The Impact of Tillage and Weed Control Methods on Physical Properties of Sandy Clay Loam Forest Ochrosol in Cassava Cultivation

The field study was carried out on a sandy clay loam forest ochrosol at Hodzo, near Ho in Ghana, from July 2017 to May 2018. The objective was to determine how tillage and weed control techniques affect the physical properties of the soil. The split-plot design was used in the study, with tillage serving as the main factor and weed control serving as the subplot factor. The tillage treatments were no tillage (NT), minimum tillage (MT), and ploughing followed by harrowing and ridging (PHR) and deep tillage followed by Ploughing, harrowing, and ridging (DPHR). On the other hand, the weed control treatments comprised hoe weeding, machete weeding, and no weeding. It was realised during the study that, in the upper layer (0-15 cm), the PHR treatment produced lower soil penetration resistance (38.57 kPa), high dry bulk density (1.019 Mgm(-3)), and slightly lower soil moisture content (5.0%) in comparison with the other tillage treatments at three months after planting (3 MAP). The results on initial and basic infiltration rates portrayed a trend where the more intensive the tillage regime (hence, soil disturbance), the lower the initial and basic infiltration rates, and vice versa. Moreover, tillage had a higher impact on the physical characteristics of the soil than weed control methods. Nonetheless, tillage with machete weeding resulted in lower soil dry bulk density and higher moisture content, while tillage with hoe weeding reduced penetration resistance and increased infiltration rates. Given similar weather and soil conditions, the study recommends that farms and farmers in the Ho Municipality and the Volta Region adopt conservative tillage methods such as heaping with machete or hoe weeding and use the savings to expand their farm sizes. Therefore, the adoption of conservation tillage practices is more crucial than ever in order to ensure sustainable food production with minimal impact on the soil and environment.