Performance Evaluation of a Back-Mounted Weed Control Machine with Drip Irrigation for Fruit Trees

This study aimed to evaluate the factors that affect the performance grade of a back-mounted weed control machine used with drip irrigation for smallholder fruit tree growers. Evaluating experiments were executed on guava and lemon trees. The studied factors were four rotational blade speeds (220, 330, 450, and 600 rpm), three interchangeable weeding attachments brush cutter rotary cultivator, cutter weeder, and vertical rotavator), three weed densities (Numbers/m²), and two drip-irrigation systems (surface and subsurface). The results showed that the rotary cultivator operating at 450 rpm achieved the maximum weeding efficiency of 99% in surface irrigation, followed by the cutter weeder (97%) and the vertical rotavator (95%), compared to manual weeding, which achieved 100% (control treatment). At subsurface irrigation consistently resulted in lower efficiency, about 36 basins/h (113 m²), compared to surface irrigation, which reached 40 basins/h (120 m²/h). In contrast, hand weeding recorded 25 basins/h (79 m²/h). However, increasing the rotational speed from 220 to 600 rpm causes an increase in the percentage of damaged pipes from 0 to 1.8% at surface irrigation. An economic assessment indicated that the vertical rotavator at surface irrigation was the most cost-effective option, with an operating cost of (1.9 EGP/basin), which was slightly higher than that at subsurface irrigation. In comparison, hand weeding recorded an operating cost of (2.6 EGP/basin). It can be concluded that operating the rotary cultivator at 450 rpm at surface irrigation is recommended for optimal weeding efficiency and economic feasibility, with minimal damage at irrigation system pipes.