Shortgrass steppe and northern mixedgrass prairie plant species traits

Despite progress in trait-based ecology, there is limited understanding of the plant traits that structure semiarid grasslands. In particular, it remains unclear how traits that enable plants to cope with water limitation are related to traits that influence other key functions such as herbivore defense and growth. The hypothesis that drought and herbivory exert convergent selection pressures is supported for morphological traits, but largely untested for struct­ural, physiological, and phenological traits. Drought and economic traits can also covary, but where and to what degree remains uncertain.

Here we address these uncertainties in semiarid shortgrass steppe and mixedgrass prairie, the largest remaining grasslands in North America. Using a broad selection of traits for 37 of the most common plant species in each ecosystem, we ask whether traits that confer drought tolerance, avoidance and escape covary with herbivore resistance traits and economic traits.

Results reveal that ...