Ground predator activity-density and predation rates are weakly supported by dry-stack cow manure and wheat cover crops in no-till maize
Increasing semi-natural or non-crop vegetation around fields offers some habitat and resources for predators and can increase biological control in fields, but often takes land out of production and fails to support predators in the center of large fields. In-field habitat modifications may be more attractive to farmers and support greater biological control in field interiors. We investigated two in-field habitat manipulations that have benefits for producers and for soil health: fertilizing with dry-stack cow manure and planting a wheat cover crop. We hypothesized that, compared to inorganic fertilizer and fallow plots, both treatments augment habitat and residue in the field and support more small detritivore arthropods that can serve as alternative prey for larger predators. As a result, we expected manure and the cover crop to increase ground active predators. In turn, these predators could provide biological control of pests. Each year in a three-year field experiment, we applied manure and in two years planted a wheat cover crop. We found that both planting a cover crop and applying dry-stack manure increased the plant cover in May of 2017 and 2018. In 2018 this translated to greater soil mite density. However neither manure nor the wheat cover crop increased residue on the soil surface at the end of the experiment. As a result, our treatments had inconsistent effects on predator activity-density, especially for carabids and spiders. We observed strong edge effects from neighboring grass alleys on carabid activity-density. Regardless of treatment, we observed high predation of sentinel prey, perhaps because even without cover crops or organic fertilizer, the stability of no-till maize and increased weeds in fallow treatments generate sufficient cover and residue to support robust predator communities.
|Ground predator activity-density and predation rates are weakly supported by dry-stack cow manure and wheat cover crops in no-till maize
|Data and R Markdown docs
|CC0 1.0 (Public Domain Dedication)
|July 16, 2020
This resource is currently not in any collection.