Some examples of how standard chemical terminology is used are given in Figure 5.4. The chemistry of a compound determines how the herbicide will act in biological and physical systems such as plants, animals, soils, and water. Simple chain compounds of carbon, and hydrogen, substituted with nitrogen, sulfur, and oxygen tend to be degraded readily by microbes. Examples include glyphosate, glufosinate, fosamine, and thiocarbamate herbicides. Examples include the chloracetamide, triazine, sulfonylurea, and dinitroaniline herbicides.
More chlorines mean a longer life.
The substitutions and alterations that can be made to an organic acid such as 2,4-D illustrate the effects that chemical structure can have on important herbicidal and mixing properties. The acid form of 2,4-D is only slightly soluble in water and oil, so it has limited use in commercial formulations. The acid can be reacted with bases to form salts and with alcohols to form esters. Salts and esters behave differently. Common salts of organic herbicides include the sodium, potassium, ammonium, and several amine salts.