Date of Graduation


Document Type


Degree Name

Bachelor of Science in Agricultural, Food and Life Sciences

Degree Level



Agricultural Education, Communications and Technology


Johnson, Donald

Committee Member/Reader

Brye, Kristopher

Committee Member/Second Reader

Graham, Donna

Committee Member/Third Reader

Miller, Jefferson


Soybean crops must be harvested during a limited time period using expensive combines and associated equipment. Maximizing combine field efficiency, the ratio of the actual harvesting capacity to theoretical harvesting capacity, is an important objective of machinery managers. Spatial and temporal yield data from a 2012 CaseIH 8120 Axial-Flow combine equipped with a 30-foot MacDon D-65 Draper header and the Case-IH Advanced Farming System (AFS) yield monitoring system were used to examine field efficiency when harvesting soybean in three Arkansas Delta irrigated soybean fields during the 2015 season. Time efficiencies (TE) in the three fields ranged from 72.9 to 85.8% (M = 80.9%, SD = 9.6%); width efficiencies (WE) ranged from 96.7 to 98.8% (M = 97.6%, SD = 1.6%); and overall field efficiencies (FE) ranged from 70.4 to 84.8% (M = 79.0%, SD = 9.7%). Contrary to expectations, neither row length nor unadjusted yield was significantly correlated (p < 0.05) with time efficiency, width efficiency, or field efficiency. Time efficiency explained 90.5% (sr2= 0.905) of the unique variance in field efficiency, while WE explained only 1.6% (sr2= 0.016) of the variance in FE when controlling for the effects of TE. Results indicated use of geo-referenced field and performance data can be a useful tool in evaluating combine performance and efficiency; however, availability of data in a more user-friendly format would facilitate its use for that and possible other purposes.


soybeans, farming, Arkansas Delta