Dominican rain forests. These results represent the first direct assessment of controls on seedling survival of all woody life‐forms – an important step in understanding the dynamics and structure of the entire woody plant community.     

Developmentally regulated proteins during differentiation of root system and ectomycorrhiza in Scots pine (Pinus sylvestris) with Suillus bovinus

Total and radiolabelled proteins from Pinus sylvestris roots, ectomycorrhiza and the ectomycorrhizal fungus Suillus bovinus , were analyzed after separation by 2‐D gel electrophoresis. The purpose was to address the contribution of individual proteins to the development of ectomycorrhiza. In Pinus sylvestris , ectomycorrhiza forms only in the short roots and therefore special attention was paid to the proteins of short roots before formation of ectomycorrhiza. A main result, from comparisons of protein amounts in main and lateral root tips and short roots, was that the specialized growth pattern of short roots is associated with the production of five short root‐specific proteins, and that several proteins of the main and lateral roots are repressed in short roots. At the morphologically different stages of the ectomycorrhiza, only few changes appeared in the amounts of the host and the symbiont proteins. Only one ectomycorrhiza‐specific protein could be distinguished.     

Salinity effects on germination,growth, and seed production of the halophyte Cakile maritima

The growth ofEucalyptus regnans seedlings in forest soil is enhanced when it has been air-dried. In undried forest soil seedlings grow poorly and develop purple coloration in the foliage, indicating P deficiency. This paper reports the results of pot experiments designed to investigate the relationship between growth and P acquisition, ectomycorrhizal infection and age of seedlings grown in air-dried and undried soil. The effect on seedling growth of their inoculation with air-dried or undried soil or with ectomycorrhizal roots from plants growing in air-dried or undried soil was also investigated. Ectomycorrhizal root tips were detected in 3-week-oldE. regnans seedlings in both air-dried and undried soil, and from then on the frequency of ectomycorrhizal root tips increased rapidly. In air-dried soil, seedlings were fully ectomycorrhizal at 9 weeks, and the occurrence of maximum ectomycorrhizal infection coincided with enhanced P acquisition and the initiation of rapid seedling growth. In undried forest soil, seedling growth remained poor, even though the seedlings had well-developed ectomycorrhizae and the incidence of ectomycorrhizal root tips was the same as in air-dried soil. The dominant ectomycorrhizae in airdried soil were associated with an ascomycete fungus, whereas in undried, undisturbed soil they were commonly associated with basidiomycete fungi. Inoculation of sterile soil/sand mix with washed ectomycorrhizal roots from air-dried soil increased the P acquisition and growth of the seedlings significantly compared with controls, whereas ectomycorrhizal inocula from undried soil had no effect on seedling growth, although both inocula resulted in a similar incidence of ectomycorrhizal root tips. Similarly, addition of a small amount of air-dried soil into sterile soil/sand mix resulted in a significantly greater increase in the P content and dry weight of the seedlings, compared with the control, than addition of undried soil. In both treatments, the incidence of ectomycorrhial root tips was similar. As (i) the differentiation in seedling growth between air-dried and undried soil occurred after seedlings became ectomycorrhizal, (ii) the dominant ectomycorrhizae in air-dried soil were different from those in undried soil, and (iii) inocula from air-dried soil, but not from undried soil, stimulated seedling growth in sterile soil/sand mix, it is concluded that development of particular ectomycorrhizae may be involved in seedling growth stimulation and enhanced P acquisition associated with air drying of forest soil.     

The influence of culture conditions on mycorrhiza formation between the ectomycorrhizal fungus Pisolithus sp. and Afzelia africana Sm. seedlings

Interactions between an isolate of the ectomycorrhizal fungus Pisolithus sp. and Afzelia africana Sm. seedlings were studied at the structural and ultrastructural levels. Several different conditions were tested with or without sugar and in a sterile or nonsterile medium. In the growth cabinet, the A. africana/Pisolithus sp. interactions did not produce ectomycorrhizas. A fungal sheath was formed but no Hartig net, and an unusual host epidermal cell wall was observed. Hyphae of Pisolithus sp. induced modifications of epidermal cells of 15-day-old A. africana seedlings indicative of non-mycorrhizal interactions, such as wall thickening, wall ingrowth, papillae formation, degraded host wall material and the presence of intracellular hyphae. Wall ingrowth consisted of depositions of host cell wall materials giving a positive reaction for polysaccharides; however, wall thickenings and papillae showed no homogeneous reactions for polysaccharides. In glasshouse conditions, inocula of Pisolithus sp. in the form of spores or mycelia entrapped in peat-vermiculite added to sterilized soil produced typical ectomycorrhizae only with 6-month-old A. africana seedlings. Under these conditions, no conspicuous cell wall reactions occurred on A. africana roots. The results demonstrate that the establishment of an association between an ectomycorrhizal fungus and a potential host plant is strongly influenced by seedling age and/or environmental conditions. Therefore, in vitro synthesis is not a conclusive demonstration of a symbiotic relationship.     

Soil burrowing Muscina angustifrons (Diptera: Muscidae) larvae excrete spores capable of forming mycorrhizae underground

Muscina angustifrons (Diptera: Muscidae) is a mycophagous species that exploits a variety of fungi, including ectomycorrhizal fungi. Larvae of this species have been shown to feed on sporocarps (including spores), and full-grown larvae leave sporocarps and pupate 0–6?cm below the soil surface. In this study, we examined whether M. angustifrons larvae are capable of transporting ectomycorrhizal fungal spores and enhancing ectomycorrhiza growth on host-plant roots. Full-grown larvae were found to move horizontally 10–20?cm from their feeding sites and burrow underground. These wandering larvae retained ectomycorrhizal fungal spores in their intestines, which were excreted following relocation to underground pupation sites. Excreted spores retained germination and infection capacities to form ectomycorrhiza on host-plant roots. In the infection experiments, ectomycorrhizal fungal spores applied in the vicinity of underground host-plant roots were more effective in forming ectomycorrhiza than those applied to the ground surface, suggesting that belowground transportation of spores by M. angustifrons larvae could enhance ectomycorrhizal formation. These results suggested that M. angustifrons larvae act as a short-distance spore transporter of ectomycorrhizal fungi.     

Soil modification by different tree species influences the extent of seedling ectomycorrhizal infection

Established vegetation can facilitate the ectomycorrhizal infection of seedlings, but it is not known whether this interaction is limited by the phylogenetic relatedness of trees and seedlings. We use a series of bioassay experiments to test whether soil modification by different ectomycorrhizal tree species causes different levels of seedling infection, whether the extent of seedling infection is a function of the relatedness of tree and seedling, and whether the effect of trees on seedlings is mediated by biotic or abiotic soil factors. We found that soils from under different tree species do vary in their mycorrhizal infectiveness. However, this variation is not related to the genetic relatedness of trees and seedlings but instead, appears to be an attribute of the overstory species, irrespective of seedling species, mediated through a suite of humus- and base-cation-related abiotic effects on soils. Modification of abiotic soil properties by overstory trees should be considered as an important factor in the effect of different overstory trees on the extent of seedling mycorrhizal infection.     

Early emergence increases survival of tree seedlings in Central European temperate forests despite severe late frost

Global warming is expected to result in earlier emergence of tree seedlings that may experience higher damages and mortality due to late frost in spring. We monitored emergence, characteristics, and survival of seedlings across ten tree species in temperate mixed deciduous forests of Central Europe over one and a half year. We tested whether the timing of emergence represents a trade‐off for seedling survival between minimizing frost risk and maximizing the length of the growing period. Almost two‐thirds of the seedlings died during the first growing period. The timing of emergence was decisive for seedling survival. Although seedlings that emerged early faced a severe late frost event, they benefited from a longer growing period resulting in increased overall survival. Larger seedling height and higher number of leaves positively influenced survival. Seedlings growing on moss had higher survival compared to mineral soil, litter, or herbaceous vegetation. Synthesis. Our findings demonstrate the importance of emergence time for survival of tree seedlings, with early‐emerging seedlings more likely surviving the first growing period.