As this is a parasitic species, all flower visits will be for nectar only.
Celary, Fijal and Kosior (2003) (citing Loken (1984) and Pittioni (1942)) list the following plants as nectar sources in Norway: Salix (Salicaceae); Ranunculus (Ranunculaceae); Geranium sylvaticum (Geraniaceae); Cirsium, Taraxacum and Solidago virgaurea (Asteraceae). Alpine populations are cited as visiting Anthyllis vulneraria (Fabaceae); Leontodon montanus, Carduus personata, Cirsium spinosissimum, Cirsium appendiculatum (Asteraceae); Erica spp. (Ericaceae); Saxifraga aizoiodes (Saxifragaceae) and Thymus sp. (Lamiaceae)(Beaumont 1958; Pittioni 1942)
A specimen found in the Carpathian mountains of southern Poland was flound at flowers of Senecio fuchsii (Asteraceae)(Celary, Fijal and Kosior, 2003)
In Spain, Ornosa & Ortiz-Sánchez (2004) list the following plant families as providing forage: Scrophulariaceae.