The Stiff Gentian is an erect biennial growing to 2 feet high on 4-angled smooth stems, which on large plants may branch at the top. Stems become purplish with age, especially near the base.
The leaves are opposite, medium green, smooth, ovate shaped, twice as long as wide, with parallel veins, stalkless or slightly clasping, tapering to the tip, bases tapered also but more broadly. Leaves at the top of the stem are smaller and reduce to bracts in the inflorescence.
The inflorescence is a terminal umbellate shaped cluster of flowers at the top of the erect stem and sometimes also from the upper leaf axils where the clusters are at the tip of ascending side branches. There are 2 small bracts under each cluster. The terminal cluster can have 3 to 7 flowers, typically 5, hence the species name and alternate common name of "Five-flowered Gentian". The axillary clusters have fewer flowers.
The flowers have a tube shaped corolla of 5 bluish-purple lobes forming petals that do not have a connecting fringe such as the Bottle Gentian does. The lobes are triangular in shape with pointed tips which frequently close together forming a point. The flower calyx is much shorter than the corolla, bell-shaped and has five finger-like lobes with pointed tips. The reproductive parts include 5 stamens the rise from around the base of the ovary and alternate with the petals. Filaments are white with whitish-purple anthers. The ovary has single style that has a branched curled tip. The stamens are held against the ovary (but not united with it) for up to 1/3 of their length, with the anthers surrounding the style. As the ovary enlarges with fertilization it becomes ovate to elliptical, somewhat flattened while the stamens wither away. Neither the petals or the calyx lobes (sepals) have any hair. As with most species in the Gentianaceae, the flower petals can sometime shade to whitish. Each flower is less that one inch long and is held erect.
Seeds: Fertile flowers produce a 2-sectioned 5-lobed seed capsule that splits when mature to release numerous very small flattened brown seeds to the wind. They have no pappus but are light enough (180,000 to the ounce) for wind distribution. Seeds need light for germination plus 60 days of cold stratification and should be surface sown.
Habitat: Stiff Gentian grows in well drained upland soils of bluffs, prairies and open woods with full sun to partial shade. Moisture conditions should be mesic to dry mesic It tolerates wet-mesic to mesic conditions. The root system does not cause the plant to spread. Reproduction is by seed.
Names: Previously Stiff Gentian was classified as Gentiana quinquefolia but is now in the genus Gentianella which has come into use to describe the dwarf gentians. There are 256 species in the genus. The word is a diminutive of Gentiana, which is named after King Gentius of Illyria who, according to Pliny, discovered that the roots of certain Gentian species have medicinal qualities for treating malaria. See page bottom for text about the name 'Agueweed'. The species name quinquefolia is Latin referring to 'five flowers' as explained up above.
The author names for the plant classification are: First to classify was "(L.)" which refers to Carl Linnaeus (1707-1778), Swedish botanist and the developer of the binomial nomenclature of modern taxonomy. His work was amended by ‘Small’ who is John Kunkel Small (1869-1938), American Botanist, first curator of the New York Botanical Garden, best known for Flora of the Southeastern United States.
Comparisons: Stiff Gentian has bottle shaped flowers and is thus similar in appearance to the white flowered Plain Gentian, Gentiana alba, and the blue flowered Bottle Gentian, Gentiana andrewsii, except that these two have flowers that are always closed and much larger and have a fringe between the petals. There are two subspecies: subsp. occidentalis and subsp. quinquefolia. The former occupies the western section of the plants native range, from Ohio westward. The latter has a smaller calyx.
Above: The inflorescence with a terminal cluster of flowers and numerous axillary flowers. Note the curled stigmas of the styles in some of the upper flowers. Drawing from Britton, N.L., and A. Brown. 1913. An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols. Charles Scribner's Sons, New York.
Below: 1st photo - Flowers mostly in an open position. 2nd photo - Leaves are opposite, stalkless to slightly clasping, with parallel veins and a pointed tip.
Below: This group of clusters has a number of flowers with the petal tips in the closed position forming a point.
Notes: Stiff Gentian first arrived in the Wild Flower Garden in 1914 when Eloise Butler brought in plants from Wisconsin. She added more in 1918. Martha Crone planted it in 1951, '53' and '56 and sowed seeds in 1952 and '54. Cary George was the last to plant it - in 1993. Within Minnesota it is found in the wild in only 11 counties, all in the SE quadrant of the state, and all south of the Metro area. The plant native to the state is subsp. occidentalis.
In North America the plants range is from the Mississippi River corridor except Louisiana, east to the Atlantic Coast. In Canada it is known only in Ontario.
G. quinquefolia is one of only two species of Gentianella in Minnesota; the other species being G. amarella, Autumn Dwarf Gentian, which is on the state "Special Concern" list. The other Gentians are classed in the Genitana genus and include Gentiana andrewsii, Bottle Gentian, G. affinis, Northern Gentian; G. flavida, Yellowish Gentian - (sometimes called Plain Gentian and listed as G. alba); G. puberulenta, Downy Gentian; and G. rubricaulis, Great Lakes Gentian. The second is on the state special concern list. Billington's Gentian, Gentiana x billingtonii is known only from one small population on a railroad line in Dakota County. Several other species were previously reported but there are none ever collected or the collection is very old.
Medicinal Lore: All known Gentian species have intensely bitter properties in the root. Over the centuries in Europe and Asia this has led to the development of herbal medicines, particularly from the old world species G. lutea. Gentian bitters are prepared from the dried root in use for general debility, weakness of the digestive system and lack of appetite. An alcoholic drink can even be prepared from the roots as once properly prepared and distilled, the distillate contains alcohol. The American species of gentian, have similar properties to the European species. You will find much detail in Mrs. Grieve's Book. (Ref. #7). The root of G. quadquefolia has been used to treat fit of fever or shivering or shaking chills, accompanied by malaise, pains in the bones and joints, hence it's alternate common name of "Agueweed".
References: Plant characteristics are generally from sources 1A, 32, W2, W3, W7 & W8 plus others as specifically applied. Distribution principally from W1, W2 and 28C. Planting history generally from 1, 4 & 4a. Other sources by specific reference. See Reference List for details.
Identification booklet for most of the flowering forbs and small flowering shrubs of the Eloise Butler Wildflower Garden. Details Here.
Friends of the Wild Flower Garden, Inc. Text and photos are by G. D. Bebeau unless otherwise credited. "www.friendsofthewildflowergarden.org"