Sustainable Integrated Pest Management Strategies for Theba pisana in Northern Jordan

This study tested a pest management approach that uses farming, manual, natural, and chemical methods together to control Theba pisana, an invasive snail harming citrus, grape, and vegetable crops in northern Jordan. Field tests in Irbid and Ajloun from March to May 2024 showed that the combined pest management plan cut the number of snails by 86.3% (down to 55 ± 5 per square meter) and reduced crop damage by 90.0% (down to 8.5 ± 1.0%) after 8 weeks. This was much better than using just one method, which only reduced snail numbers by 46.8–67.9% and damage by 45.5–75.4%, compared to fields with no pest control (200 ± 15 snails per m², 52.5 ± 3.1% damage). The combined plan kept snail numbers below the economic limit of 50 per square meter and increased yields of citrus, grapes, and vegetables by about 28%. Weather and environment were important: soil moisture and plant cover increased snail numbers, while snail poison in the soil lowered them. The iron-phosphate used stayed below safe levels (0.2 mg/kg), so it was not harmful to the environment. The pest management approach cost $170 per hectare, but brought in a net return of $840 per hectare and a benefit–cost ratio of 5.9, which was better than just chemicals alone ($640/ha, ratio 4.0). These results show the plan is safe, profitable, and could work well for other places facing similar snail problems.