Hybridises with : Other Willowherbs, namely : New Zealand Willowherb, Hoary Willowherb, Alpine Willowherb, Marsh Willowherb, Square-stalked Willowherb, Great Willowherb, Pale Willowherb, Short-fruited Willowherb. All one big happy family!
Lookee-Likees : Many other Willowherbs!
