Flower-Visiting Insects
of Giant Ragweed

Ambrosia trifida (Giant Ragweed)
(The monoecious flowers are wind-pollinated; bees collect pollen, the wasp merely explores the flowers, ants feed on nectar-like fluid exuding from the pustular hairs on petioles of young leaves, beetles feed on pollen or feed on stray pollen or feed on nectar-like fluid exuding from the pustular hairs on petioles of young leaves; all of these insects are non-pollinating as they visit only staminate flowers or pustular hairs on petioles; observations are from Robertson and Wilhelm & Rericha)

Visitors of Staminate Flowers:

Bees (long-tongued)
Apidae (Apinae): Apis mellifera cp np fq (Rb)

Bees (short-tongued)
Halictidae (Halictinae): Lasioglossum illinoense cp np (WR)

Vespidae: Vespula germanica exp np (Rb)

Chrysomelidae: Diabrotica virgifera fp fsp np (WR); Mordellidae: Mordella atrata fp np (WR); Phalacridae: Olibrus semistriatus fp np (WR)

Visitors of Extra-floral Nectaries:

Formicidae: Camponotus nearcticus sn np (WR), Camponotus pennsylvanicus sn np (WR), Crematogaster cerasi sn np (WR), Dolichoderus plagiatus sn np (WR), Lasius alienus sn np (WR), Formica incerta sn np (WR), Formica montana sn np (WR), Formica pallidefulva sn np (WR), Formica subsericea sn np (WR), Myrmica latifrons sn np (WR), Prenolepis imparis sn np (WR)

Mordellidae: Mordella atrata sn np (WR)