''Triosteum perfoliatum'', commonly known as perfoliate tinker's-weed, late horse gentian, common horse gentian, perfoliate-leaved horse-gentian, feverwort, and wild coffee, 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 ...

belonging to the family

Caprifoliaceae The Caprifoliaceae or honeysuckle family is a clade of dicotyledonous flowering plants consisting of about 860 species in 33 to 42 genera, with a nearly cosmopolitan distribution. Centres of diversity are found in eastern North America and easte ...

(honeysuckle). It is found in eastern and central North America. The yellow-orange berries can be dried, roasted, ground, and used as a

coffee substitute Coffee substitutes are non-coffee products, usually without caffeine, that are used to imitate coffee. Coffee substitutes can be used for medical, economic and religious reasons, or simply because coffee is not readily available. Roasted grain ...

Description

''T. perfoliatum'' grows as an unbranched, light green, hairy stem up to tall. Pairs of opposite leaves are joined around the stem, with each pair occurring at a 90-degree angle from the next one along the stem. Each leaf is up to long and across, with smooth margins. The flowers are reddish-brown and are clustered on very short stems in the

axils A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, f ...

of the leaves. They are tubular with five small lobes. The fruit resembles small oranges and remains on the stalks in the fall. Each

drupe In botany, a drupe (or stone fruit) is a type of fruit in which an outer fleshy part (exocarp, or skin, and mesocarp, or flesh) surrounds a single shell (the ''pip'' (UK), ''pit'' (US), ''stone'', or ''pyrena'') of hardened endocarp with a seed ...

contains three black nutlets.

Etymology

The genus name ''Triosteum'' is a shortened form of the Greek word "triostospermum", meaning "three stony seeds". The specific epithet ''perfoliatum'' is from the Latin meaning "through the leaf", referring to the way the stem comes through each pair of joined leaves.

Distribution and habitat

''T. perfoliatum'' is native in the United States from Nebraska to the west, Louisiana to the south, Massachusetts to the east, and the Canadian border to the north. In Canada, it is native in Ontario, where it is an endangered species. In Louisiana, it is possibly

extirpated Local extinction, also extirpation, is the termination of a species (or other taxon) in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinctions. Local extinctions mark a chan ...

. It is extremely rare in both Massachusetts, where it is endangered, and Rhode Island, where it is a species of concern. It can be found in open woods on hillsides or valleys in dry areas.

Ecology

The flowers of ''T perfoliatum'' bloom May to July and attract various bees, particularly bumblebees (''

Bombus A bumblebee (or bumble bee, bumble-bee, or humble-bee) is any of over 250 species in the genus ''Bombus'', part of Apidae, one of the bee families. This genus is the only Extant taxon, extant group in the tribe Bombini, though a few extinct r ...

'' spp.) and anthophorid bees (''

Anthophora The bee genus ''Anthophora'' is one of the largest in the family Apidae, with over 450 species worldwide in 14 different subgenera. They are most abundant and diverse in the Holarctic and Africa Africa is the world's second-largest and sec ...

'' spp.). It is a larval host for ''

Hemaris diffinis ''Hemaris diffinis'', the snowberry clearwing, is a moth of the family Sphingidae. This moth is sometimes called "hummingbird moth" or "flying lobster". This moth should not be confused with the hummingbird hawk-moth of Europe. Adults It is ...

'', the snowberry clearwing moth.

References

{{Taxonbar, from=Q17435440 Caprifoliaceae Flora of Eastern Canada Flora of the Northeastern United States Flora of the Southeastern United States Flora of the North-Central United States