Comparison between the draft force requirements and the disturbed area of a single tine, parallel double tines and partially swerved double tines subsoilers

Abstract

A field experiments were conducted to compare the field performance of three subsoiler combinations using the draft force requirement and the disturbed area as comparison parameters. The subsoiler combinations are single tine, parallel arranged double tines and partially swerved double tines. The three subsoiler combinations were tested using four operating depths (30, 40, 50, and 60 cm) with and without wings in silty clay loam soil of moisture content (13.54%). The experiment design was randomized complete block design (4 × 2 × 3) with four replicates. The means of the treatments were compared using RLSD at probability level of 1%.The draft force requirements for S, PSS and PAS increased with operating depth and with wings addition. The mean of the draft force requirement for S, PSS and PAS are 15.30, 22.69 and 30.68 kN respectively. For the single tine of PSS, the draft force requirement is the lowest while for S was medium and for SSP is the highest; these values are 11.35, 15.18 and 15.30 kN respectively. The disturbed area for S, PSS and PAS increased with operating depth and with wings addition. The disturbed area for the three subsoiler combinations was as follows PAS > PSS > S. However, for PAS it was greater than that of PSS by only 3%, whereas, its draft force was greater than that for PSS by 8 kN. The field observations showed that PAS suffered from soil blockade which caused soil billing up in front of the two tines and that resulted in higher draft force requirement while, the contrary occurred with PSS, the soil easily flow between the two tines which reduced its draft force requirement. From the results and the field observations PSS surpassed S and PAS in giving better field performance.