Native Plants of Hawai‘i - Schoenoplectus tabernaemontani

Schoenoplectus tabernaemontani

Cyperaceae or Sedge family

Synonyms: Schoenoplectus lacustris, Schoenoplectus lacustris subsp. creber, Schoenoplectus lacustris subsp. glaucus, Schoenoplectus lacustris subsp. tabernaemontani, Schoenoplectus lacustris subsp. validus, Schoenoplectus validus, Schoenoplectus validus var. creber, Schoenoplectus validus subsp. luxurians, Scirpus glaucus, Scirpus lacustris, Scirpus lacustris subsp. glaucus, Scirpus lacustris f. luxurians, Scirpus lacustris var. luxurians, Scirpus lacustris subsp. tabernaemontani, Scirpus lacustris var. tabernaemontani, Scirpus lacustris subsp. validus, Scirpus lacustris var. validus, Scirpus tabernaemontani, Scirpus tabernaemontani f. luxurians, Scirpus validus, Scirpus validus subsp. creber, Scirpus validus var. creber, Scirpus wahuensis

ʻAkaʻakai

ʻAkaʻakai naku, Kaluhā, Naku, Nānaku, Neki

Common club-rush, Giant bulrush, Great bulrush, Greater bulrush, Grey club-rush, Lakeshore bulrush, Soft-stemmed bulrush, Tule

Natural Range & Environment

Widely distributed in north temperate regions and on tropical high mountains of North and South America, Pacific islands, Australia, Malesia, and southern AsiaIn the Hawaiian Islands, indigenous to Ni`ihau, Kaua`i, O`ahu, Moloka`i, Maui, Hawai`i.

HI exc. L, Ka

ʻAkaʻakai occurs in fresh, brackish and salt water marshes from sea level to 4,000 feet.

ʻAkaʻakai provides an excellent natural component in Hawaiian wetlands for native and migratory waterfowl who use them for food, shelter, and nesting material.

ʻAkaʻakai produces tassels of small flowers atop their stems that mature into ovoid brown achenes when pollinated (achenes photograph courtesy of Robert L. Carr ©). It spreads via robust rhizomes with new stems emerging every couple of inches (photograph courtesy of Stefan.lefnaer CC BY-SA 4.0). The stems of ʻakaʻakai have many air cavities, which make it compress easily when squeezed, hence one of its common names is soft-stemmed bulrush (photograph courtesy of User:Bb143143 CC BY-SA 3.0). ʻAkaʻakai has a wide geographic range. Here a cultivated plant grows in wet soil on Hawai‘i Island (photograph courtesy of J.B. Friday ©) as easily as this wild plant grows in the shallows of a lake in upstate New York, USA (photograph courtesy of Erik Danielsen CC BY-NC 4.0).

Description

Grass-like, Tall, Greater than or equal to 2.5

ʻAkaʻakai is known to spread up to 8 feet or more in width.

Long lived (Greater than 5 years)

The round stalks of this bulrush range from 8 to more than 10 feet tall and resemble the leaves of an onion when not in bloom. Inside the stalk is a light weight white pithy material called aerenchyma which, also found in water hyacinth, gives it buoyancy. [Angela Nishimoto, Leeward Community College]

Stalks are dull green.

Akaʻakai has numerous egg-shaped rusty brown spikelets.

Blooming Period

Year Round

This very tall sedge is a perennial.

Growth Requirements

General

Container

Ground Cover

Hedges

Screening

Water Features

The stalks are very tall and suitable as a screening or a free form hedge in water features.

Plant ʻakaʻakai in clumps of at least a foot wide to ensure there will be sufficient shoots (rhizomes) to spread out and form new stalks. Space clumps of plants at least 1 to 3 feet apart. They will grow together at a slow to moderate rate to form a dense mat. [David Eickhoff, Native Plants Hawaiʻi]

In containers that hold water, some fertilizer is appreciated but be cautious of too much nitrogen which can produce green algae in water. None necessary in large water features such as fish ponds. The plants will receive nutrient needs from the watery habitat it grows in. Never apply fertilizer in natural wetlands sites. [David Eickhoff, Native Plants Hawaiʻi]

Trim spent or bent over stalks in landscape settings.

ʻAkaʻakai is best grown directly in the water. But can be grown in very wet locations as well.

Soil must be well drained

Full sun is optimal but does grow with some shading if it has a few hours of full sun during at least part of the day. [David Eickhoff, Native Plants Hawaiʻi]

Tolerances

Waterlogged Soil

Brackish Water

Salt Spray

Heat

Soils

Clay

Sand

Organic

Needs to be grown in water with constant moisture.

Pests and Diseases

This rush is prone to ants, scale, mealy bugs and aphids.

Uses

Ancient Hawaiian

Never cultivated by early Hawaiians, but wild plants were used. [2]

They were also used as mulch. [6]

The stems were dried before plaiting. The stems were used whole or split. Then one or two of the lower layers of coarse mats (hikieʻe) were placed directly on the pebble floors over which the more precious lau hala mats were used to prevent them from wearing out. [1,2,3,5]

The leaves were also used for house thatching as they did with grass or ti (kī). [5]

Medicinally, the root was used with green kukui fruit and flowers, ripe noni fruit, and kō kea (white sugarcane) for treating ʻōpū ‘aki hikoko (severe stomach aches or intestinal ailments, and internal hemorrhaging). [6]

Modern

In the mid-1900's, truck farmers in the islands used these bulrushes as string to tie vegetables into bundles. [5]

Special Features and Information

General

The large Sedge family (Cyperaceae) has about 5,500 described species in approximately 90 genera [WikipediA;Cyperaceae]. There are currently (2025) fourteen Cyperus species native to Hawai‘i, nine being endemic, while the rest are indigenous. There are also about 25 non-native and naturalized Cyperus species in Hawai‘i [Flora of the Hawaiian Islands]. Some of the better-known non-native Cyperus species in Hawai‘i are: papyrus (Cyperus papyrus), the source of ancient Egyptian paper and the origin of the English word "paper"; umbrella sedge (Cyperus involucratus), a popular ornamental; and purple nutsedge or "nutgrass" (Cyperus rotundus), a noxious lawn weed that keep homeowners busy and commercial gardeners employed.

Hawaiian Name

Kahakai

Etymology

Schoenoplectus comes from the Ancient Greek words, skhoînos, meaning "reed," and and plektós, meaning "twisted" [Wiktionary], likely referring to how the stems are/were traditionally woven into mats, etc., by many indigenous peoples including Hawaiians.

The species name, tabernaemontani, honors Jacobus Theodorus known as Tabernaemontanus (born 1520–1525; died in 1590), a German physician, botanist, and herbalist. His Latinized name is a compressed form of Tabernae Montanae ("tavern in the mountains"), the Medieval name of his home town, Bergzabern [WikipediA].

Additional References

[1] Arts and Crafts of Hawaii" by Te Rangi Hiroa (Sir Peter H. Buck), pages 131-132.

[2] "Plants of the Canoe People" by W. Arthur Whistler, page 189.

[3] "Niihau--The Traditions of an Hawaiian Island" by Rerioterai Tava, page 34.

[4] "The Names of Plants" by David Gledhill, page 369.

[5] "In Gardens of Hawaii" by Marie C. Neal, pages 88-89.

[6] "Hawaiian Ethnobotany Online Database" http://data.bishopmuseum.org/ethnobotanydb [Accessed 1/29/13]

BPK