Seed Distribution and Invertebrate Seed Predation in No‐Till and Minimum‐Till Maize Systems

Abstract

Core Ideas Minimum tillage was not detrimental to the granivorous invertebrate community. Seed predation was not weed species specific. Minimum tillage could obscure seeds from invertebrate seed predators. The use of low‐intensity tillage is becoming more widespread throughout the United States, and the effects of these tillage methods on invertebrate seed predator activity and weed seed removal is unknown. We investigated the effects of a minimum tillage system (min‐till) (i.e., vertical coulter + rotary harrow + high residue cultivation) that disturbs the first 2 to 5 cm of soil on invertebrate seed predators and invertebrate seed predation in maize (Zea mays L.) fields in the northeastern United States. Pitfall trapping was conducted and weed seed removal was assessed with seed cards in min‐till and no‐till plots. The depth of seed burial by min‐till implements was examined. Overall granivorous invertebrate activity‐densities were higher in min‐till plots when compared with no‐till, with three ground beetle species (Bembidion quadrimaculatum oppositum Say, Pterostichus melanarius Illiger, Chlaenius tricolor Dejean) and field crickets (Gryllus spp.), having increased activity densities and only one ground beetle species (Harpalus pensylvanicus DeGeer), having a decreased activity‐density. Surface seed predation in min‐till and no‐till was not significantly different. Seed burial was found to be significantly higher in min‐till vs. no‐till. We conclude that min‐till is a promising weed management option for the future, but seed burial may hinder the ecosystem service of weed seed predation and bears further examination.