What is the characteristic of contact herbicides?

Contact herbicides are characterized by their ability to act quickly and are lethal to all plant cells they come in contact with. These herbicides work by causing damage to the plant tissues immediately upon contact, leading to cell death. The mode of action does not rely on translocation within the plant system; instead, their effectiveness derives from direct contact with the foliage or stems of the target plants.

The other options, while they may contain elements related to herbicide properties or usage, do not accurately define contact herbicides. For instance, translocation within the plant is a feature of systemic herbicides, which move within the plant to affect other growing parts. Similarly, while some herbicides might be formulated to minimize their impact on aquatic life, contact herbicides are not inherently safe for all aquatic organisms. Furthermore, the effectiveness of contact herbicides does not typically rely on high temperatures; they can function well in a range of conditions, as long as they are applied correctly to the target plants.