Early- and late-flowering forbs and recruitment limitation

We conducted an experiment to test whether three early- and three late-flowering forb species are seed or recruitment limited, if mowing can incluence this limitation, and if forb additions will impact overal plant diversity in ongoing restorations.  A split-plot design was initiated with mowing or no mowing in main plots, and forb additions (transplants or seeds, single species or mixtures) in suplots at three sites.  Target forb biomass, survivorship and percent cover were sampled over three years (2019-2021).  target forb total biomass (all individuals combined per plot) was much higher when transplants were added than when seeds were added.  Plant diversity measures were estimated within subplots to determine if forb additions impacted diversity.  Plant diversity was higher when forbs were transplanted, than when they were seeded, and diversity increased linearly with the number of forb species added.  Mowed and unmowed plots had similar diversity and forb abundances.  We recommend transplanting a rich mix of early and late flowering forbs to increase their biomass and ensure flowering throughout the growing season in prairie restorations.