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19-536: Sisyrinchium bermudiana , known as Bermudiana or, along with other members of the genus, as blue-eyed grass , is a flower of the genus Sisyrinchium (of the iris family ) that is native to the Atlantic archipelago , and British Overseas Territory , of Bermuda and the island of Ireland . The plant appears and blooms in the spring. It has been used as a totemic flower by Bermudians, and appears in art, jewellery, banknotes and elsewhere. Sisyrinchium bermudiana

38-463: A rhizome , though some are short-lived (e.g. Sisyrinchium striatum ) , and some are annuals (e.g. Sisyrinchium iridifolium ). The flowers are relatively simple and often grow in clusters. Many species, particularly the South American ones, are not blue, despite the common name. The genus includes species with blue, white, yellow, and purple petals, often with a contrasting centre. Of

57-473: A corm forms from dead petiole sheaths—remnants of leaves produced in previous years. They act as a covering, protecting the corm from insects, digging animals, flooding, and water loss. The tunics of some species are thin, dry, and papery, at least in young plants, however, in some families, such as Iridaceae , the tunic of a mature corm can be formidable protection. For example, some of the larger species of Watsonia accumulate thick, rot-resistant tunics over

76-410: A period of years, producing a structure of tough, reticulated fibre. Other species, such as many in the genus Lapeirousia , have tunics of hard, woody layers. Internally, a typical corm mostly consists of parenchyma cells, rich in starch, above a circular basal node from which roots grow. Long-lived cormous plants vary in their long-term development. Some regularly replace their older corms with

95-401: A result, a corm cut in half appears solid inside, but a true bulb cut in half reveals that it is made up of layers. Corms are structurally plant stems, with nodes and internodes with buds and produce adventitious roots. On the top of the corm, one or a few buds grow into shoots that produce normal leaves and flowers. Corms can form many small cormlets called cormels , from the basal areas of

114-469: A stack of younger corms, increased more or less seasonally. By splitting such a stack before the older corm generations wither too badly, the horticulturist can exploit the individual corms for propagation. Other species seldom do anything of that kind; their corms simply grow larger in most seasons. Yet others split when multiple buds or stolons on a large corm sprout independently, forming a tussock. Corms can be dug up and used to propagate or redistribute

133-519: Is the Greek word, recorded by Pliny and Theophrastus , for the Barbary nut iris ( Iris or Moraea sisyrinchium ), and refers to the way the corm tunics resemble a shaggy goat 's-hair coat, sisýra . Authors as early as 1666 give the dubious etymology of Latin sūs "pig" and Greek rhynchos "nose", referring to pigs grubbing the roots. As Goldblatt and Manning explain, "the reason for applying

152-473: Is to use lower-case for all epithets. This Iridaceae article is a stub . You can help Misplaced Pages by expanding it . Sisyrinchium Sisyrinchium is a large genus of annual to perennial flowering plants in the family Iridaceae . Native to the New World , the species are known as blue-eyed grasses. Although they are not true grasses (Poaceae), they are monocots . Several species in

171-411: The basal area at the bottom of the corm. The second type are thicker layered roots called contractile roots that form as the new corms are growing. They pull the corm deeper into the soil. In some species contractile roots are produced in response to fluctuating soil temperatures and light levels. In such species, once the corm is deep enough within the soil where the temperature is more uniform and there

190-508: The eastern United States are threatened or endangered. This may be due to niche species emerging from their unique tendency toward rapid speciation which helps them adapt to specialized arenic habitats. These are not true grasses , but many species have the general appearance of grasses, as they are low-growing plants with long, thin leaves. They often grow on grasslands . Many species resemble irises , to which they are more closely related. Most species grow as perennial plants , from

209-451: The name to a genus of New World Iridaceae was apparently arbitrary." There are up to 200 species, including: Corm The word cormous usually means plants that grow from corms, parallel to the terms tuberous and bulbous to describe plants growing from tubers and bulbs . A corm consists of one or more internodes with at least one growing point, generally with protective leaves modified into skins or tunics . The tunic of

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228-404: The new growing corms, especially when the main growing point is damaged. These propagate corm-forming plants. A number of species replace corms every year by growing a new corm. This process starts after the shoot develops fully expanded leaves. The new corm forms at the shoot base just above the old corm. As the new corm grows, short stolons appear that end with the newly growing small cormels. As

247-406: The ones that produce cormels in the greatest numbers and most widely distributed over the plant. Homeria species produce bunches of cormels on underground stem nodes, and Watsonia meriana for example actually produces cormels profusely from under bracts on the inflorescences . Those growing from the bottom of the corm are normal fibrous roots formed as the shoots grow, and are produced from

266-546: The plant (see, for example, taro ). Plants with corms generally can be propagated by cutting the corms into sections and replanting. Suitably treated, each section with at least one bud usually can generate a new corm. Corms are sometimes confused with true bulbs ; they are often similar in appearance to bulbs externally, and thus erroneously called bulbs. Corms are stems that are internally structured with solid tissues, which distinguishes them from bulbs, which are mostly made up of layered fleshy scales that are modified leaves. As

285-399: The plants grow and flower, they use up the old corm, which shrivels away. The new corm that replaces the old corm grows in size, especially after flowering ends. The old corm produces the greatest number of cormels when close to the soil surface. Small cormels normally take one or two more years of growth before they are large enough to flower. Cormels do have a reproductive function, but in

304-469: The relationships between the species. Some species, notably Sisyrinchium douglasii , have been transferred to the separate genus Olsynium . The greatest diversity for the genus is found in South America. Approximately one third of the species in the genus have oil producing hairs called elaiophores to attract oil-bees. Nearly all these species are native to South America. Sisyrinchíon

323-833: The species in the United States, the Western Blue-eyed Grass (Sisyrinchium bellum ) is sometimes found with white flowers, while the California Golden-eyed Grass ( Sisyrinchium californicum ) has yellow flowers. The genus was named by Carl Linnaeus in 1753, based on the species Sisyrinchium bermudiana (commonly called Bermudiana ). The taxonomy of this genus is rather perplexing and confusing, as several of these species, such as Sisyrinchium angustifolium , form complexes with many variants named as species. More genetic research and cladistic analysis need to be performed to sort out

342-484: The wild they also are important as a survival strategy. In most places where geophytes are common, so are animals that feed on them, whether from above like pigs, or from below like bulb weevils, mole rats , or pocket gophers . Such animals eat through protective tunics, but they generally miss several cormels that remain in the soil to replace the consumed plant. Plants such as Homeria , Watsonia and Gladiolus , genera that are vulnerable to such animals, are probably

361-401: Was first described by Carl Linnaeus in 1753. The first described species in the genus Sisyrinchium , it is thus the type species . Linnaeus's specific epithet bermudiana was not an adjective (and thus does not have to agree in gender with Sisyrinchium ) but a noun in apposition, derived from the earlier genus name Bermudiana . He showed this by capitalizing the epithet, but modern practice

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