What ingredient is used in a flushing solution to irritate pests?

The use of lemon-scented dishwashing detergent in a flushing solution makes sense due to its surfactant properties and the fact that it can create a sense of irritation for pests like aphids or spider mites. The detergent functions by breaking down the surface tension of pests, making them more susceptible to being dislodged from plants. Additionally, the citrus scent may also create discomfort or confusion for certain pests, urging them to leave the treated area.

While other ingredients like white vinegar and vegetable oil can also interact with pests, they typically serve different purposes. Vinegar could deter pests due to its acidity, but it does not have the same aggressive dislodging effect as a detergent. Vegetable oil might suffocate pests or serve as a barrier, but it lacks the irritative quality that promotes flushing. Fabric softener is primarily designed to reduce static and soften fabrics, not to target pests effectively, indicating that it doesn't serve the same purpose in pest management as a detergent does.