This page covers two plants as both are similar in appearance. Both are erect native perennials.
Stems of Great Indian Plantain (A. reniforme) have 6 to 8 angles, are grooved and have a purplish tint as the example in these photos shows. Stems of Pale Indian Plantain (A. atriplicifolium) are usually green, without angles, smooth, some minor striations and sometimes with a whitish bloom. Stems of both can be 3 to 9 feet high and unbranched below the floral array.
Leaves: Larger upper leaves of both plants have 3 to 5 main veins veins palmately arranged. On Great Indian Plantain the upper leaves are fan shaped with pointed teeth and green on both sides. Pale Indian Plantain has rounded triangular shaped upper leaves that are pale beneath. The basal leaves of both are much larger, ovate to heart-shaped, lobed or with large teeth.
The floral array of both have erect tubular whitish flowers of indistinguishable parts, that appear in somewhat flat topped corymbs atop the stems.
The flowers, while being in the Aster family, do not have ray florets, only disc florets which number 5, are bisexual and fertile. The heads are cylindric in shape, those of A. atriplicifolium 8 - 10 mm wide and those of A. reniforme slightly wider, 10 - 13 mm. The corollas are greenish or creamy white, with funnel shaped throats that have 5 pointed spreading lobes. Five stamens have filaments that surround the single style which branches at the tip. Around the outside of the flower head are 5 phyllaries, greenish-white, ovate to oblong-linear in shape which spread when the flower opens. The midveins of the phyllaries of either plant are not winged as are some of the species of Arnoglossum.
Seeds: Fertile flowers produce a dry cypsela, 4 to 5 mm long, brown to purplish in color, with an attached white bristly pappus for wind dispersion. The cypselae of A. reniforme are 4 to 5 ribbed, while those of A. atriplicifolium are 8 to 10 ribbed. See notes below for distribution of these plants.
Habitat: Both species can be found in open woods, roadsides, prairies, where there is full to at least partial sun. A. reniforme prefers a more moist environment than A. atriplicifolium. The root system is rhizomatous.
Names: Botanists have reclassified these plants in recent years. Both species were formerly in the genus "Cacalia". Great Indian Plantain was formerly Cacalia muhlenbergii and Pale Indian Plantain was formerly Cacalia atriplicifolia. The plant census of the Garden simply lists the plant as Cacalia sp. The genus name Arnoglossum is derived from two Greek words, arnos, meaning 'lamb, and glossum, meaning 'tongue' and together are a reference to an old name for plants of the Plantago family. The species names, reniforme, means 'kidney shaped' and is probably a reference to the shape the lower leaves can take; and atriplicifolium refers to the plant having leaves like the Atriplex genus.
The author name credited for the current plant classification on both species is ‘H.Rob’ which refers to Harold E. Robinson (1932 -) American botanist, specialist in the Asteraceae. The first person credited with publishing the classification on A. atriplicifolium (in 1753 as Cacalia atriplicifolia) was '(L.)' which refers Carl Linnaeus (1707-1778), Swedish botanist and the developer of the binomial nomenclature of modern taxonomy. Robinson revised in 1974. On A. reniforme the first to classify was ‘Hook.’ who was William Hooker, (1785-1865), English Botanist, author, collector, Professor of Botany at the University of Glasgow and the first director of the Royal Botanic Garden at Kew. Robinson revised in 1980.
Comparisons: There are two large plants with very large palmate leaves and a floral array of clusters of small white flowers that may confuse. First is Glade Mallow, Napaea dioica - there the leaves are somewhat round in outline with 5 to 9 deep palmate lobes which are coarsely toothed. The small white flowers are in small clusters but have open faces. Second is Cow Parsnip, Heracleum maximum - here the large leaves are compound with 3 palmately lobed leaflets. The small white flowers are also open face and in a compound umbel.
Above: Photo - The floral array and upper stem of Great Indian Plantain. Drawing is of Pale Indian Plantain 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 - the flowers in the array are arranged in corymbs. 2nd photo - The pointed fan shaped leaves with palmate veins of Great Indian Plantain. and the angular stem.
Below - Great Indian Plantain: 1st photo - The angular and grooved stem. 2nd photo - The seeds of the Indian Plantains are 4 - 5 mm long cypselae, ribbed, with bristly white pappus for wind dispersion.
Below: The flat-topped corymb arrangement of the flowers. Plant photos shown are from the end of June, early July.
Below: Pale Indian Plantain: 1st photo - lower leaf, 2nd photo - flower umbel prior to flowers opening. 3rd photo - The smooth un-angled stem.
Below: The large floral array with many flower umbels of Great Indian Plantain.
Below: The seed heads of August beginning to open and release the white bristly seeds of Great Indian Plantain.
Notes: As to the Wildflower Garden, neither plant was on Martha Crone's 1951 inventory of plants in the Garden or on Eloise Butler's 1907 plant list. Great Indian Plantain has been introduced since then. Photos of it (above) are from 2009. Great Indian Plantain, A. reniforme, is native to Minnesota, reported in the 7 counties that make up the SE corner of the state where they are across the Mississippi River from Wisconsin's reported native population. Pale Indian Plantain, A. atriplicifolium, while reported as being in the state has no confirmed reporting and the University of Minnesota's Checklist of the Vascular Flora of Minnesota (Ref. #28c) reports that the evidence of it being in the state may be to a misidentified specimen as there are no specimens in the U of M Herbarium. There is no reported population in Wisconsin that is close the Minnesota, the only reported population is in the eastern section of the state. The only other species of Arnoglossum reported in Minnesota is A. plantagineum, Groove-stemmed Indian Plantain, found only in the southern counties. It has winged phyllaries and that is a species that Eloise Planted in 1923 and later.
In North America A. artrplicifolium is found in the eastern half of the U.S. except New England. A. reniforme has less distribution, being found from the Mississippi River east to the coast, but no further north than Pennsylvania in the eastern states and not along the Gulf Coast. Neither are known in Canada.
Species rarity: Both A. plantagineum and A. reniforme are on the Minnesota DNR "Threatened List".
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"