What is typically a characteristic of systematic herbicides?

Systematic herbicides are designed to be absorbed by the plant and then translocate throughout its tissues. This property allows them to effectively target and eliminate unwanted weeds and plants, even those that are not directly sprayed. When these herbicides are absorbed through the leaves or roots, they move systematically within the plant, reaching areas that are difficult to treat and affecting the plant's overall health.

This translocation is crucial for the efficacy of systematic herbicides because it ensures that the herbicide reaches all parts of the plant, including the roots and other vital systems. As a result, these herbicides can treat a broad spectrum of plants and are particularly useful in managing perennial weeds, which may have extensive root systems.

In contrast, the other statements do not accurately represent the characteristics of systematic herbicides. For instance, while some herbicides may be less effective in dry conditions, systematic herbicides do not inherently depend on dry conditions to function. Additionally, they are not immediately absorbed by the soil; rather, they are meant to enter the plant itself. Lastly, effective doses can vary, and systemic herbicides do not necessarily require high doses to be effective as they work by being absorbed and translocated throughout the plant.