Published online by Cambridge University Press: 11 June 2019
Interseeding provides flexibility in cover crop establishment, but most cover crop species are not well-adapted to the duration of low-intensity light beneath the cash crop canopy. Field pennycress (Thlaspi arvense L.) has physiological seed dormancy traits and its emergence pattern may be better synchronized with cash crop senescence. The objective of this study was to demonstrate proof-of-concept for using pennycress as an interseeded cover crop. A 2-year field experiment was conducted where cereal rye (Secale cereale L.), mustard (Guillenia flavescens L.) or pennycress were interseeded into edamame [Glycine max (L.) Merr.] 1 month after planting. Rye and mustard emerged within 6 days, whereas pennycress emergence was delayed up to 56 days after interseeding. Pennycress provided 37–57% soil cover in fall and produced 0.4–2.5 Mg ha−1 biomass the following spring. Preliminary results demonstrate the utility of pennycress as an interseeded cover crop and the potential value of seed dormancy traits in interseeding systems.