What type of ester is known as a high-volatile ester?

The correct choice identifies butyl-ester as a high-volatile ester, which is important in herbicide application contexts. High-volatile esters are characterized by their increased tendency to vaporize at common environmental temperatures, which can affect both their efficacy and the potential for off-target movement. This is particularly relevant in agriculture since high volatility can lead to herbicide drift, impacting neighboring crops and sensitive areas.

Butyl-esters are used in various herbicide formulations due to their balance of performance and volatility. Their higher volatility means they can evaporate more quickly, which can enhance penetration through plant surfaces for certain applications but also necessitates careful application timing and methods to minimize drift.

Other esters listed, like ethyl, methyl, and propyl, generally exhibit lower volatility compared to butyl-esters. Understanding the volatility of these compounds is essential for safe and effective herbicide use, as selecting the right type of ester can significantly influence both application success and environmental safety.