Table S4.

Correlation matrix between variables used to predict peak flowering times

Predictor variable	Species diversity	Soil moisture	Soil surface temperature	Available soil N
Species diversity	1	−0.24*	−0.30**	−0.18†
Soil moisture		1	0.016	0.17
Soil surface temperature			1	−0.068
Available soil N				1

Species diversity was deliberately manipulated; soil moisture (%), soil surface temperature (°C), and available soil N (micrograms of N per gram of resin per day) were measured for each plot. Soil moisture, soil surface temperature, and available soil N were log-transformed for this and all other analyses. The significance of the correlations is indicated: **P < 0.01; *P < 0.05; ^†P < 0.1 (marginally significant).