The basic idea behind Lauren’s study was that planting a border of partridge pea around organic field corn plots (Fig.1) would increase the numbers of these natural enemies. As a result, there would be fewer pests attacking the corn, a reduction in crop damage, and an increase in crop yield. To do this, Lauren meticulously sampled pest and natural enemy populations throughout the growing season in organic corn plots, as well as in either the partridge pea plants or natural grasses (conventional management practice) surrounding them. Lauren also measured pest egg mortality, corn damage (Fig. 3), and crop yield, as well as estimated the economic potential of employing her methods in a commercial organic farming system.
For her economic analysis, Lauren budgeted for all land dedicated to plots of partridge pea in the Conservation Reserve Program – a program which reimburses farmers for land that they set aside for conservation purposes. This is meant to help offset the loss of profit when that land is not in production. When she included this reimbursement in her calculations Lauren found no significant economic difference between traditional organic corn farming (with grassy borders) and organic farming that incorporated borders of partridge pea as a system of conservation biological control. This suggests that even though this experiment did not show economic benefits, this technique could still be applied without a loss to farmers and may possibly supply other benefits, such as nitrogen fixation with the use of partridge pea, not measured by this study.
About the Authors:
Veronica Johnson is a Master’s student whose research focuses on determining the role of different post-harvest litter management practices in the degradation of Cry proteins in genetically modified Bt corn. She is also looking to determine the effects of winter temperature and precipitation on both tissue decomposition and protein degradation under these various litter management practices.
Peter Coffey is a Master's student whose research focuses on using cover crops to optimize sustainable farming economics. His current projects using lima beans and eggplant as model systems focus on plant nutrition, weed suppression, influences on pest and beneficial insects, and crop yield value. Follow him on twitter at @petercoffey.