What effect does high surface tension typically have on liquid herbicides?

High surface tension in liquid herbicides generally leads to a decrease in effectiveness. This is because high surface tension causes the herbicide droplets to bead up and resist spreading across the leaf surface of the target weeds. When herbicides do not adequately adhere to or cover the foliage, their chances of being absorbed by the plant are diminished, reducing their potential efficacy in knocking down or controlling the weeds.

The reason why improving coverage is important is that herbicides need to cover a larger area of the plant surface to be effective. When surface tension is high, it works against this principle by causing droplet formation rather than allowing for an even distribution over the leaf. This reduced coverage means that the active ingredient may not sufficiently reach the plant tissues where it can act to disrupt growth processes, ultimately limiting the effectiveness of the herbicide.

In contrast, characteristics like deeper penetration or improved solubility are more closely associated with formulations designed to reduce surface tension or with the use of adjuvants that can modify how herbicides interact with plant surfaces. Thus, the correct understanding is that high surface tension tends to compromise how well the herbicide works on the intended targets.