The mean strength and direction of estimated direct phenotypic selection (S-b), selection on the focal trait while biomass was included as a covariate, on four traits of Gilia tricolor within year and habitat zone.

Selection coefficients were calculated by separate bootstrapped separate generalized linear mixed models predicting relative fitness from standardized values of each trait. Plot was a random effect in each model; standardized biomass was included as a covariate. Selection coefficients in bold have 95% confidence intervals that do not overlap zero; habitat zones with the same letter are within overlapping confidence intervals (see supporting information). Due to limited sample size, S-b was not estimated for the exterior habitat zone in 2008.