Verbascum phlomoides L. (C, E and S-Eur.) – A regular but usually ephemeral alien (although seen all years in rather many places). Known at least since 1811 (Durand 1899) and recorded in widely scattered localities throughout the country.
Verbascum phlomoides is usually found by roadsides and in grasslands, abandoned clay and sand pits, coalmine heaps, by railway tracks and canals, on river banks, rough ground in cities and port areas, etc.
Belgian records of Verbascum phlomoides mostly seem to be associated with gardens but some findings in port areas clearly refer to unintentionally introduced plants.
It is usually easily distinguished from the similar Verbascum densiflorum (both with more or less equally large flowers) by the non-decurrent leaves. In some populations plants with slightly decurrent leaves are found. The identity of such plants remains obscure: they either are hybrids or suggest that both species are best accepted as one variable species with decurrent or non-decurrent leaves (Mosseray 1935-36). However, this point of view is rarely followed by contemporary taxonomists.
In Belgium, hybrids have been documented with Verbascum densiflorum (V. xinterjectum Pfund) and V. nigrum (V. xbrockmuelleri Ruhmer).
The very similar Verbascum longifolium is cultivated as an ornamental and might have been overlooked. Its floral bracts are narrower, pedicels longer and basal leaves more whitish tomentose (not grayish) and up to 60 cm long.
Durand T. (1899) Phanérogames. In: De Wildeman E. & Durand T., Prodrome de la flore belge. A. Castaigne Editeur, Bruxelles: 1112 p.
Fuchs H.P. (1963) Zur Verbreitung und Nomenklatur von Verbascum phlomoides sensu auct. Verh. Naturf. Ges. Basel 74.
Kent D.H. (1949) Verbascum phlomoides L. Watsonia 1: 120.