Competition and Niche Requirements ofCoreopsis tinctoria: A Widespread but Local High Density Annual Asteraceae

Abstract

Coreopsis tinctoria (coreopsis, calliopsis, plains coreopsis, or golden wave) is an annual herbaceous Asteraceae with a broad geographic distribution mostly in the central and western United States. It co-occurs with Bouteloua curtipendula (sideoats grama) or other native C 4 grasses. When grown together, C. tinctoria response variables decreased significantly in the presence of B. curtipendula aboveground, belowground, and total dry mass. The response variables included mean plant height, number of flower buds per plant, flowers per plant, as well as aboveground, belowground, and total dry mass. The presence of B. curtipendula belowground dry mass caused the greatest suppression of C. tinctoria belowground dry mass. When B. curtipendula tops were clipped to reduce grass aboveground dry mass (simulated herbivory), the percent survival of C. tinctoria plants increased from one percent in the no-clipping treatment to 18% in the neighbor removal treatment (100% clipped). Coreopsis tinctoria does not appear to be a good competitor in the presence of B. curtipendula and seems to be restricted to gaps or patches in disturbed grasslands where competition from perennial grass neighbors is reduced.

Effects of the soil microbiome on the demography of two annual prairie plants

“…This scale ranges from 0 to 10; these low values are consistent with the annual plants' ability to establish themselves in recently disturbed areas; later successional perennial plants typically have higher scores (Herman et al., 1997). Consistent with these coefficients, Coreopsis was one of the first species to colonize areas near forb‐sown prairie restoration plots (Jaksetic, Foster, Bever, Schwarting, & Alexander, 2018) and it is a poor competitor with perennial grasses (Elliot & Van Auken, 2014). Similarly, Chamaecrista is found primarily in disturbed areas, including recently burned or animal‐disturbed parts of prairies and roadside habitat (Galloway & Fenster, 2000).…”