Pollination Ecology of Asclepias Ovalifolia

Abstract

Ants have traditionally not been considered effective pollinators of milkweeds due to their inability to remove pollinia. However, the observation of the ant species Formica obscuripes successfully removing pollinia of the oval-leaved milkweed Asclepias ovalifolia prompted an experiment to test the ability of these ants as pollinators for this milkweed. Three insect exclusion treatments ("no insect," "ant only," and "all insect") were imposed. Data was recorded on subsequent removal and deposition of pollinia, fruit set, and seed set.