Sagittaria longiloba
Encyclopedia
Sagittaria longiloba is a species of flowering plant in the water plantain family
known by the common name longbarb arrowhead and Gregg arrowhead. It is native to the southwestern United States and parts of Mexico and Nicaragua, where it grows in slow-moving, stagnant, and ephemeral water bodies such as ponds and small streams, and sometimes disturbed and cultivated habitat such as rice fields
and irrigation ditches
. It is a perennial aquatic plant
growing from a spherical tuber
. The leaves are sagittate, or shaped like arrowhead
s with two longer, narrower, pointed lobes opposite the shorter tip. The leaf blades are borne on very long petioles
. The plant is monoecious
, with individuals bearing both male and female flowers. The inflorescence
which rises above the surface of the water is a raceme
made up of several whorls of flowers, the lowest node bearing female flowers and upper nodes bearing male flowers. The flower is up to 3 centimeters wide with three white petals. The male flowers have rings of stamen
s at the centers. Female flowers each have a spherical cluster of pistils
which develops into a head of tiny fruits.
Alismataceae
The water-plantains are a family of flowering plants, comprising 11 genera and between 85-95 species. The family has a cosmopolitan distribution, with the greatest number of species in temperate regions of the Northern Hemisphere...
known by the common name longbarb arrowhead and Gregg arrowhead. It is native to the southwestern United States and parts of Mexico and Nicaragua, where it grows in slow-moving, stagnant, and ephemeral water bodies such as ponds and small streams, and sometimes disturbed and cultivated habitat such as rice fields
Paddy field
A paddy field is a flooded parcel of arable land used for growing rice and other semiaquatic crops. Paddy fields are a typical feature of rice farming in east, south and southeast Asia. Paddies can be built into steep hillsides as terraces and adjacent to depressed or steeply sloped features such...
and irrigation ditches
Irrigation
Irrigation may be defined as the science of artificial application of water to the land or soil. It is used to assist in the growing of agricultural crops, maintenance of landscapes, and revegetation of disturbed soils in dry areas and during periods of inadequate rainfall...
. It is a perennial aquatic plant
Aquatic plant
Aquatic plants are plants that have adapted to living in aquatic environments. They are also referred to as hydrophytes or aquatic macrophytes. These plants require special adaptations for living submerged in water, or at the water's surface. Aquatic plants can only grow in water or in soil that is...
growing from a spherical tuber
Tuber
Tubers are various types of modified plant structures that are enlarged to store nutrients. They are used by plants to survive the winter or dry months and provide energy and nutrients for regrowth during the next growing season and they are a means of asexual reproduction...
. The leaves are sagittate, or shaped like arrowhead
Arrowhead
An arrowhead is a tip, usually sharpened, added to an arrow to make it more deadly or to fulfill some special purpose. Historically arrowheads were made of stone and of organic materials; as human civilization progressed other materials were used...
s with two longer, narrower, pointed lobes opposite the shorter tip. The leaf blades are borne on very long petioles
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...
. The plant is monoecious
Plant sexuality
Plant sexuality covers the wide variety of sexual reproduction systems found across the plant kingdom. This article describes morphological aspects of sexual reproduction of plants....
, with individuals bearing both male and female flowers. The 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...
which rises above the surface of the water is a raceme
Raceme
A raceme is a type of inflorescence that is unbranched and indeterminate and bears pedicellate flowers — flowers having short floral stalks called pedicels — along the axis. In botany, axis means a shoot, in this case one bearing the flowers. In a raceme, the oldest flowers are borne...
made up of several whorls of flowers, the lowest node bearing female flowers and upper nodes bearing male flowers. The flower is up to 3 centimeters wide with three white petals. The male flowers have rings of stamen
Stamen
The stamen is the pollen producing reproductive organ of a flower...
s at the centers. Female flowers each have a spherical cluster of pistils
Gynoecium
Gynoecium is most commonly used as a collective term for all carpels in a flower. A carpel is the ovule and seed producing reproductive organ in flowering plants. Carpels are derived from ovule-bearing leaves which evolved to form a closed structure containing the ovules...
which develops into a head of tiny fruits.