Results of simple linear regressions of bioassay seedling shoot mass (dependent) against ECMF factors (independent) for different groupings of soil samples.

Forest and moraine soils are not included.

Statistically significant p values are in bold (α = 0.05).

Data on seedling mass and ECM colonization were log and arcsine transformed, respectively.

Number of soil samples included in each grouping.

Slopes are included for significant regressions only.