Cyperus trachysanthos
Genus
Cyperus
Species
trachysanthos
Hawaiian Names with Diacritics
- Kaʻa
- Puʻukaʻa (Niʻihau)
Hawaiian Names
- Kaa
- Puukaa (Niihau)
Common Names
- Sticky flatsedge
- Sticky galingale
Synonyms
- Cyperus trachysanthus
Names with Unknown Sources
- Puʻu kaʻa
Distribution Status
Endemic
Endangered Species Status
Federally Listed
Plant Form / Growth Habit
- Non-Woody, Clumping
Mature Size, Height (in feet)
- Grass-like, Medium, 1 to 2.5
Mature Size, Width
Puʻukaʻa has a spread up to 12 inches.
Life Span
Long lived (Greater than 5 years)
Landscape Uses
- Accent
- Container
- Ground Cover
- Specimen Plant
- Water Features
Additional Landscape Use Information
Puʻukaʻa can be used as a specimen plant or en masse. This handsome native sedge is an excellent alternative choice for the non-native and greatly over used umbrella sedge (Cyperus alternifolius).
Puʻukaʻa is non-invasive and a beautiful addition to Japanese-style gardens, especially when surrounded by river rock or black cinder.
Plant Produces Flowers
Yes
Flower Type
Not Showy
Flower Colors
- Brownish
- Yellow
Additional Flower Color Information
Puʻukaʻa has 8 to 20 pale yellowish-brown to pale reddish-brown flowers. [1]
Blooming Period
- Year Round
Additional Blooming Period and Fruiting Information
These rare sedges are perennials.
Plant texture
- Coarse
Additional Plant Texture Information
Puʻukaʻa leaves range from 6 to over 18 inches long. Leaves are leathery and covered with a waxy, sticky coating. The degree of stickiness is apparently influenced by the heat; those growing in more sheltered, hotter locations seem stickier than those growing elsewhere. [1] The leaves are remotely toothed and not as sharp as some other native sedges.
Leaf Colors
- Medium Green
Additional Pest & Disease Information
Puʻukaʻa is prone to ants, scale, mealy bugs, root mealy bugs and aphids.
Fertilizer
Puʻukaʻa are not heavy feeders. Use well rotted compost or a weak application of soluble or organic fertilizers once a year.
A light foliar feeding with fish or kelp emulsion at one-third to one-fourth the recommended strength monthly or every other month produces good results. [David Eickhoff, Native Plants Hawaiʻi]
Water Requirements
- Wet
Additional Water Information
Plants can tolerate both moist and wet conditions. Puʻukaʻa can also be planted directly in the water or in areas with periodic flooding. [David Eickhoff, Native Plants Hawaiʻi]
Soil must be well drained
No
Light Conditions
- Full sun
- Partial sun
Additional Lighting Information
Puʻukaʻa can tolerate some shading but will not grow to its full potential.
Spacing Information
Plants should be spaced 12 to 18 inches apart.
Tolerances
- Waterlogged Soil
- Drought
- Salt Spray
Soils
- Clay
- Sand
Limitations
Puʻukaʻa does not do well in extremely windy areas because the leaves dry out and make the plant less attractive.
Natural Range
- Niʻihau
- Kauaʻi
- Oʻahu
- Molokaʻi
- Lānaʻi
Natural Zones (Elevation in feet, Rainfall in inches)
- Less than 150, Greater than 100 (Wet)
- 150 to 1000, Greater than 100 (Wet)
Habitat
- Terrestrial
Additional Habitat Information
Puʻukaʻa is known to grow in wet sites such as margins of ponds, wet slopes, mud flats, or wet clay soil. [2] Plants are found in dry regions in locations that are moist to flooded at least during the winter wet season. [Joel Lau, Botanist]
It is now found only on Kauaʻi, Oʻahu and possibly Niʻihau (Mokouia Valley).
Special Features and Information
General Information
There are fourteen species in the genus Cyperus that are native to the Hawaiian Archipelago, with eight that are endemic, or found exclusively, here. Cyperus belong to the Sedge Family (Cyperaceae) consisting of some 4,000 species in about 70 genera.
Famous, or infamous, non-native relatives include papyrus (Cyperus papyrus), the source of the Egyptian writing material and the origin of the English word paper; piripiri or cañita (Cyperus giganteus) used in parts of Mexico for plaiting sleeping mats and sambreros; and the ever-present noxtious lawn weed nutsedge or "nutgrass" (Cyperus rotundus) that keep homeowners busy and gardeners employed, but also used in Kampō (traditional Japanese/Chinese medicine). [4]
Etymology
The generic name Cyperus comes from the kyperos, the Greek word for sedge.
The specific epithet trachysanthos is from the Greek trachy, shaggy or rough, and santhos, flowered.
Hawaiian Names:
Puʻukaʻa is a Niʻihau name and the one used most locally. This Hawaiian name is also used for the Fragrant flatsedge (Cyperus odoratus [syn. Torulinium odoratum subsp. auriculatum]), a rare indigenous sedge found in the Hawaiian Islands.
Another seldom used name is Kaʻa. [3]
Background Information
Of the fourteen species of native sedges in the genus Cyperus, puʻukaʻa is certainly one of the rarest and is federally listed as an endangered species.
Early Hawaiian Use
Medicinally, this sedge was "stewed until completely cooked." Then, used in bathing "until the very small and fine lumps (puʻu) fall off." [5]
Modern Use
The attractive flowering spikes can be used in cut flower arrangements [Linda Bard, Waimea Valley].
They can also be used in haku or wiliwili style lei. [Rick Barboza, Hui Kū Maoli Ola]
Additional References
[1] "Flora Hawaiiensis" by Otto Degener, Family 48: Cyperus Trachysanthus
[2] "Recovery Plan for the Muli-Island Plants" by USFWS, pages 67, 68.
[3] "A Chronicle and Flora of Niihau" by Juliet Rice Wichman and Harold St. John, page 68.
[4] http://en.wikipedia.org/wiki/Cyperus [accessed 10/12/09]
[5] "Native Hawaiian Medicine--Volume III" by The Rev. Kaluna M. Kaʻaiakamanu, page 90.
PHOTOS FOR THIS SPECIES CAN BE SEEN AT THE LINK (Copy & Paste to your browser):
https://www.flickr.com/search/?user_id=50823119%40N08&sort=date-taken-desc&view_all=1&text=Cyperus%20trachysanthos
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