Taiwan Iris
Characteristics:
Information by: Astere, Felix, & Josiane
Iris formosana
Iris formosana is a plant species in the genus Iris, it is also in the subgenus Limniris and the section Lophiris. It is a rhizomatous perennial plant, from Taiwan, it has large white or lilac flowers. It is commonly known as the 'Taiwan iris'. It is cultivated as an ornamental plant in temperate regions.
Description
It has thick rhizomes with slender branching stolons It has the habit of creating large clumps of plants
It has herbaceous erect, sword shaped, rigid,[4] leaves that are greyish-green on one side and bright green on the other side. They can grow up to between 30-40 cm (12-16 in) long and 2-2.5 cm wide. The leaves have between 3 - 5 veins or ribs. They are similar to Iris japonicas leaves.
It has a thick, flowering stem that can vary, between 15-90 cm (6-35 in) long. It is normally between 30-40 cm (12-16 in) long.The stems are smaller than Iris confusa stems.[13] It has between 4 and 5 branches.
The stems have 4-6 spathes (leaves of the flower bud), which have membranous margins
The stems (and branches) hold between 3 and 5 flowers, in spring, between April to May (in the UK), or between March and April (in Europe).
The flowers are similar to Iris japonica but with shorter basal leaves and larger white flowers
The flowers are 7-10 cm (3-4 in) in diameter, and come in shades of white, or lilac, light purple, or lavender, or pale blue
It has 2 pairs of petals, 3 large sepals (outer petals), known as the 'falls' and 3 inner, smaller petals (or tepals), known as the 'standards. The falls are obovate, 4-5 cm long and 2.5 cm wide. They blue lines and yellow-brown (or purple, or mauve) spots around a large yellow or orange crest. The falls have wavy and serrated or denticulate (toothed edge or margins).The standards reflexed obliquely, oblanceolate to oblong, and 2.5-3 cm long and 1.5 cm wide. It has a furrowed apex.
It has a white 1 cm long perianth tube,8-9 mm long anthers, that are oblong to linear in shape, 1.5 cm long white filaments and a 1 cm long ovary.
It has pale blue or white style branches, that are 2 cm long and 6-7 mm wide, that has a fimbriae (fringed) lobe.
It is self-sterile
After the iris has flowered, it produces an oblong-ovate seed capsule, measuring 3-4 cm long It has the remains of the perianth tube on the apex of the capsule.
Distribution and Habitat
Iris formosana is native to temperate regions of Asia.
Range
It is found in north eastern Taiwan.
Habitat
It grows at forest margins, on hillsides or steep cliffs and beside roadsides.
It grows at mid-elevation and low-elevation Mountain, altitudes of between 500 to 1,000 m (1,600 to 3,300 ft.) above sea level.
Conservation
It is increasingly becoming scarce in the wild
The habitat of Iris formosana, is threatened by various factors including, climate change, and human influences. Examples of loss of habitat include a roadside being mowed regularly and sprayed with herbicide, and mudslides caused by torrential rains collapsing mountainous crags.