Behavior of Herbicides in Soil

I. The Effect of Soil Type on the Activity of Herbicides

Abstract

A laboratory test was conducted to determine the effect of soil type on the activity of fifteen herbicides. With cucumber and wheat seedlings, bioassay for fourteen days following herbicide application was made in quartz sand and four soils: Shiroishi polder soil containing montmorillonite clay, Tamana red-yellow soil with kaolinite clay, Choyo volcanic ash soil with allophane clay and 13.1% organic matter, and Kodonbaru volcanic ash soil with allophane clay and 32.1% organic matter.
While there were exhibited slight interactions between herbicides and soils, it was generally shown that Choyo and Kodonbaru volcanic ash soils similarly inactivated herbicides most strongly of the four soils, presumably due to soil colloid adsorption, being followed in order by Shiroishi polder soil and Tamana red-yellow soil. Noticeable herbicidal behavior was found with 2, 4-D, dichlobenil, CIPC, and MCPCA ([4-chloro-o-tolyl) oxy] aceto-o-chloranilide) whose inactivation was little or not in Tamana red-yellow soil and Shiroishi polder soil of crystalline clay minerals, whereas great in both volcanic ash soils.