What does the term "systemic pesticide" refer to?

The term "systemic pesticide" specifically refers to a type of pesticide that is absorbed by plants and translocated throughout their tissues. This means that when a plant takes up the pesticide, it spreads through the internal vascular system, allowing the chemical to affect pests that feed on the plant, even if those pests do not come into direct contact with the pesticide itself. This mode of action is particularly effective for managing pests that are difficult to control through contact pesticides because it works from within the plant.

In contrast, the other options describe different types of pesticide actions or characteristics that do not align with the definition of systemic pesticides. The first option refers to contact pesticides, which act solely on the pests that come into direct contact with them. The third option discusses soil health, which relates more to agricultural practices rather than a specific strategy for pest management. Lastly, the mention of evaporation pertains to the volatility of certain pesticides, which does not relate to how systemic pesticides operate in managing pests.