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Lovely Liatris

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Published on: Jul. 2, 2002

Last revision: Nov. 12, 2010

When pioneers crossed the Missouri prairies in the early 1800s, the magenta spikes of blazing stars were a welcome sight. Their lush blooms rising out of the sun-baked grasslands in July and August provided a visual treat to weary travelers.

If your wanderlust takes you across Missouri this summer, look for our lovely Liatris species. You may find them from the Glaciated Plains in the north to the Ozarks in the south.

Missouri is home to eight stunning species in the genus Liatris, the plant group to which blazing stars, also known as gayfeather or button snakeroot, belong. Although each species is distinct, all are sun-loving and drought-tolerant. Liatris species are adapted to prairies, glades and open woodlands. These natural communities usually have dry soil and are saturated by direct sunlight.

In shade-dappled woodlands, a few plucky blazing star plants may grow for years, blooming only when windfalls allow more sunlight to reach the woodland floor. Liatris species also rebound after prescribed fires or cedar-cutting restore these communities to their more open, original character.

How to identify Liatris species

All Liatris species have numerous narrow leaves along the stem and purple, pink, magenta or occasionally white flower clusters. They are perennials and have either fleshy corms from which fibrous roots grow, or thick, branching taproots, some attaining depths of 15 feet.

In all species, each flower is tubular with five lobes and two threadlike styles that protrude from the petals. The style is the structure through which pollen reaches a flower's ovary.

Depending on the species, each flower cluster may contain thee to 40 individual flowers. Some blazing stars have many flower clusters that form a solid spike of color. Others have solitary clusters or just a few.

The best way to tell the four most widespread species apart is to look at the tiny bracts. These are the small leaflike structures that overlap like roof shingles below each small cluster of flowers. The collective term for these bracts is "involucre." Rough blazing star, for example, has rounded bracts with the edges rolled back and papery tips. Scaly blazing star has pointy bracts that bend back sharply. Other blazing stars are restricted to certain parts of the state, so their location helps you identify them.

The four most common blazing stars

Gayfeather or Blazing star - Liatris pycnostachya

Perhaps the best known blazing star species, Liatris pycnostachya, is widespread in Missouri and has been commercially cultivated. It grows in moist to dry prairies and occasionally in glades and open woodlands. The flowers bloom from mid-July to early August.

The unbranched plants are usually from 20 to 60 inches tall. They are covered with narrow leaves that can be one-foot long and up to one-half inch wide at the base of the plant. They are smaller higher up the stems. The flower clusters crowd together to form a solid, purplish pink spike that can be more than a foot long. In fact, the species name, pycnostachya, means "thick-spiked."

Each flower cluster usually has five to 10 flowers. The stems, flowering spikes and bracts are usually hairy. The bracts curve backward and have pointed tips.

Rough blazing star - Liatris aspera

Liatris aspera has flower clusters arranged alternately along the spike, with space between the clusters. There are 16 to 35 individual flowers per cluster. The unbranched stems can grow up to 4 feet tall. The plants have short hairs on the stems and leaves, or are hairless. The leaves at the base of the plant can be up to 16 inches long and 2 inches wide. They are shorter up the stems.

You can usually identify this plant by its height and the arrangement of the flower clusters, but to be sure, look at the bracts. They are rounded, with papery edges that are rolled backward.

Liatris aspera is more widespread than L. pycnostachya and grows in prairies, savannas, glades and dry, open, rocky woods. It usually blooms in late summer and early fall. The second part of this plant's name, aspera, means rough, and probably refers to the texture of the leaves.

Cylindrical blazing star - Liatris cylindracea

The word cylindracea refers to the cylinder-shaped flower heads of this species. This delicate blazing star grows mostly in southern and central Missouri and is much smaller than the previously described species. It grows on dolomite glades and occasionally in rocky open woodlands and prairies. It blooms from midsummer to early fall.

The plant grows up to 2 feet tall and has one to 10 flower heads per plant. Each flower head has 10 to 35 individual flowers.

The leaves and stem are almost always without hairs. The leaves at the base of the plant are short, become longer in the middle, then shorter at the top of the stem. The bracts of each flower head are pointed and stand up straight, rather than spreading outward.

Scaly blazing star - Liatris squarrosa

At first glance, this species might be mistaken for L. cylindracea, but there are some distinctions. Squarrosa means "spreading," and refers to the bracts. They are pointed like those of L. cylindracea, but instead of standing up straight, they are bent backward, giving the flower heads a spiny or scaly appearance. L. squarrosa often is hairy, while L. cylindracea usually is not.

L. squarrosa can grow to 2.5 feet tall and usually has fewer than 10 flower heads per plant. They are arranged alternately along the top portion of the plant, and the topmost flower head is usually larger than the others. There are 20 to 40 individual flowers per flower head. Scaly blazing star grows in rocky or dry open woods, prairies, savannas, glades and ledges along bluffs. It blooms from June through September.

Two Liatris species with limited distribution

Dotted blazing star - Liatris punctata

In Missouri, dotted blazing star grows only in counties along the Kansas and Nebraska borders. It blooms in late summer and early fall on loess hill prairies in northwestern Missouri and on prairies in a few counties on the western edge of Missouri.The word punctata means "dotted," and refers to numerous tiny dots on the underside of the plant's leaves and bracts. Each dot contains resin that probably deters animals from eating the plant.

Dotted blazing star grows about 3 feet high. It has so many stems it resembles a low shrub. At the top of the stems, flower heads are packed densely together into a flowering spike.

Most flower heads have three to eight individual flowers. The stems are covered with stiff, narrow leaves that grow all the way to the top of the spikes. The plants are usually smooth, except that the edges of the leaves often have a line of tiny hairs.

Bottlebrush blazing star - Liatris mucronata

This species gets its common name from its leafy stems, which resemble bottle brushes. Although it shares this characteristic with dotted blazing star, bottlebrush blazing star lacks dots on its leaves and bracts.

Also, this species grows primarily on dolomite glades in the White River Hills in southwest Missouri. It has also been found in Texas County.

Bottlebrush blazing star grows up to 2.5 feet tall and often has several stems rising from a common base, giving it the appearance of a low shrub. The leaves are hairless and have abruptly pointed tips. The tip of the leaf is known as a "mucro."

Each flower head along the spike contains three to six individual flowers. This species also differs from dotted blazing star in that it has a large corm with fibrous roots, whereas dotted blazing star has long taproots.

Two uncommon blazing stars

Two species of Liatris occur in just a few locations in the state.

Liatris scariosa and L. squarrulosa in general resemble L. aspera, with their alternately arranged flower clusters along the flowering spike. However, the flower clusters of the two species are attached to the spike with short stalks, whereas the flower clusters of L. aspera are directly attached to the spike.

Also, the bracts of the two species are usually pointed and spreading or curved backward. The bracts of L. aspera are rounded, with papery edges that are rolled backward. L. scariosa may become more well known to Missourians as it has recently become available at some plant nurseries.

L. scariosa grows in rocky, open woods, prairies and gravelly areas along streams. L. squarrulosa grows in rocky open woods and glades. Both species bloom in late summer and early fall.

Gardening with Liatris

With their abundant flowers and tolerance of poor soils and dry conditions, blazing stars make dramatic and fairly care-free additions to a garden. You can grow blazing stars either by propagating them from seed or buying plants. Several nurseries in Missouri sell native blazing star seed and plants.

You also can collect seeds from roadside blazing stars and propagate them yourselves. If you grow blazing stars from seed, expect to wait two to three years before the young plants begin to flower. Nurtured in a garden, blazing stars grow taller than in the wild. If they are not part of a dense planting, you may need to stake the plants to keep them from flopping over.

To find nurseries selling blazing star seeds or nursery-grown plants, check out the  the Conservation Department's Grow Native! program.

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