Iris brevicaulis is a species in the genus Iris, it is also in the subgenus Limniris and in the series Hexagonae. It is a rhizomatous perennial, from North America. It has bright green, glossy long leaves, a long zig-zagged stem and 3–6 flowers per stem, which are come in blue shades from violet-blue, to lavender, to purple-blue, to bright blue to blue, and pale blue.
Description
Iris brevicaulis is the smallest in all the Hexagonae series of Louisiana irises. Its leaves and stalks are much shorter than the other species. It is similar in form to Iris virginica, The flowers are normally never seen above the foliage, due to the short zig-zagging flower stems and occasionally, due to the habit of the stems to lie along the floor, or it is often decumbent (meaning the branches growing horizontally but turned up at the ends).
It has a shallowly rooted, branching rhizome (about 10–25 mm in diameter), that can eventually form large colonies of plants (2 x 3 ft wide).
It has long, glossy leaves, which are ensiform (sword-like), and grow from the base (of the plant). They are bright green, and grow to between long and broad.
It has a zig-zagged stem (known in botany as fractiflex; hence the common name of Zig-zag iris) going at approx. 45 degrees angles (to each other), which grows to between tall. It has about 3–6 flowers per stem, 1–2 flowers at each axil, and at the terminus of the stem.
It begins blooming in early to mid summer, from April to mid-July, or June (in the UK). Occasionally it does not produce flowers every year.
The flowers are produced in a range of blue shades, from violet-blue, to lavender, to purple-blue, to bright blue, to blue, and pale blue shades. There is occasionally a white flowered form. The large flowers are across, with horizontal falls (sepals) that arch downward and upright standards (petals). The petals are dark-veined and smaller than the sepals, which have a yellow (or whitish-yellow) signal patch or stripe. It has a yellow pubescence (rudimentary beard) on the sepals, (sometimes called falls).
It has green styles and pale lavender style crests (which are ovate in form), and short anthers.
It has a 6-angled seed capsule (similar to Iris hexagona), which is 3–5 cm long. Inside the irregular, circular seeds have a cork-like coating which allows them to float and thus aid in dispersal in its wet habitat.
Genetics
As most irises are diploid, having two sets of chromosomes. This can be used to identify hybrids and classification of groupings. It has a chromosome count of 2n=44. It has been counted many times, 2n=44-Simonet 1934, 2n=42 by Randolph 1958 and 2n=42, Randolph in 1966.
Taxonomy
It is pronounced as EYE-riss brev-ih-KAWL-iss.
It has several common names including 'Zig-zag iris', or short-stemmed iris, or 'Lamance iris', (especially in Tennessee), or 'Leafy Blue Flag', (especially in Ohio).
The name of 'Lamance iris' comes from 'Lora La Mance', an American horticulturalist and author (1857–1939). The 'Brevicaulis' epithet comes from the latin for 'short stem'.
It was first published and described by Constantine Samuel Rafinesque in 'Florula Ludoviciana', (Flora of the State of Louisiana) in 1817.
Michael Foster was the first botanist and author to realise that Iris brevicaulis Raf. had the same description as Iris foliosa MacKenzie & Bush (published in Trans. Acad. Sci. St. Louis 12: 80–81. in 1902). Later authors agreed with this assessment, including Brian Mathew (The Iris, 1981) and Clive Innes (The World of Iridaceae). But 'Iris foliosa' was used in the 1939 Checklist and 'Index Kewensis'. But most authors have agreed that Iris foliosa is a synonym.
It was verified by United States Department of Agriculture and the Agricultural Research Service on 4 April 2003, then updated on 2 December 2004, and it is an accepted name by the RHS.
Distribution and habitat
Iris brevicaulis is the hardiest and most adaptable of all the Louisiana irises. Occurring a wide range of habitats. It is native to North America.
Range
It is found in Ontario, Canada, up as far north as the north-east shore of Lake Erie. Also in many southeastern states of the United States, including Alabama (along various rivers,), Arkansas, Florida, Georgia, Illinois, Indiana, Kansas (Leavenworth,), Kentucky, Louisiana, Mississippi (around the Mississippi river basin,), Missouri, Ohio, Oklahoma, Tennessee and Texas. (including the Big Thicket forest).