Cyperus papyrus

Cyperus papyrus, better known by the common names papyrus, papyrus sedge, paper reed, Indian matting plant, or Nile grass, is a species of aquatic flowering plant belonging to the sedge family Cyperaceae. It is a tender herbaceous perennial, native to Africa, and forms tall stands of reed-like swamp vegetation in shallow water.

Papyrus sedge (and its close relatives) has a very long history of use by humans, notably by the Ancient Egyptians (as it is the source of papyrus paper, one of the first types of paper ever made). Parts of the plant can be eaten, and the highly buoyant stems can be made into boats. It is now often cultivated as an ornamental plant.

In nature, it grows in full sun, in flooded swamps, and on lake margins throughout Africa, Madagascar, and the Mediterranean countries. It has been introduced outside its range to tropical regions worldwide (such as the Indian subcontinent, South America, and the Caribbean).

Description
This tall, robust aquatic plant can grow 4 to 5 m high, but on the margins of high altitude lakes such as Lake Naivasha in Kenya and Lake Tana in Ethiopia, at altitudes around 6000 ft the papyrus culms can measure up to 29.5 ft in length, with an additional 18 in for the inflorescence (a spicate umbel; i.e. each of the up to one thousand rays of the umbel terminates in a spike of small flowers) for a total height of 31 ft. Each culm is a single internode —the longest known of any plant. At Lake Naivasha, the culms, triangular in cross-section, were as much as 7 in on a side in width. It forms a grass-like clump of triangular green stems that rise up from thick, woody rhizomes. Each stem is topped by a dense cluster of thin, bright green, thread-like rays around 10 to 30 cm in length, resembling a feather duster when the plant is young. Greenish-brown flower clusters eventually appear at the ends of the rays, giving way to brown, nut-like fruits.

Although no leaves are apparent above the soil line, the younger parts of the rhizome are covered by red-brown, papery, triangular scales, which also cover the base of the culms. Technically, these are reduced leaves, so strictly it is not quite correct to call this plant fully "leafless".

Papyrus in history
Egyptians used the plant (which they called aaru, or the subspecies C. p. papyrus, which came very close to extinction, but was rediscovered in 1968. ) for many purposes, including for making papyrus paper. Its name has an uncertain origin, but was rendered in Hellenistic Greek as πάπυρος.

In the Nile Delta, Cyperus papyrus was widely cultivated in ancient times. It is for example depicted on a restored stucco fragment from the palace of Amenhotep III near the present-day village of Malkata. Currently, only a small population remains in Egypt, in Wadi El Natrun. Theophrastus's History of Plants (Book iv. 10) states that it grew in Syria, and according to Pliny's Natural History, it was also a native plant of the Niger River and the Euphrates. Neither the explorer Peter Forsskål, an apostle of Carl Linnaeus, in the 18th century, nor the Napoleonic expedition saw it in the delta.

Aside from papyrus, several other members of the genus Cyperus may also have been involved in the multiple uses Egyptians found for the plant. Its flowering heads were linked to make garlands for the gods in gratitude. The pith of young shoots was eaten both cooked and raw. Its woody root made bowls and other utensils and was burned for fuel. From the stems were made reed boats (seen in bas-reliefs of the Fourth Dynasty showing men cutting papyrus to build a boat; similar boats are still made in southern Sudan), sails, mats, cloth, cordage, and sandals. Theophrastus states that King Antigonus made the rigging of his fleet of papyrus, an old practice illustrated by the ship's cable, wherewith the doors were fastened when Odysseus slew the suitors in his hall (Odyssey xxi. 390).

The "rush" or "reed" basket in which the Biblical figure Moses is supposed to have been placed may have been made from papyrus.

The adventurer Thor Heyerdahl had a boat built for him of papyrus, Ra, in an attempt to demonstrate that ancient African or Mediterranean people could have reached America. He was unsuccessful with this boat. Fishermen in the Okavango Delta use small sections of the stem as floats for their nets.

Ecology
Papyrus can be found in tropical rain forests, tolerating annual temperatures of 20 to 30 °C and a soil pH of 6.0 to 8.5. It flowers in late summer, and prefers full sun to partly shady conditions. Like most tropical plants, it is sensitive to frost. In the United States, it has become invasive in Florida and has escaped from cultivation in Louisiana, California, and Hawaii.

Papyrus sedge forms vast stands in swamps, shallow lakes, and along stream banks throughout the wetter parts of Africa, but it has become rare in the Nile Delta. In deeper waters, it is the chief constituent of the floating, tangled masses of vegetation known as sudd. It also occurs in Madagascar, and some Mediterranean areas such as Sicily and the Levant.

The "feather-duster" flowering heads make ideal nesting sites for many social species of birds. As in most sedges, pollination is by wind, not insects, and the mature fruits after release are distributed by water.

Papyrus is a C4 sedge that forms highly productive monotypic stands over large areas of wetland in Africa.

Cultivation
The papyrus plant is relatively easy to grow from seed, though in Egypt, it is more common to split the rootstock, and grows quite fast once established. Extremely moist soil or roots sunken in the water is preferred and the plant can flower all year long. Vegetative propagation is the suggested process of creating new plants. It is done by splitting the rhizomes into small groups and planting normally. It can reach heights of up to 16 feet tall. C. papyrus is considered to be hardy in USDA hardiness zones 9 and 10.

C. papyrus and the dwarf cultivar C. papyrus 'Nanus' have gained the Royal Horticultural Society's Award of Garden Merit (confirmed 2017).

Uses
In Ancient Egypt, papyrus was used for various of purposes such as baskets, sandals, blankets, medicine, incense, and boats. The woody root was used to make bowls and utensils, and was burned for fuel. The Papyrus Ebers refers to the use of soft papyrus tampons by Egyptian women in the 15th century BCE. Egyptians made efficient use of all parts of the plant. Papyrus was an important "gift of the Nile" which is still preserved and perpetuated in Egyptian culture.