Current understanding of the Poa annua life cycle

Abstract

AbstractPoa annua L. is a common component of turfgrass systems both as a weed and a desirable species. Since first classified by Carl von Linné in 1753, nearly 50 taxa of P. annua have been described, with delineations made on the basis of plant morphology and not life cycle. Yet, peer‐reviewed turfgrass literature has recognized only two of these taxa over the past 50 yr, P. annua L. var. annua and P. annua var. reptans, categorizing var. annua ecotypes as upright growing annuals and var. reptans ecotypes as laterally growing perennials. Herein we provide a comprehensive review of peer‐reviewed literature to highlight that these associations between life cycle and plant morphology are flawed given that morphology is plastic and strongly influenced by environment. We conclude by exploring knowledge gaps regarding P. annua perennation that, if addressed through research, would help turfgrass managers better understand the biology of the ecotypes they aim to eradicate or maintain.