Herb layer vegetation surveys were conducted in August–September 2024 during the field campaign of the third TreeDi cohort. Sampling was carried out in experimental units referred to as TSQ (Tree Species Quartets). Within each TSQ, herb layer vegetation was recorded to quantify cover, species composition and diversity.

The data were collected within the BEF-China tree diversity experiment in subtropical China (site B). Sampling was conducted in Tree Species Quartets (TSQs), experimental units defined by combinations of four tree species within the plots. Herb layer vegetation surveys were carried out during the field campaign of the third TreeDi generation (August 2024). Within each TSQ, vegetation of the herb layer was recorded and environmental variables as well as vegetation structure were assessed. TSQs differed in shrub treatment, with either Distylium buxifolium, Viburnum setigerum, or no shrub present (control).

BEF-China, site B, selected superplots of the Tree species Quartets (TSQs).

Field surveys were conducted under generally favourable weather conditions with little precipitation during the sampling period.

The dataset was used to examine how tree layer characteristics, shrub presence and structure, and environmental variables influence herb layer vegetation in the BEF-China experiment, with a focus on herb layer diversity and vegetation cover.