Juncus is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 in the plant family Juncaceae

Juncaceae

Juncaceae, the rush family, are a monocotyledonous family of flowering plants. There are eight genera and about 400 species. Members of the Juncaceae are slow-growing, rhizomatous, herbaceous plants, and they may superficially resemble grasses. They often grow on infertile soils in a wide range...

. It consists of some 200 to 300 or more species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of grass

Grass

Grasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns ...

y plants commonly called rushes. They occur in all sorts of wetlands regions all over the world, but more rarely in the tropics

Tropics

The tropics is a region of the Earth surrounding the Equator. It is limited in latitude by the Tropic of Cancer in the northern hemisphere at approximately  N and the Tropic of Capricorn in the southern hemisphere at  S; these latitudes correspond to the axial tilt of the Earth...

.

Characteristics

Juncus rushes are characterized by their nude leaves, which are either thin and more or less flattened or round and containing spongy pith

Pith

Pith, or medulla, is a tissue in the stems of vascular plants. Pith is composed of soft, spongy parenchyma cells, which store and transport nutrients throughout the plant. In eudicots, pith is located in the center of the stem. In monocots, it extends also into flowering stems and roots...

. They grow as tussock

Tussock

Tussock most often refers to a small hillock of grassy, or grass-like plant growth, but may also refer to Plants and ecology, Insects.- Plants and ecology :*Tussock *New Zealand tussock grasslands*Serrated Tussock...

s or more isolated stalks, bearing inflorescence

Inflorescence

An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...

s near the tip. Many species are exceptionally hardy and some are considered weed

Weed

A weed in a general sense is a plant that is considered by the user of the term to be a nuisance, and normally applied to unwanted plants in human-controlled settings, especially farm fields and gardens, but also lawns, parks, woods, and other areas. More specifically, the term is often used to...

s in gardening

Gardening

Gardening is the practice of growing and cultivating plants. Ornamental plants are normally grown for their flowers, foliage, or overall appearance; useful plants are grown for consumption , for their dyes, or for medicinal or cosmetic use...

; a few are invasive weeds of significance. On the other hand, there is some use of rushes as ornamental plant

Ornamental plant

Ornamental plants are plants that are grown for decorative purposes in gardens and landscape design projects, as house plants, for cut flowers and specimen display...

s, e.g. at garden pond

Garden pond

A garden pond is a water feature constructed in a garden or designed landscape, normally for aesthetic purposes and/or to provide wildlife habitat.-Habitat:...

s; more generally their tolerance of extreme environmental conditions (except drought) means that some species or another is likely suitable for ornamental purposes even where few other plants grow. Additionally, Juncus species are used as food plants by the larva

Larva

A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...

e of certain Lepidoptera

Lepidoptera

Lepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...

 species.
Historically and in some regions still today, there is artisanal use of the leaves. Probably most widely known is the Soft Rush

Soft rush

Soft Rush is a member of the genus Juncus. Native to most continents and hence also known as Common Rush, this plant is found growing in wet areas, such as the purple moor-grass and rush pastures and fen-meadow plant associations in the United Kingdom.-Description:It grows in large clumps about...

 (Juncus effusus), called igusa in Japanese

Japanese language

is a language spoken by over 130 million people in Japan and in Japanese emigrant communities. It is a member of the Japonic language family, which has a number of proposed relationships with other languages, none of which has gained wide acceptance among historical linguists .Japanese is an...

 and used to weave the soft surface cover of tatami

Tatami

A is a type of mat used as a flooring material in traditional Japanese-style rooms. Traditionally made of rice straw to form the core , with a covering of woven soft rush straw, tatami are made in standard sizes, with the length exactly twice the width...

mats.

Selected species

Species of Juncus include: