The mean strength and direction of estimated direct phenotypic selection (<i>S_-b</i>), selection on the focal trait while biomass was included as a covariate, on four traits of <i>Gilia tricolor</i> 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.