Scribner's Panic Grass is a native perennial grass.
Stems are 8 to 20 inches high. They are stiff and erect above but may be bent near the base - sometimes to right angles. Stem internodes are often lustrous, purplish, usually smooth but may have fine hair.
Leaves: Basal leaves from a rosette, usually conspicuous. Stem leaf blades are widely spaced, 6 to 15 mm wide (to about 5/8 inch) and less than 10x longer than wide, mostly flat, pointed tips; the basal sheath area surrounding the stem is usually smooth on top, but the underside may have fine hair; blade margins have fine hair (ciliate). Leaf sheaths can be smooth or hairy.
The inflorescence is an open panicle with wiry but flexible branches, up to 3-1/2 inches long and almost 3 inches wide. Dichanthelium's have two periods of blooming. Primary flower heads of this species are produced in late May to early July. Secondary flower heads come from the leaf axils from late June through September. The secondary flowers remain closed and are self-pollinated and produce more seed than the first flowers. The spikelets are broadly obovoid-ellipsoid in shape, 2.7 to. 3.5 mm long and 2 to 2.4 mm wide. The small spikelets can be smooth to having sparse short hair. The upper glumes are strongly veined and have a prominent orange to purplish spot at the base.
Habitat: This species is considered the most common species of Dichanthelium on the open prairies where there is sandy or clayey soils. It is also found in disturbed ground and sometimes in open dry woodlands. The root system forms a caudex forming a clump.
Names: The genus Dichanthelium is derived from two Greek words, di, meaning 'two' and anth for 'flowering, together meaning twice flowering. The species name, oligosanthes is also from the Greek, oligos, meaning 'few' and anthes, meaning 'flowering' together referring to the few spikelets on the panicle of this species. The variety name, scribnerianum, is an honorary for American grass specialist Frank L. Scribner (1851-1938). The author names for the plant classification are: ‘Nash’ refers to George Valentine Nash (1864-1921) American botanist who worked at the New York Botanical Garden. His work was updated by: ‘Freckmann’ refers to Robert W. Freckmann (b. 1939) Professor emeritus of vascular plant taxonomy at the University of Wisconsin, Steven’s Point; Director of the Freckmann Herbarium, specialist in grasses, mainly Panicum/Dichanthelium. His co-author ‘Lelong’ refers to Michel G. Lelong, (b. 1932), American Botanist, Professor Emeritus of Biology at The University of South Alabama, founder of the Mobile Botanical Gardens, author and co-author of books on vascular plants and grasses. In years past this grass was classified as Panicum oligosanthes Schult. var. scribnerianum, before being moved out of the Panicum genus and prior to that it was classified Panicum scribnerianum. The common name of "Panic" grass is an English adaptation of the former genus Panicum.
Comparisons: D. oligosanthes is large-leaved, tufted grass, with a characteristic orange or purple colored spot usually visible on one side of the base of the spikelet. D. oligosanthes var. scribnerianum leaves are usually without hair on the top but often hairy under and have stiff margin hairs. Another variety, D. oligosanthes var. oligosanthes has slightly larger but narrower spikelets, more narrow but longer leaf blades, a smaller less visible orange spot and less distribution in the United States.
Above and below: Note the pyramidal shape of the flower head and the few small spikelets with the characteristic orangish-purplish spot at their base. Drawing above 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: The inflorescence in the flowering stage. Note the wiry branching, the orange spot and the distinct veining on the upper glumes.
Below: Leaves are less than 10 times as long as wide, margins can have fine hair, particularly near the base where the sheath is typically hairy.
Below: Stems have long hair standing straight out or ascending and the leaf margins have long hail. In the 1st and 3rd photos note the purplish tone on the stem nodes. These plants also have fine hair on the nodes.
Below: Detail of the spikelets.
Scribner's Panic Grass is indigenous to the Garden. Eloise Butler catalogued it in her early Garden records. It found in the lower Canadian Provinces and all the lower 48 states except Nevada and South Carolina. Both varieties of D. oligosanthes are found in Minnesota with distribution in over half of the counties, but most absences are in the northern half of the state. The DNR no longer tracks these two varieties by county. Eleven species of Dichanthelium are known in Minnesota plus three that have been reported but without collected specimens.
The other species of Panicgrass found in the Garden is Hairy Panicgrass, or Western Panicgrass, D.acuminatum.
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"