Root mealy bugs look just like normal mealy bugs and produce the same white cottony substance, but feed exclusively on the roots, where they can sometimes remain undetected until repotting takes place. They are smaller than mealy bugs, whitish, covered in white waxy threads, and very mobile, enabling them to spread to other pots. Root mealy bugs can be eliminated by a very thorough washing of the roots, and a final dip of the soil-free root ball in a solution of contact insecticide. Especially some monadeniums seem sensitive to root mealy bugs.