herbicides application

Angel

Why moisture is necessary when we apply pre-emergence herbicides?

Ephraim

Pre emergence herbicides are applied over soil surface after sowing of crop and before emergence of weed. Proper moisture content should be there in soil to make sure of better breakdown and sometime hydrolysis of herbicidal molecules into simpler compounds, which is the ultimate lethal product to kill weed propagules present in the soil system or about to be emerged from soil.