Arrowgrass

views updated Jun 08 2018

Arrowgrass

The arrowgrass family (Juncaginaceae) is a family of herbaceous plants whose grasslike leaves are shaped somewhat like an arrowhead. The arrowgrass family has four genera: Scheuchzeria with two species; Thrighlochin with 12 species; Maundia with one species; and Tetroncium with one species.

All arrowgrass species grow in wet or moist habitats in temperate and cold climates. Many grow in fresh water and are common in sphagnum bogs. Others grow in brackish (semi-salty) water. All plants in this family have thin, linear, grasslike leaves. They have a specialized underground stem or rhizome from which leaves and roots arise. The roots of some species are fat and tuberous. Most species are perennial, maintaining leaves all year round.

The flowers of all species are small and inconspicuous, with clusters arising from an erect stalk, an inflorescence known as a spike or raceme. The flowers are symmetrical, and the different parts of the flowers occur in threes or multiples of three. Some species have bisexual (monoecious) flowers, with male and female organs in the same flower. Others have unisexual (dioecious) flowers, with male and female organs in different, separate flowers. The flowers of all species are wind pollinated.

The fertilized flowers give rise to fruits, referred to as folliclesdry fruits that split along a suture on one side to release seeds. The follicles of arrowgrass plants have one or two seeds, each of which has one cotyledon (seed leaf).

The arrowgrass plants are not of great economic significance to humans. However, the leaves or rhizomes of some species have been food sources for some aboriginal peoples of North America and Australia.

Arrowgrass

views updated May 29 2018

Arrowgrass

The arrowgrass family (Juncaginaceae) is a family of herbaceous plants whose leaves are grass-like and shaped somewhat like an arrowhead. The arrowgrass family has four genera: Scheuchzeria with two species ; Thrighlochin with 12 species; Maundia with one species; and Tetroncium with one species.

All species in the arrowgrass family grow in wet or moist habitats in temperate and cold regions of the world. Many species grow in fresh water and are common in sphagnum bogs. Other species grow in brackish (semi-salty) water.

All plants in this family have thin, grass-like leaves that are flat, linear, and smooth. They have a specialized underground stem, referred to as a rhizome . The leaves and roots arise from the rhizome. The roots of some species are fat and tuberous. Most species are perennial, in that they maintain leaves all year round.

The flowers of all species are small and inconspicuous, with clusters of individual flowers arising from an erect stalk. This inflorescence is referred to as a spike or raceme. The flowers are symmetrical, and the different parts of the flowers occur in threes or in multiples of three. Some species have bisexual (monoecious) flowers, in that male and female organs occur on the same flower . Other species have unisexual (dioecious) flowers, with male and female organs occurring in different, separate flowers. The flowers of all species are wind-pollinated.

The fertilized flowers give rise to fruits , referred to as follicles. A follicle is a dry fruit that splits along a suture on one side to release the seed(s). The follicles of plants in the arrowgrass family have one or two seeds . Each embryonic seed has one cotyledon (seed leaf ).

The plants of the arrowgrass family are not of great economic significance to humans. However, the leaves or rhizomes of some species have been traditionally eaten by some aboriginal peoples of North America and Australia .

Juncaginaceae

views updated May 18 2018

Juncaginaceae A family of monocotyledonous (Monocotyledoneae) herbs most of which have linear, radical, sheathing leaves, and erect spikes or racemes of tiny di- or trimerous flowers without bracts. The ovary is superior, with 4 or 6 carpels, usually joined together, and a short style. Triglochin (arrow-grass) is widespread and occurs in wet places. There are 4 genera, with 18 species, distributed in temperate and cold, marshy habitats in the northern and southern hemispheres.