1 Mechanical digestion is evident, where one can see the breaking down of large food particles into smaller ones after being ground by the teeth. 2  While the chemical changes that take place happen within the body and are not visible.
Using a pre-emergent herbicide around your property could stop these territorial plants from overtaking your home's most valued green space. Pre-emergent herbicide is a type of weed killer that prevents weed seeds from sprouting. Unlike normal herbicide, it is meant to stop weeds from growing in the first place by spraying or spreading a chemical onto the soil so that weeds have difficulty placing down their roots.
Overview. A pre-emergent herbicide is a chemical used to control growth of annual weeds by preventing their seeds from germinating. Apply the herbicide to the soil at least one week prior to weed seed germination to establish and be effective.