The following problem weeds / plants can be controlled: Japanese Knotweed (Reynoutria japonica, syn. Fallopia japonica), Marestail / Horsetail (Equisetum), Ground-elder (Aegopodium podagraria), Rhododendron ponticum, Brambles, Brushwood, Ivy (Hedera species), Senecio/Ragwort, Honey fungus (Armillaria), and felled tree stumps and most other tough woody specimens.[citation needed]