''Carex amphibola'', known as gray sedge, is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

in the family

Cyperaceae The Cyperaceae () are a family of graminoid (grass-like), monocotyledonous flowering plants known as wikt:sedge, sedges. The family (biology), family is large; botanists have species description, described some 5,500 known species in about 90 ...

. It was first formally named in 1855. ''Carex amphibola'' is native to the eastern United States and Canada. ''Carex amphibola'' is commonly confused with '' Carex grisea'', which has somewhat greener

perigynia In botany, a perigynium (plural: perigynia), also referred to as a utricle, typically refers to a sac that surrounds the achene of plants in the genus ''Carex'' (Cyperaceae). The perigynium is a modified prophyll, also known as a glume, which is t ...

with more rounded tips, versus the gray-green coloring and angular tips of ''C. amphibola'' perigynia. The perigynia of ''C. amphibola'' are somewhat more clustered and spreading at maturity, while those of ''C. grisea'' are strongly ascending. ''Carex amphibola'' grows in mesic deciduous forests, often in

loam Loam (in geology and soil science) is soil composed mostly of sand (particle size > ), silt (particle size > ), and a smaller amount of clay (particle size < ). By weight, its mineral composition is about 40–40–20% concentration of sand–si ...

y areas near streams.

References

amphibola Plants described in 1855 Flora of Northern America {{Carex-stub