John, V. & Stapper, N. J. 2015. Black walnut (Juglans nigra) in riparian forests along the Rhine valley as an important phorophyte for lichens and bryophytes in Rheinland-Pfalz. — Herzogia 28: 405–429.
103 lichen and 54 bryophyte species were determined on 15 trees of Juglans nigra and 18 trees of other species in three areas of riparian forests. On J. nigra the total numbers of lichens and bryophytes reached 89 and 49 species respectively. Both lichens and bryophytes represent most classes of indicator values and all Red List categories. J. nigra is richer in both lichen and bryophyte biodiversity than the associated tree species. For all trees, the highest percentages of lichen and bryophyte species were found on twigs and branches respectively.