Fuller's Teasil, Dipsacus fullonum, a common weed, particularly in damp or
low-lying areas. It's pollinated by bumblebees, like many thistles, but it is not a
thistle -- it's in its own family, Dipsacaceae. Dip'sacus: from the Greek dipsa, "thirst,"
from the conjoined leaf bases that in some species hold water (eg, this genus, Dipsacus).

Note about bumblebees: One genus, Bombus, with 30+ sub-genera and 200+ species world wide.
They collect both pollen and nectar, but do not make honey. Nectar is stored as a thin unprocessed
liquid that can last only a few days; thus, no food supply through winter. Sometimes they bore
through the calyx of a plant to get at the nectar directly. They leave a scent mark which fades after
a while; may travel two miles to flowers. They are semi-social, with loose hive groups; queen stores
sperm like a honey bee and may choose to fertilize an egg or not; unfertilized eggs make drones;
stingers are not barbed and can be used for repeated stings; only honeybees have barbed stingers.