What is the difference between systemic and contact pesticides?

The distinction between systemic and contact pesticides is crucial for effective pest management. Systemic pesticides work by being absorbed into the plant's tissues, allowing them to affect pests that consume the plant or feed on its sap. This mode of action means that the pesticide circulates throughout the plant, providing protection not only to the parts that are treated but also to areas that may not be directly sprayed. This absorption provides a method of control against pests that typically hide within the plant, such as certain sap-sucking insects.

In contrast, contact pesticides function by killing pests on direct exposure to the chemical. These pesticides do not penetrate the plant and are typically effective only when they come into direct contact with the targeted insects. This method can be effective for certain pests that are easily accessible but may miss pests that hide within or beneath the plant surfaces.

Understanding the differences between these two types of pesticides allows pest control operators to choose the appropriate method based on the specific pest problem and the characteristics of the plants involved in the treatment.