Athyrium
filix-femina
Lady Fern
This is the most common deciduous fern of the northwestern lowland
forests. It's leaves die back in the winter and reappear in
early
spring. The overall outline of the fronds is narrower at the
base, increases in the middle and then tapers to a point.
Superficially similar is Wood Fern, but its leaves are
triangular: widest at the base and then taper to a point.
This fern is an excellent one in which to study the typical
plant
"alternation of generations" life cycle, where each plant alternates
between the sporophyte phase and the gametophyte phase.
Sporophytes release spores that grow into gametophytes (see here).
Gametophytes produce gametes that unite to form sporophytes (see here).