Table 1.

Four selected bee species, sampled localities, degree of floral specialization, and the main host‐plant from the sampled population. Classification APGIII (2009)

Bee species	Locality	Specialization	Plant species analyzed
Andrena vaga	Belgium, Blaton	Specialist (Westrich, 1989)	Salix caprea (Salicaceae) Salix fragilis (Salicaceae)
Anthophora plumipes	Belgium, Malines	Generalist (10 plant families; Westrich, 1989)	Lamium album (Lamiaceae) Pulmonaria officinalis (Boraginaceae) Symphytum officinale (Boraginaceae) Salix caprea (Salicaceae)
Colletes cunicularius	Belgium, Blaton	Generalist (11 plant families; Müller & Kuhlmann, 2008)	Cytisus scoparius (Fabaceae) Prunus avium (Rosaceae) Salix caprea (Salicaceae) Sorbus aucuparia (Rosaceae)
Osmia cornuta	Belgium, Mons	Generalist (8 plant families; Westrich, 1989)	Erica carnea (Ericaceae) Muscari botryoïdes (Asparagaceae) Pyrus communis (Rosaceae) Salix caprea (Salicaceae)