Active restoration increases tree species richness and recruitment of large-seeded taxa after 16-18 years

Tropical forest restoration presents a potential lifeline to mitigate climate change and biodiversity crises in the Anthropocene. Yet, the extent to which human interventions, such as tree planting, accelerate the recovery of mature functioning ecosystems or redirect successional trajectories towards novel states remains uncertain due to a lack of long-term experiments. In 2004-2006, we established three 0.25-ha plots at ten sites in southern Costa Rica to test three forest restoration approaches: natural regeneration (no planting), applied nucleation (planting in patches), and plantation (full planting). In a comprehensive survey after 16-18 years of recovery, we censused >80,000 seedlings, saplings, and trees across 26 restoration plots (9 natural regeneration, 9 applied nucleation, 8 plantation) and six adjacent reference forests to evaluate treatment effects on recruitment patterns and community composition. Both applied nucleation and plantation treatments resulted in significan..., , , # Active restoration increases tree species richness and recruitment of large-seeded taxa after 16-18 years

[https://doi.org/10.5061/dryad.s7h44j1gc](https://doi.org/10.5061/dryad.s7h44j1gc)

## Description of the data and file structure

STUDY AREA AND BACKGROUND ON EXPERIMENT
Data collection occurred Jun-Jul 2022 in Coto Brus county of southern Costa Rica near Las Cruces Biological Station. The data represent full censuses of 26 plots from 10 restoration sites and six plots sampled from mature reference forests in adjacent areas at six of these locations. Restored areas were designed to have an area of 0.25 ha with either 48x48 m or 42x54 m dimensions with a ≥5-m buffer. Restoration experiments initiated in 2004-2006, when each plot received one of three randomized treatments: natural regeneration n = 9 plots, applied nucleation n = 9, or plantation n = 8. Some of the sites were missing one or two treatments due to their being destroyed or heavily damaged by this point in the study,..., , **Changes after Sep 25, 2024:**

Changes as of 12 Dec 2025 have been made to document the application of this published dataset for a new manuscript that focuses on small-scale spatial analyses of within restored and reference plots accepted for publication in the Journal of Applied Vegetation Science.

Changes are summarized as follows:\
-addition of the code supporting the 2025 analyses

-addition of four files: (updated taxonomic nomenclature (i.e., species codes) and corresponding attributes relevant to these analyses for the tree species list; \
and reference Cartesian grids that code the position of each 3x3 sub-quadrat from the plot center. These files are given in 3 variations, which reflect the template plot structure used in the experiment:\
(1) Standard (48 x 48 m)\
(2) Long (42 x 54 m)\
(3) Reference (21 x 21 m)

Survey grid layout terminology differs slightly between field use and the most recent manuscript. Translations from the supplementary figure of the grid are as foll...