Formica rufa

Image Credit: Jukka

Ants (Formicidae) – omnivores – the genera Tapinoma and Formica are the primary visitors. Tapinoma are primarily searching for nectar, hence the common name “sugar ants”. Almost without exception they favor simple bowl-shaped flowers with separate petals which they often extract from below the flower directly into the nectary. At our site Tapinoma are particularly active nectar-feeders during the very early spring on flowers of vine maple (Acer circinatum).

Formica flower-visiting behavior is often associated with aphid “domestication” and has negative pollination effects by chasing other flower-visitors away from their aphids or from flowers they are actively feeding upon themselves (often the carrot family (Apiaceae) or other complex inflorescences particularly ocean-spray (Holodiscus) and elk-clover (Aralia). There is no question that individual ants often spend long periods on flowers and probably become covered in pollen, but their pollination potential is extremely limited to “geitonogamy” (= selfing), since their ability to actually carry pollen between different plants is severely limited.

Ant1 Ants2 Ants3

Ants4 Ants5

Ants, even the flying sexuals, are characterized by “elbowed antennae” that have a right-angled joint between an immense first segment and the rest of the antenna (see upper middle picture). Tapinoma (bottom 2 pictures) are normally tiny (<3mm), whereas Formica are usually 4-7mm long. Notice the Formica ants and their “domesticated” aphid  colony.