Data from: Mycorrhizal identity and light shape tree seedling biomass responses in plant–soil feedbacks
Data files
Feb 04, 2026 version files 96.67 KB
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Field_Data.csv
28.57 KB
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GH_Data.csv
62.72 KB
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README.md
5.38 KB
Abstract
Plant–soil feedbacks (PSFs) are key drivers of forest composition and diversity, yet their direction and magnitude may depend on the mycorrhizal identity of interacting species, environmental conditions, and experimental context. We conducted complementary greenhouse and field experiments using Acer rubrum L., Acer saccharum Marsh., Prunus serotina Ehrh. (all arbuscular mycorrhizal [AM] species), and Quercus alba L., and Quercus rubra L. (all ectomycorrhizal [EM] species) to test how biomass-based PSFs vary with mycorrhizal matching between seedlings and adult trees, light availability, and soil microbial communities. Seedlings were grown in soil conditioned by conspecifics, conmycorrhizal heterospecifics, or heteromycorrhizal heterospecifics under controlled and natural light regimes. Consistent with expectations, AM species consistently exhibited negative PSFs under low light, and EM species tended to show more positive PSFs, but this pattern was contingent on light and greenhouse versus field setting. For AM species, negative PSFs occurred primarily under low light and were neutralized or reversed under higher light. EM species showed generally more positive PSFs across light levels and settings, although species-specific differences emerged. PSFs were driven largely by conspecific soil conditioning, with limited influence from the mycorrhizal identity of heterospecific neighbors. Results from greenhouse versus field settings diverged, with field PSFs sometimes attenuated or reversed, particularly for Q. alba. These findings highlight that biomass-based PSFs are not fixed species traits but context-dependent outcomes influenced by mycorrhizal type, light availability, and environmental setting. Incorporating these factors is essential for predicting how PSFs influence seedling recruitment, forest dynamics, and biodiversity.
Dataset DOI: 10.5061/dryad.rfj6q57qj
Description of the data and file structure
Experimental Design and Data Collection
We conducted complementary greenhouse and field transplant experiments to test how plant–soil feedbacks (PSFs) vary with mycorrhizal identity, soil source, sterilization of conspecific soils, and light availability. Five temperate tree species differing in mycorrhizal association (Acer rubrum, Acer saccharum, Prunus serotina, Quercus alba, Quercus rubra) were used in the greenhouse experiment. Two EM species (Q. alba, Q. rubra) were used in the field experiment. Soils were collected from mapped adult trees in a mixed hardwood forest and used either live (non-sterile) or sterilized to isolate biotic versus abiotic soil components.
Greenhouse Experiment
The greenhouse experiment was conducted at Michigan State University’s Tree Research Center (East Lansing, Michigan, USA; 42.7°N, 84.5°W). Three light environments (~2%, ~15%, and ~30% full sunlight) were created using shade cloth and reflective material. Seedlings were grown in soil sourced from conspecific and heterospecific adults spanning both AMF- and EMF-associated species. A subset of conspecific soils was gamma-sterilized to remove soil biota without substantially altering soil chemistry or physical structure.
Pots containing a 1:1 mix of field soil and potting substrate were arranged across nine greenhouse benches, with three benches per light level. Each species × soil source × light combination had 30 replicates, for a total of 3,150 seedlings. Seedlings grew for 12 weeks, after which whole-plant dry biomass (mg) was recorded.
Field Transplant Experiment
The field experiment was conducted at Alma College’s Ecological Field Station (Vestaburg, Michigan, USA; 43.4°N, 84.9°W) using Q. alba and Q. rubra seedlings. Intact soil cores (46 cm depth) were collected under mapped adult trees in 2016 and 2017 and transplanted into 18 field plots arranged across a canopy light gradient. Plots were subdivided into five subplots (A–E). Seedlings were planted into cores and grown for two full growing seasons.
Canopy light was quantified for each subplot using hemispherical photographs to derive Indirect Site Factor (ISF). ISF values were grouped into categorical low, medium, and high light classes. Soils included conspecific and heterospecific live cores, and sterilized conspecific cores. Two EM species (Q. alba, Q. rubra) were grown across all soil types; seedling whole-plant dry biomass (mg) was recorded at the end of the experiment.
Files and variables
File: GH_Data.csv
Description: Greenhouse Experiment
Variables
- Number: Unique seedling identifier
- Species: Seedling species
- ACRA = Acer rubrum
- ACSA = Acer saccharum
- PRSE = Prunus serotina
- QUAL = Quercus alba
- QURU = Quercus rubra
- Soil: Soil source (adult species)
- ACRA = Acer rubrum
- ACSA = Acer saccharum
- PRSE = Prunus serotina
- POGR = Populus grandidentata
- QUAL = Quercus alba
- QURU = Quercus rubra
- CON-ST = sterile conspecific
- Light: Light treatment
- Low (~2% full sunlight)
- Med (~15% full sunlight)
- High (~30% full sunlight)
- SpMyco: Seedling mycorrhizal type
- AMF or EMF
- Conspecific: Seedling–soil identity
- CON (conspecific live)
- CON-ST (conspecific sterile)
- HET (heterospecific live)
- SoilMyco: Mycorrhizal type of soil source adult
- AMF, EMF, or Sterile
- Adult: Unique identifier for adult tree soil source
- Bench: Greenhouse bench
- Biomass: Final whole-plant dry mass (mg)
File: Field_Data.csv
Description: Field transplant experiment
Variables
- No: Unique seedling identifier
- Plot: Field plot (1–18)
- Subplot: Subplot (A–E)
- Species: Seedling species
- QUAL = Quercus alba
- QURU = Quercus rubra
- Light_ISF: Numeric Indirect Site Factor value from hemispherical photography
- Light: Light class (Low, Med, High) based on ISF
- Core: Year soil core was collected (2016 or 2017)
- Soil: Soil source (adult species)
- ACRA = Acer rubrum
- ACSA = Acer saccharum
- PRSE = Prunus serotina
- POGR = Populus grandidentata
- QUAL = Quercus alba
- QURU = Quercus rubra
- CON-ST = sterile conspecific
- Adult: Unique identifier for soil-source adult tree
- Conspecific: Seedling–soil identity
- CON (conspecific live)
- CON-ST (conspecific sterile)
- HET (heterospecific live)
- Myco: Seedling mycorrhizal type
- EMF for all entries
- SoilMyco: Mycorrhizal type of soil source adult
- EMF, AMF, or Sterile
Biomass: Final whole-plant dry mass (mg)
Code/software
All analyses were conducted in R (v.3.5.1). Linear mixed-effects models were fit using lme4; significance and pairwise tests were obtained using car and emmeans. Biomass-based PSFs were quantified using log-response ratios with nonparametric bootstrapping.
Access information
For questions related to data, methodology, or availability:
Dr. Sarah McCarthy-Neumann
Email: sneumann@tnstate.edu
