What distinguishes contact pesticides from systemic pesticides?

Contact pesticides and systemic pesticides serve different functions when it comes to pest control, and understanding these differences is crucial for selecting the right pesticide for a specific situation.

Contact pesticides function by killing pests upon direct contact. When these pesticides are sprayed onto the target pests, they quickly impair their nervous system, leading to their death. This means that contact pesticides must be applied directly to the pest to be effective, often requiring careful application to ensure that the target pests are exposed.

On the other hand, systemic pesticides are absorbed by plants and translocated throughout their tissues. This means that when pests consume parts of the plant, they ingest the pesticide, leading to their demise. This mode of action allows systemic pesticides to provide longer-lasting protection since they work from within the plant, making them effective against pests that may feed on the plant over time.

Thus, the distinction lies in how each type of pesticide interacts with the pests: contact pesticides kill on contact, while systemic pesticides are taken up by the plant to control pests that feed on it. Understanding this difference helps pesticide applicators determine the most effective pest management strategy for their specific circumstances.