What is the primary characteristic of most herbicides?

The primary characteristic of most herbicides is that they are translocated herbicides. Translocated herbicides are designed to be absorbed by the plant and move throughout its system, targeting specific tissues, including the root system. This allows them to effectively kill the entire plant, rather than just the parts where they are applied.

An example of a translocated herbicide is glyphosate, which moves through the plant's vascular system and disrupts key metabolic processes. This quality makes translocated herbicides particularly effective for controlling perennial weeds, which can often regrow from their root systems if only the leaf surfaces are treated.

Contact herbicides, on the other hand, only affect the parts of the plant they come into direct contact with, which can limit their effectiveness against established or deeply rooted plants. While some herbicides can possess characteristics of both categories, the fact that translocated herbicides can systematically eradicate a plant makes them a more defining characteristic of the herbicide type in question.

In contrast, the idea that herbicides have no specific action type does not represent the reality of how these chemicals are formulated and utilized; they are specifically designed for targeted action against unwanted vegetation.