Enemy exclusion effects on biodiversity-productivity relationship in subtropical forest experiment

This data set is described in full detail in Huang et al. (2022) Journal of Ecology XXX.

In brief, we used a large tree biodiversity experiment (BEF-China), established in 2009-2010, to test whether the application of fungicide or insecticide changes observed tree species richness effects on tree growth. We used a subset of plots in which tree species numbers ranged from 1 to 8. To these plots, a factorial split-plot treatment was added in April 2014. The new treatments (I: insecticide; F: fungicide; C: untreated control) were applied to subplots located along one side of the main plots. Each subplot contained 4 × 4 = 16
trees. We further used the central 4 × 4 trees of the main plot for additional measurements (central control subplot).

Insecticide and fungicide solutions (4 L per subplot) were sprayed over tree crowns every 4 weeks, but only on days with no or very little wind. During the rainy season, application
intervals were halved to 2 weeks to compensate for more rapid leaching. The insecticide solution contained 10 mL dimethoate (an organophosphate) and 10 mL deltamethrin (a
pyrethroid). The fungicide solution contained 8 g of mancozeb (a dithiocarbamate) and 25 mL of myclobutanil (a triazole). Control subplots were sprayed with 4 L of water.