Blazing Stars (also called Gayfeathers) of the Liatris genus have general characteristics of: Stem leaves narrow and lance shaped; the flower heads, typically numbering 5 to 60 (but 160+ on a few species), each flowerhead containing a number of small tubular 5-lobed pink-purple florets. Local variations in species populations will be observed. Rootstocks are corms and rhizomes.
L. punctata is an erect native perennial forb; it is a short plant, growing to 24 inches tall on leafy ridged green stems that may have have very short hair or be smooth.
Leaves: There are both basal and stem leaves. Basal leaves are linear and (differently) shorter than those above and often whither away by flowering time. The stem leaves are alternate, with the lower ones up to six inches long but only 1/4 inch wide. Mid stem leaves become smaller and the upper leaves 1-1/2 inches long and 1/16 inch wide. Leaves arch upward, are dark green, have scarce marginal hair, a lighter color central vein with the area between the central vein and the margin covered with translucent glandular dots.
The floral array (flower area) appears as a moderately dense spike, composing the upper 1/3 of the plant, with the tightly spaced flowers mostly obscuring the stem in two of the three classified varieties. Flower heads are stalkless and open from the top of the stem downward.
Flowers: Each flowerhead holds 3 to 8 florets which have a pinkish purple 5-lobed corollas whose lobes spread when open and without hair, but the corolla tube may have hair on the inside base. The stamens number 5 and are united part way up the corolla tube and are slightly exserted but the style is lighter colored and much longer and deeply bifurcated. The phyllaries around the outside of the flower head are in 3 to 6 series, generally oblong-ovate, with tips pointed to rounded, not translucent, green in color with some purplish colors on the inner ones and finely hairy on the margins.
Seed: Fertile flowers produce a dark dry oblong 10-ribbed seed (a cypsela), 6 to 8.5 mm long, that has tawny bristly hair attached for wind dispersion. The seeds weigh about 7,000 to the ounce. Seeds need at least 30 days of cold stratification for germination.
Varieties: There are three varieties of this plant - see details at bottom of the page.
Habitat: Dotted Blazing Star grows from an elongated corm structure, which can have multiple stems and which can become rhizomatous and produce additional plants. For good plant growth, full sun and dry-mesic to dry conditions are required. This is dry prairie plant, sending down deep roots, (some measured to 16 feet) even doing well in sandy soils. Seeds germinate best in the following spring or the following fall. Otherwise a period of 30 days cold stratification is required. This blazing star blooms in August into September.
Names: The genus Liatris is an old name whose meaning has been lost. The species name, punctata, is from the Latin, meaning 'spotted' and refers to the gland dotting on the leaves, which also is the source of the common name. The alternate common names using 'Gayfeather' are frequently applied to various blazing star species. The author name for the plant classification - ‘Hook.’ is for 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. It was not usual for many North American plants to make their way to Europe where they were first classified. Hooker described this plant in 1834 in his Flora Boreali-Americana.
Comparisons: Of the shorter growing Blazing Stars with dense flower spikes and gland dotted leaves, L. spicata, Dense Blazing Star, may look similar but the leaves are larger and the phyllaries are much different - smaller, oblong and without marginal hair.
Above: The floral array of var. punctata is closely packed with flower heads. Drawing from Britton, N.L., and A. Brown. 1913. An illustrated flora of the northern United States, Canada and the British Possessions.
Below: There are 4 to 8 florets in the flower head, anthers appressed to the pistil and the style splitting into 2 lobes.
Below: The thin leaf has scarce marginal hair and is gland-dotted.
Below: The thin ascending leaves are up to 5+ inches long and only 1/4 inch wide, moderatly dense on the ridged green stem. Smaller leaves (bracts) are subtended to each flowerhead.
Below: The phyllaries of the flowerhead have hairy edges and grade from green to purplish on the inner ones. The root is an enlongated corm that produces multiple stems.
Below: The cypselae are dark, 10-ribbed and hairy with a tawny pappus.
Eloise Butler first introduced Dotted Blazing Star to the Garden in the fall of 1912 with plants sent to her by Mr. Chase of Boulder Colorado. [He was a frequent source of prairie plants in the early days of the Garden.] She planted more in 1914 and 1916. Martha Crone planted it in 1933, '34, '35, and seeds in '44 and '45 and 20 plants in '45 also and then a continuous series of planting in 1946, '47, '48, '51, '52, and '53. It was still present in the Garden at the time of her 1951 census but subsequently disappeared.
Varieties: There are three recognized varieties of L. punctata in North America: var. punctata and var. mucronata have closely spaced flower heads obscuring the stem. They differ in that var. mucronata has more phyllaries, usually 5 to 6 series, but fewer florets, usually 4 to 5, and the corms are globose in shape. Var. punctata and the third variety, var. mexicana, have corms that are elongated or becoming rhizomatous, have phyllaries in 4, sometimes 5 series and 4 to 8 florets. These latter two differ in that var. mexicana has flower heads in loose arrangement with the stems visible. It is also found only in the Southwest.
In Minnesota var. punctata is the native plant. Some references refer to an older name, L. punctata var. nebraskana. Authorities today, including Flora of North America, consider the differences described in var. nebraskana as more local ecotypes of the var. punctata and see no need for another variety. The same principle was used in incorporating the older L. densispicata into var. punctata. The MN DNR reports the presence of var. punctata in a number of counties principally in the western and southwestern part of the state but also scattered across the SE section and most counties in the metro area. In North America L. punctata is found in the central plains states east of the Rocky Mountains from Southern Canada to the Gulf coast.
In Minnesota five species of Liatris are considered native and several others have been reported but have never been collected. The native five are L. aspera, Rough Blazing Star; L. cylindracea, Ontario Blazing Star; L. ligulistylis, Large-headed (or Rocky Mountain) Blazing Star; L. punctata, Dotted Blazing Star; and L. pycnostachya, Prairie Blazing Star.
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"