Plants Found On The KahukuCoastline

By Ken (Kenji) Suzuki, 2016

This booklet was designed as a very simplified guideto identify some of the beach plants found along the Kahukushoreline. Included are some introduced and native plants. A native plant is one that was growing here before thearrival of humans. Introduced plants were brought here bypeople, either accidentally or on purpose. It is gettingharder to find native plants along Oahu’s coastline, becauseof the impact that humans and animals have made on coastalareas.

The best way to learn about Oahu’s native coastalplants, is to go hiking with someone who can point them outto you. The Hawai`i Nature Center has guided hikes withan emphasis on our natural surroundings.

One of the best places to learn about the nativecoastal plants on O`ahu is the area around Kahuku. Thisarea is located from the Kahuku Golf Course to the TurtleBay Hotel.

A good source to learn about shoreline plants is MarkMerlin’s, Hawaiian Coastal Plants.

Sources used for information and graphics:Warren L. Wagner, Derral R. Herbst, S.H. Sohmer, Manual of the Flowering Plantsof Hawai`i, University of Hawai`i and Bishop Museum Press, 1990; Marie C. Neal,In Gardens of Hawai`i, Bishop Museum Press, 1965; Mark David Merlin, HawaiianCoastal Plants, Oriental Publishing Co., 1986; Dr. W. Arthur Whistler, WaysidePlants of the Islands, Isle Botanica; Dr. W. Arthur Whistler, Flowers of the PacificIsland Seashore, Isle Botanica; Dr. W. Arthur Whistler, Polynesian HerbalMedicine, National Tropical Botanical Garden, 1992; Roger E. Baldwin, Hawai`i’sPoisonous Plants, The Petroglyph Press, 1979; Edward Arrigoni, A Nature Walk toKa`ena Point, Topgallant Publishing Co. Ltd., 1978; Elbert Little and RogerSkolmen, Common Forest Trees of Hawai`i, United States Department ofAgriculture, 1989; Robert Hirano, Handbook of Hawaiian Weeds, University ofHawai`i Press, 1983; personal photos and other sources.

GLOSSARYNATIVE: A plant that has arrived in Hawai`i without

the help of humans. These plants camehere on the wind, in or on a bird, floatingor rafting on the ocean. The two types ofnative plants are:

INDIGENOUS: A plant that is found naturallyin other parts of the world.

ENDEMIC: A plant that is found only inHawai`i.

INTRODUCED: A plant that has been introduced byhumans either intentionally oraccidentally after Captain James Cooklanded on Kaua`i, on Jan. 20, 1778. Plants introduced by Hawaiians beforethis date are called Polynesianintroductions.

INDEX

1. Aki`aki2. `Akoko3. `Âkulikuli4. Alena5. Australian Saltbush6. Chinese Violet7. Golden Crown Beard8. Hinahina Kahakai9. Indian Pluchea10. Ironwood11. Milo

12. Nanea13. Naupaka Kahakai14. New Zealand Spinach15. `Ôhelo Kai16. Pâ`u O Hi`iaka17. Pôhuehue18. Spanish Needle19. Tree Heliotrope20. `Uhaloa

AKI`AKISEASHORE RUSHGRASS

(Sporobolus virginicus)

Grass family (Poaceae)Native: Indigenous to Hawai`i, tropical and subtropical areasworldwide

`Aki`aki is a hardy native grass that grows well in sandy,salty conditions. It is usually found above the high watermark and is common on the undeveloped beaches of O`ahu.`Aki`aki is well suited for lawns with sandy soils, exposedto salt spray.

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`AKOKO(Chamaesyce degeneri)

Spurge family (Euphorbiaceae)Native: Endemic to the Hawaiian Islands

There are about ten different kinds of `akoko that arenative to O`ahu. Some species of `akoko are found only onor near the coastline while others are found only on the wetsummits. The native coastal ̀ akoko (Chamaesyce degeneri)is rare on most of the coastline of O`ahu, but it can be foundalong the Kahuku coastline where it is common. Its leaves,like the other species of ̀ akoko, will bleed a white sap whenit is bent in half.

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`ÂKULIKULISEA PURSLANE

(Sesuvium portulacastrum)

Iceplant family (Aizoaceae)Native: Indigenous to Hawai`i and tropical regions of theworld

`Âkulikuli and ̀ ôhelo kai are very similar looking plants,but look at their stems to tell them apart. `Âkulikuli hassucculent stems, while `ôhelo kai has woody stems. It ishighly salt tolerant and has white to magenta, five-partedflowers. No significant uses have been reported for thisplant, but it has been said to be edible.

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ALENA(Boerhavia glabrata)

Four-o’clock family (Nyctaginaceae)Native: Indigenous to Hawai`i, southern and western Pacific

There several types of alena that are found on O`ahu. The most common native alena is pictured above. The rootsof certain types of native alena were used medicinally by

ancient Hawaiians.

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AUSTRALIAN SALTBUSH(Atriplex semibaccata)

Goosefoot family (Chenopodiaceae)Introduced: Native to Australia

Australian saltbush was probably introduced to Lâna`i in1895 as an experimental forage plant for cattle. It furnishesnourishing food for livestock as it is rich in protein. Tinyred fruits can be used as an aid to identify this plant. Theleaves have a salty taste, hence the common name saltbush.

Since its introduction in 1895, it has spread throughoutHawai`i and has become a serious weed in some coastalareas. One of the areas is in the Ka`ena Point natural areareserve, where work is currently being done to control thisweed which can crowd out our native plants.

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CHINESE VIOLET (Asystasia gangetica)

Acanthus family (Acanthaceae)Introduced: Native to India, Malay Peninsula and Africa

Chinese violet was first collected on O`ahu in 1925. It isgrown as a ground cover in tropical and subtropical regions. Chinese violet has escaped from cultivation on O`ahu and isnow common in low elevation, disturbed areas.

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GOLDEN CROWN BEARD (Verbesina encelioides)

Daisy family (Asteraceae)Introduced: Native to Mexico and southwestern UnitedStates

This plant was growing wild in Hawai`i prior to 1871. Itis most noticeable when in bloom, with attractive yellowflowers. No uses have been reported for this commonshoreline plant, but it is now considered an invasive speciesand steps are being taken to control it.

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HINAHINA KAHAKAI(Heliotropium anomalum variety argenteum)

Borage family (Boraginaceae)Native: This variety (argenteum) is endemic to the HawaiianIslands

Hinahina means silver or gray colored. Hawaiians named many plants hinahina, because they had silver or graycolored leaves. The beach hinahina or hinahina kahakai isthe flower of Kahoolawe where it grew profusely on the dryregions of that island. Its fragrant flowers and leaves areused in lei making. Also, hinahina kahakai was dried andused as a tea.

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INDIAN PLUCHEA (Pluchea indica)

Daisy family (Asteraceae)Introduced: Native to Southern Asia

Indian pluchea was first collected on O`ahu in 1915 andis now a common weedy shrub in dry, coastal areas. Thisplant is used medicinally in other parts of the world,internally to treat fevers, and externally as a poultice. Theyoung leaves are used to color and flavor food.

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IRONWOOD (Casuarina equisetifolia)

She-oak family (Casuarinaceae)Introduced: Native to Australia

This fast growing tree was first introduced to Hawai`i in1882 by Paul Isenburg, who planted it at Kilohana, Kauai.In 1890, Archibald Cleghorn, father of Princess Kaiulani,planted the impressive double row of trees, in what is nowknown as Kapi`olani park. Ironwood was extensively usedin forestry plantings from about 1919. Ironwood has hardwood and has been used on other Pacific Islands to makeweapons, canoe parts, house posts, tool handles and otheritems. Parts of the ironwood have also been usedmedicinally.

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MILO (Thespesia populnea)

Hibiscus family (Malvaceae)Native: Indigenous to Hawai`i and tropical regions

Milo has beautiful brown, hard wood which was used tomake calabashes, platters and dishes. Look for the roundgolf ball sized fruits as an aid in identifying this plant. Thebast was occasionally made into kapa and it seeds wereformerly used as a laxative. Milo is currently used inlandscaping.

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NANEA OR MOHIHIHIBEACH PEA

(Vigna marina)

Pea family (Fabaceae)Native: Indigenous to Hawai`i tropical coastal regions

There are no recorded uses of nanea or beach pea inancient Hawai`i. It is a hardy plant with attractive yellowflowers and it is now used as an ornamental ground coverin coastal sites.

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NAUPAKA KAHAKAIBEACH NAUPAKA

(Scaevola sericea)

Naupaka family (Goodeniaceae)Native: Indigenous to Hawai`i, tropical and subtropicalPacific & Indian Ocean coastlines

Naupaka kahakai is a shrub that can grow to heights ofabout 10 feet. It can withstand heat, drought and salt spray,but its roots can be easily injured by off road vehicles orhikers. Naupaka kahakai is a very important plant in thecoastal ecosystem. This plant binds the sand, holdsmoisture in the ground, provides shelter for other plants andhelps to make soil. The small, buoyant, marble sized fruitsare edible but not tasty. Naupaka kahakai is most noted forits “half” flowers, which along with naupaka kuahiwi(mountain naupaka) are inspiration for many legends.

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NEW ZEALAND SPINACH (Tetragonia tetragonioides)

Iceplant family (Aizoaceae)Introduced: Native to New Zealand

New Zealand spinach is sometimes cultivated and eatenas a vegetable. It has escaped from cultivation and is foundalong coastal areas on O`ahu. As it’s name implies, it issimilar to spinach in taste, texture, and nutrition. Likespinach, it contains oxalates which need to be removed byblanching the leaves in hot water for two or three minutes,then rinsing in cold water before cooking.

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`ÔHELO KAI (Lycium sandwicensis)

Tomato family (Solanaceae)Native: Indigenous to Hawai`i and Polynesia, ranging fromTonga to Easter Island

`Ôhelo kai looks like`âkulikuli, but look at their stems totell them apart. ̀ Âkulikuli has succulent stems while ̀ ôhelokai has woody stems. There have been few recorded usesfor this uncommon plant except that it has edible redberries.

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PÂ`Û O HÎ`IAKA (Jacquemontia ovalifolia subsp. sandwicensis)

Morning glory family (Convolvulaceae)Native: Subspecies (sandwicensis) is endemic to theHawaiian Islands

No significant uses have been reported for this beachplant. In Hawaiian legend, Hi`iaka was the sister of Pele,the volcano goddess. This plant had grown over Hi`iaka toshade her from the sun when Pele went on a fishing trip. Pele thus gave the name of pa`û o H`î`iaka or skirt ofHi`iaka to this plant.

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PÔHUEHUEBEACH MORNING GLORY

(Ipomoea pes-caprae subsp. brasiliensis)

Morning glory family (Convolvulaceae)Native: Indigenous to Hawai`i and tropical areas of theworld

Pôhuehue is common on undeveloped beaches of O`ahu.The roots and leaves were eaten in time of famine, butpurgative properties make it dangerous to eat.

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SPANISH NEEDLE OR KÎ NEHE(Bidens alba)

Sunflower or daisy family (Asteraceae)Introduced: Native to tropical America

There are several species of Spanish needle that havebeen introduced to Hawai`i. It is similar in appearance tothe native plant called ko`oko`olau. Spanish needle haswhite flowers which distinguish it from the yellow floweredko`oko`olau. It also has black barbed “stickers” whichcling to your clothes. In modern times, the leaves of theSpanish needle have been used medicinally, as a substitutefor ko`oko`lau.

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TREE HELIOTROPE(Tournefortia argentea)

Borage family (Boraginaceae)Introduced: Native to tropical Asia

Tree heliotrope is a recent introduction to Hawai`i and isnow common along Oahu`s shorelines. It is a small treeand not good for timber, but the wood is used in other partsof the world. Tree heliotrope is used to make canoe bailers,tool handles, gongs and carved handicrafts. Parts of the treeare used medicinally and the leaves are used to make a reddye.

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`UHALOA (Waltheria indica)

Cacao family (Sterculiaceae)Native: Indigenous to perhaps Hawai`i and to tropicalregions of the world

A common weed, `uhaloa is one of the best knownmedicinal plants in Hawai`i. The bark of the root is chewedthen gargled or swallowed to treat sore throats, asthma,coughs and colds.

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