Does the applied gauge-wheel loads have influence on seeding depth and soil structure?

Authors: OLIVIERA, LUAN - Auburn University; ORTIZ, BRENDA - Auburn University; SILVA, ROUVERSON - Sao Paulo State University (UNESP); Way, Thomas - Tom; OLIVIERA, MAILSON - Auburn University; PATE, GREGORY - Alabama Agriculture Experiment Station

Submitted to: Proceedings of the American Society of Agricultural and Biological Engineers International (ASABE)
Publication Type: Proceedings
Publication Acceptance Date: 7/16/2021
Publication Date: 7/16/2021
Citation: Oliviera, L., Ortiz, B., Silva, R., Way, T.R., Oliviera, M., Pate, G. 2021. Does the applied gauge-wheel loads have influence on seeding depth and soil structure?. Proceedings of the American Society of Agricultural and Biological Engineers International (ASABE). 2101211. https://doi.org/10.13031/aim.202101211.
DOI: https://doi.org/10.13031/aim.202101211

Interpretive Summary: Many types of agricultural crops are planted using row crop planters. Attaining good contact of the crop seed with soil is important in getting moisture from the soil to the seed, to promote seed germination, emergence of the plant from the soil, and growth of the plant. Row crop planters can be equipped with computer-controlled hydraulic downforce systems for controlling the vertical force applied by the planter to the soil. We used a planter equipped with a hydraulic downforce system, planting cotton in a no-tillage loamy sand soil. Seeding depth increased as the downward force increased. Gauge wheels on the planter support a substantial portion of the planter weight. The hydraulic downforce system has an active mode which adjusts the gauge wheel vertical force using lift or downforce according to soil variability, and a fixed mode in which the system uses downforce alone. Greater uniformity of seeding depth is desirable, and we found that seeding depth was more uniform for the active mode than for the fixed mode.

Technical Abstract: The inadequate use of farming machinery could have negative impacts on soil structure and crop growth. During planting, a row-unit downforce system is used to reach and maintain a target seeding depth by applying downward forces to the planter gauge-wheels. These forces are transferred to the soil and can increase the soil bulk density resulting in soil compaction. This study aimed to evaluate if gauge-wheel load, created by a hydraulic downforce system, influences seeding depth, soil cone index, and bulk density using downforce in active (dynamic) and fixed (static) operational modes during cotton sowing. The experiment was conducted on a no-tillage loamy sand soil. A six row John Deere MaxEmerge Plus planter with a 91 cm row spacing was equipped with a hydraulic downforce system. For the static operational mode of the downforce mechanism, five load levels were tested: NDF (Row-unit weight), Low - 535 N, Medium - 667 N, High - 890 N, and Very High - 1112 N. Four loads were evaluated using the dynamic mode: same low and medium loads as in manual mode, and also 756 N and 867 N, which were considered as High and Very High, respectively. When the static mode was used, the applied load exceeded the target load, especially when 890 and 1112 N were applied. Overall, the applied final load was close to the target and exhibited less variability when the dynamic mode was used, compared to the static mode. Seeding depth increased as the downward force increased. The dynamic mode provided less seeding depth variability than the static mode. When the dynamic mode was used, an increasing load caused soil cone index to increase, but did not affect soil bulk density.