Summary1. Developing restoration strategies that accelerate natural successional processes and are resource-efficient is critical to facilitating tropical forest recovery across millions of hectares of deforested lands in the tropics. 2. We compared tree recruitment after a decade in three restoration treatments (natural regeneration, applied nucleation/island tree planting and plantation) and nearby reference forest in the premontane rain forest zone in southern Costa Rica. The study was replicated at 13 sites with a range of surrounding forest cover, enabling us to evaluate the relative influence of local restoration treatments and landscape forest cover on tree recruitment. 3. Density of small-seeded (<5 mm), animal-dispersed recruits was lower in natural regeneration than in applied nucleation, plantation or reference forest plots. Species richness, species density and density of medium (5-10 mm)-and large (>10 mm)-seeded, animal-dispersed recruits were greatest in reference forest, intermediate in applied nucleation and plantation and lowest in natural regeneration plots. 4. Recruit composition differed substantially between reference forest and all restoration treatments. In general, plantation recruit composition was more similar to reference forests and natural regeneration least similar; however, there was high within-treatment variation. 5. Models suggested weak support for the effect of surrounding forest cover on tropical tree recruit density and composition, as compared to restoration treatment and site conditions (e.g. elevation), in this intermediate forest cover landscape. 6. Synthesis and applications. Applied nucleation appears to be a cost-effective strategy as compared to plantation-style planting to accelerate tropical forest recovery regardless of the amount of forest cover immediately adjacent to the site. However, even with active restoration interventions, forest recovery is a multidecade process that proceeds at highly variable rates.

Questions: Vascular epiphytes constitute a large proportion of tropical forest plant biodiversity, but are among the slowest plants to recolonize secondary forests. We asked whether tree planting for ecological restoration accelerates epiphyte community recovery. Does the spatial configuration of tree planting matter? What landscape contexts are most suitable for epiphyte restoration?Location: Restored pastures in premontane Coto Brus County, Puntarenas, Costa Rica. Methods:We surveyed vascular epiphyte species growing on the lower trunks of 1083 trees in 13 experimental restoration sites. Each site contained three 0.25-ha treatment plots: natural regeneration, trees planted in patches or 'islands' and tree plantations. Sites spanned elevational (1100-1430 m) and deforestation (4-94% forest cover within a 100-m radius around each site) gradients.Results: Vascular epiphytes were twice as diverse in planted restoration plots (islands and plantations) as in natural regeneration; we observed this at the scale of individual host trees and within 0.25-ha treatment plots. Contributing factors included that trees in planted restoration plots were larger, older, more abundant and composed of different species than trees in naturally regenerating plots. Epiphyte species richness increased with surrounding forest cover within 100-150 m of restoration plots. Epiphyte communities were also twice as diverse at higher (1330-1430 m) vs lower (1100-1290 m) elevation sites. Epiphyte groups responded differently to restoration treatments and landscape factors; ferns were responsible for higher species richness in planted restoration plots, whereas angiosperms drove elevation and forest cover effects.Conclusions: Tree planting for ecological restoration enriched epiphyte communities compared to natural regeneration, likely because planted forests contained more, bigger and older trees. Tree island plantings were equally effective compared to larger and more expensive plantations. Restoration sites nearer to existing forests had richer epiphyte recolonization, likely because nearby forests provisioned restoration sites with angiosperm seeds. Collectively, results suggest that restoration practitioners can enrich epiphyte community development by planting trees in areas with higher surrounding forest cover, particularly at higher elevations.

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Aims The American leaf spot, caused by Mycena citricolor, is an important disease of coffee (Coffea arabica), mostly in Central America. Currently, there are limited pathogen control alternatives that are environmentally friendly and economically accessible. The use of fungi isolated from the plant endomycobiota in their native habitats is on the rise because studies show their great potential for biological control. To begin to generate a green alternative to control M. citricolor, the objectives of the present study were to (i) collect, identify, screen (in vitro and in planta), and select endophytic fungi from wild Rubiaceae collected in old-growth forests of Costa Rica; (ii) confirm endophytic colonization in coffee plantlets; (iii) evaluate the effects of the endophytes on plantlet development; and (iv) corroborate the antagonistic ability in planta. Methods and results Through in vitro and in planta antagonism assays, we found that out of the selected isolates (i.e., Daldinia eschscholzii GU11N, Nectria pseudotrichia GUHN1, Purpureocillium aff. lilacinum CT24, Sarocladium aff. kiliense CT25, Trichoderma rifaii CT5, T. aff. crassum G1C, T. aff. atroviride G7T, T. aff. strigosellum GU12, and Xylaria multiplex GU14T), Trichoderma spp. produced the highest growth inhibition percentages in vitro. Trichoderma isolates CT5 and G1C were then tested in planta using Coffea arabica cv. caturra plantlets. Endophytic colonization was verified, followed by in planta growth promotion and antagonism assays. Conclusions Results show that Trichoderma isolates CT5 and G1C have potential for plant growth promotion and antagonism against Mycena citricolor, reducing incidence and severity, and preventing plant mortality.

Restoration treatments can impact the growth and development of tree seedlings; however, it is often difficult to discern whether responses are driven by changes in microclimate, biotic interactions, or soil properties. To isolate for the latter, we quantified the growth response of four species [Ocotea puberula (Lauraceae); Otoba novogranatensis (Myristicaceae); Pseudolmedia mollis (Moraceae); Senna papillosa (Fabaceae)] grown under similar shade-house conditions in soils collected from 6-7 year old active (four species plantation) and passive restoration plots (natural recovery), and nearby reference forest sites in Costa Rica. We also evaluated the role of parent tree by collecting individuals from five mother trees. We measured height, above-and belowground biomass, and determined root: shoot ratios (RSR). Species differed markedly in their responses. Ocotea, and to a lesser extent Pseudolmedia, were largely driven by parent tree. In contrast, Senna showed a strong soil response for all variables with more growth in active than passive restoration soils; reference forest seedlings were typically intermediate. An interaction suggested that some genotypes are more responsive to different soil properties than others. Otoba had higher soil-driven RSR in both restoration treatments. Surprisingly most soil nutrients, including %N, were similar or significantly lower in active restoration soils, suggesting that seedlings are responding to differences in soil microbial communities or more labile nutrients (e.g., NH4+ and NO3−). Active restoration appears to facilitate the growth of other species by improving certain soil properties. Additionally, genotypes are an important driver of seedling vigor and some species may be more responsive to subtle differences in soil properties than others.

1. In degraded tropical landscapes, lack of seed dispersal can strongly limit recovery, and restoration interventions can overcome this barrier by attracting dispersers.However, seed dispersal patterns are typically studied over short time periods, thus the influences of temporal and spatial variability on seed arrival cannot be teased apart.2. The choice of management approach can have important implications for restoration-mediated community reassembly. Accordingly, we used a 3.5-year record of seed deposition in pre-montane tropical wet forest in southern Costa Rica to examine how seed arrival differed between passive (natural regeneration) and active (applied nucleation, plantation) restoration after a decade of recovery, compared to remnant forest. We investigated: (a) how restoration treatments affected seed deposition rates and community composition; (b) how within-plot heterogeneity of animal-dispersed seed deposition varied by intervention; and (c) how interannual variation influenced animal-dispersed seed arrival across treatments.3. Overall seed rain composition and diversity in restoration treatments was converging towards, but still differed substantially from, remnant forest (89.7%, 86.6% and 76.3% Shannon diversity recovered in applied nucleation, plantation and natural regeneration respectively). 4. Within-plot animal-dispersed seed heterogeneity was similar in applied nucleation and remnant forest, 27.0% more heterogeneous in applied nucleation than

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