Iris setosa

Appearance

''Iris setosa'' is similar in form to a miniature Japanese iris, or a dwarf version of ''Iris sibirica'' but a shorter lived version.

The shallowly rooted, large, branching rhizomes spread over time to create large clumps. The rhizomes are grey-brown, thick, and are covered with old fibrous leaf remains .

It has branched stems, which are very variable in height, ranging from 10 cm up to 1 m tall. The larger plants can grow beyond the height of the leaves. The roundish stems are between 1.5–9 cm in diameter with 1 to 3 branches.

''Iris setosa'' has mid-green leaves, which are grass-like, and lanceolate . They have a purplish tinged base and the leaves can measure 30–60 cm long by 0.8–2.5 cm wide.

The plant has 3–4 flowers per stem and it blooms between June and July.

The large flowers are between 5–8 cm across, usually 7–8 cm, and come in a range of shades of blue, which can depend on the location. and range from violet, purple-blue, violet-blue, blue, to lavender. Very occasionally, there are pink or white forms.

Like other irises, it has 3 pairs of petals, 3 large sepals , known as the 'falls' and 3 inner, smaller petals , known as the 'standards'. The sepals can be deeply veined dark purple with a yellow-white signal . The standards are so small, that they are reduced to bristles. Which gives the flower, a flat, three petal appearance.

The perianth tube is about 1 cm long, normally dark blue-violet to red-purple with darker veins.

The plant is self-fertile, being hermaphrodite and it is pollinated by insects. The stamens are about 2 cm long, the anthers are purple and the ovary about 1 cm long.

After the flowers have finished blooming, the seeds ripen between August and September. They are cased within a green seed capsule, which is loculicidal, or cylindrical, , which turns pale brown when it ripens. It has 6 ribs along its sides.

The pale brown seeds have a distinct raised raphe the length of one edge.

Distribution

This is the only iris species that is native to both Asia and North America.

Status

It was on the Red List of Japanese endangered plants .

Habitat

This is the only iris species that is native to both Asia and North America.''Iris setosa'' is tolerant of many kinds of habitats. It can be found in bogs , meadows, beside rivers , on lake shores, , beaches, dunes, headlands and light woodland. It can grow in sand or gravelly soils. Although, normally considered a wetland plant, it does well in dry soil, too. It is normally found at 1,500–2,500 m above sea level.

Uses

Herbalists have used the rhizome of ''Iris setosa'' for centuries as an ingredient in various medicines, . However, all parts of ''Iris setosa'' are poisonous. The rhizome contains iridin which is an oleoresin. This substance can affect the liver and digestive organs. It can cause allergic reactions such as severe rashes. It can also cause vomiting or diarrhea. It was used in an ingredient in a poison to put on arrowheads.

Although the plant is poisonous, its starchy roots can be made safe for human consumption via cooking. It is cultivated in Japan for its edible root. The Aleut also made a drink from the roots, to be used as a laxative, but the Iñupiat considered the whole plant poisonous. It is used to make a tincture, when used in small amounts to help soothe lymphatic swelling. It can be combined with arnica as an herbal oil to relieve bruises.

Some Inuit tribes in Alaska also roasted and ground the seeds of the iris to be used as a coffee substitute.

The flower petals can be used to create a violet-blue dye, when it is used with a chrome mordant . They are also were used as a grass dye for baskets. The rhizomes can also be used to extract a perfume .