Higher apical meristem in tall fescue as adaptation strategy to recurring short-term inundation

Soil inundation frequency and intensity in the central United States are predicted to increase because of climate change. Soil inundation is expected to negatively affect plant growth and persistency. Our objective was to measure tiller and apical meristem height, leaf area index (LAI), and leaf-to-stem ratio effects on tall fescue (Schedonorus arundinaceus (Schreb.)) under different levels of soil inundation intensity. The study was conducted on a commercial farm in northwestern Ohio, from spring to fall 2021. Three different levels of inundation were observed and assigned as treatments: no inundation, low inundation (LI), and high inundation (HI). LI and HI were defined by the duration on which the soil was inundated after heavy rain events: 1–2 and 3–5 days after rain, respectively. Meristem and tiller height were higher during spring (p < 0.001), and lower in late summer across treatments (p < 0.001). The higher LAI and leaf-to-stem ratio occurred in spring, probably due to higher leaf mass (p < 0.001). As seasons progressed, plant and meristem height, LAI, and leaf mass decreased (p < 0.001). Despite not being considered an inundation-tolerant species, tall fescue showed morphological adaptation to the inundation levels of our study, suggesting that this species can be used to manage fields prone to short-term inundation.