| Pritchardia (pritch-AHR-dee-ah) |
Loulu or Nihoa fan palm Arecaceae Endemic to the Hawaiian Islands. Endangered, Oʻahu (Cultivated); Nīhoa form. Photo by Dr. David Eickhoff
Habitat and DistributionHawaii. Dry forest at the base of basalt cliffs, Nihoa "Bird Island", off the northwest
Pritchardia remota is one of the smallest in the genus, usually not more than 4–5 m tall (though taller individuals has been reported in cultivation in Hawaii). It distinguish from other Pritchardia species by its wavy leaves, its short and hairless inflorescences, and its tiny, spherical fruits. This species may be confused with Pritchardia hillebrandii but the crown of Pritchardia remota is more untidy and the leaves are much more deeply divided. Trunk: Solitary, up to 15 centimetres in diameter, slim, flexuous, ringed by leaf scars that are left after leaves have fallen. Crown: Dense and untidy looking due to the deeply divided leaves with drooping tips. Leaves: Leaf blades about 85 cm long, costapalmate, moderately plicate (folded like a fan from the base to the tips of the leaf), somewhat ruffled with drooping tips, split about 1/3 their length and nearly semicircular, smooth on the top surface, but slightly waxy and very lightly covered with tiny scales on the lower side. Petiole up to 1 m long. Inflorescence: Large, many branched, shorter than the petiole visible beneath the leaf crown. The flowers are arranged spirally along the branches. Fruit: Near spherical to ovoid, approximately 20 x 18 mm dark brown or black at maturity with only one seed. The fruit has tree layers: a shining outer skin (exocarp), a fibrous middle layer (mesocarp), and a hard inner endocarp. Seed: 13-15 mm in diameter. The seed is attached to the endocarp at one small spot called the hilum. (llifle.com)
Notes: Pritchardia remota complex is a group of similar species closely related owing to their recent and usually still incomplete reproductive isolation. The additional palms in the complex are: Pritchardia aylmer-robinsonii, Pritchardia glabrata, Pritchardia napaliensis and Pritchardia wailealeana. (llifle.com)
|Detailed Scientific Description|
To 10 m tall; proximal margins of petiole moderately fibrous; leaf blade strongly undulate, slightly waxy glaucous, divided 2/5-3/5, abaxial surface incompletely covered with scattered lepidia, segment tips drooping; inflorescences composed of 1-5 panicles, shorter than to equaling petioles in flower and fruit, panicles branched to 3 orders, rachillae glabrous; fruits 18-20 x 18 or 19 mm, globose. (Hodel, D. 2007)/Palmweb.
Nihoa pritchardia grows to only 4 to 5 m in height with a narrow trunk that is less than 15 cm in diameter. The trunk has leaf scars appearing as rings along its length that are left after leaves have fallen. The leaf blades of this species are about 85 cm long and are supported by a stalk or petiole that is up to 1 m long. The leaf blades are said to be plicate meaning they are folded like a fan from the base to the tips of the leaf. The flowers are borne in clusters that are visible beneath the leaf stalks. The clusters are densely branched and the flowers are arranged spirally along the branches. The fruit of Nihoa pritchardia are about 2 cm long and 1.8 cm wide and are greenish brown when mature with a shiny surface. (National Tropical Botanical Garden) Editing by edric.
Pritchardia remota is another of the four Hawaiian species, that are recorded from more than one island. It is difficult to distinguish from P. glabrata and P. waialealeana. All three share the undulate leaf blades incompletely covered abaxially with lepidia and with drooping segment tips, inflorescences shorter than or equaling the petioles with panicles branched to three orders, glabrous rachilJae, and small fruits. However P. glabrata differs in its leaf blades lacking the glaucous covering while P. waialealeana differs in the cottony hairs or mealy indumentum lacking on the abaxial folds of its leaf blades and the longerthan- wide fruits. Also, leaf blades of P. remota have a somewhat coarse and heavy-looking appearance. I am unable to find significant differences between Pritchardia remota and P. aylmer-robinsonii after examining the types and cultivated living plants from the type localities of both species. Some cultivated plants of P. remota have distinctive orange flowers yet photographs taken by Derral Herbst at the type locality on Nihoa show the flowers to be yellow. Beccari initially based Pritchardia remota on a portion of an inflorescence that Hillebrand had collected from a plant cultivated on the grounds of lolani Palace in Honolulu that a Dr. Rooke had procured from Nihoa Island in 1858. Beccari (Beccari & Rock 1921) later expanded the description from material that Brown had collected on Nihoa in 1911 and that Rock had forwarded to Beccari. There is another Hillebrand collection at K, which is complete and contains leaves and inflorescences, that Beccari may have also used to expand the description. (iucn.org)
According to its habitat Pritchardia remota may be drought tolerant, cool tolerant and modest in its requirement. Since it is the north most naturally occurring Pritchardia, it seems to be better adapted to Mediterranean-type climates than any other species in the genus.
Soil: Sand, cinder organic soil, but is adaptable. Good drainage is also important. Fertilization: Need a perfect fertilizer diet including all micro nutrients and trace elements or slow release fertilizer. Fertilize often for faster growth.
Water Requirements: It tolerates low levels of humidity, though it prefers evenly moist but not consistently wet medium. When supplied with adequate moisture and fertilizer it is also fairly fast growing. This palm is very drought tolerant once established. It dislikes soggy soils. The roots and lower trunk can rot if soil is kept too moist. Water young plants for healthy look and fastest growth.
Light: Prefers full sun but will tolerate half day sun. Hardiness: It is adapted to tropical and subtropical climates but tolerate a wide range of climates and will even tolerate cool conditions; In favourable temperate climate they should be grown in cold green houses or at least in a place where they are sheltered by the wind; However mature specimens can endure light frost (for short periods), while young plants are more cold sensitive. Best kept above 5° C. (USDA zones 10-11 but quite hardy in zone 9b).
Maintenance: The dead leaves, flowers and fruits can be removed in a landscape setting for a cleaner appearance. Do not prune the fronds that still have some green colour. Palms recycle nutrients from dead or dying fronds and use them for healthier fronds. Palms only have a set number of new leaves that can sprout and grow per year and removing fronds will not increase that number. If you cut off more than what will grow annually, you could be left with a pretty bare and bald palm. Left in place they form an attractive ‘skirt’ around the trunk.
Wind and salt tolerance: Salt tolerance moderate. With a particularly windy climate it is suggested to secure young palm to long solid stakes, to avoid that the wind could bare young and not very developed roots; specimens which are only a few years old might fear intense wind. Early Hawaiian Use The hard wood of the trunk were fashioned into spears. The trunks loulu were notched for climbing to gather the immature fruits and fronds. Older specimens still bear notches that can be seen today. The fronds were used for thatching and as plaiting such as hats and fans. Ornamental: Even if very rare this species must be cultivated as an ornamental tree, and planted in gardens and parks in tropical and sub-tropical climates either as a single specimen in small groves of three or more palms.
Culture in containers is possible although growth rates are slower. A bright patio will provide an excellent environment for young specimens which can eventually be planted in a sunny location.
Propagation: Sow fresh seeds buried half way in pot of clean, well drained potting soil, water daily and keep them at high temperatures (25 to 35 °C). Germination starts five week after sowing and can be spread over 21 weeks the seeds have a high germination rate and seedlings grow well in the right nutrient, temperature, and light conditions. Seeds do not require light for germination. Complete germination (98 to 100%) is promoted by removal of the outer husk from the seeds. This is most easily achieved by soaking the seeds for at least 24 hours. After removal of the outer husk the seeds can be germinated. Seedling plants of 30 cm can be put in ground/larger pot; Because these palms easily hybridize with other Pritchardias, claiming a specific species requires seed collection from wild populations. Seeds remain viable for 2 or more years. (llifle.com)
Pritchardia seeds have been shown to have a high germination rate and seedlings grow well in the right nutrient, temperature, and light conditions. The outer husk must be removed from the seeds in order for germination to occur. This is most easily achieved by soaking the seeds for at least 24 hours. After removal of the outer husk the seeds can be germinated by placing them in the dark for 4-8 weeks either in a planting medium (such as 3 parts perlite to 2 parts peat moss) or potting soil in seed flats or in zip lock bags. (National Tropical Botanical Garden)
Apply a complete palm fertilizer with minor elements as directed on label. Be certain that sufficient magnesium and potassium is present in the fertilizer component. This is especially critical for loulus in pots.
Magnesium and potassium deficiencies are two of the most serious nutritional disorders in palms. The deficiencies are characterized by bright yellowing (chlorotic) on leaf edges or streaking or the entire fronds yellowing. This can be difficult to reverse. Applications of Epsom salt, or magnesium sulfate (MgSO4), is good but does not last and is usually washed out of the soil in rainy periods. There are some very good slow release fertilizer spikes made especially for palms on the market which contain a good balance of minor elements with magnesium and potassium. Potted or younger loulu planted in the ground appreciate a foliar feeding of kelp or fish emulsion and Epsom salt monthly or bi-monthly. (Encyclopedia of Life curator Dr. David Eickhoff)
"This fast growing species does well in lowland urban areas, and is tolerant of many soil and weather conditions." (Encyclopedia of Life curator Dr. David Eickhoff)
Pritchardia remota is an easy to grow palm but not often available for the landscape. Pritchardia remota vary in shape. Specimens raised in dry and/or infertile soils tend to be smaller in stature with smaller leaves. Light also affects the plant's form while those grown in full sun are more compact. This palm prefers a sunny, well drained, and moist location. Growth rate: It is a slow growing, short stocky palm. Soil: It likes organic soil, but is adaptable to clay and loam both slightly alkaline and acidic. Good drainage is also important. Fertilization: Need a perfect fertilizer diet including all micro nutrients and trace elements or slow release fertilizer. Micro-nutrient deficiencies are occasional problems. If it doesn't get enough Mn and Fe (Iron), the leaves take on a rather unhealthy yellow colour. Micro-nutrient deficiencies only show up on soil with a high pH. Fertilize often for faster growth. Water Requirements: Needs regular water, do not let dry out between waterings. however it does not want to sit in continually wet, mucky soil. The roots and lower trunk can rot if soil is kept too moist. Light: Prefers full sun but will tolerate half day sun. Hardiness: It is adapted to tropical and subtropical climates, young plants are more cold sensitive. Maintenance: Remove dead fronds and spent fruiting stalks for a clean landscape appearance. Fronds can be left on the palm to form a skirt for natural settings. Palms recycle nutrients from dead or dying fronds and use them for healthier fronds. Palms only have a set number of new leaves that can sprout and grow per year and removing fronds will not increase that number. If you cut off more than what will grow annually, you could be left with a pretty bare and bald palm. Pest & Disease: Mealybugs and whiteflies underneath the leaves can present problems at times if not kept in check. A generous spray of water can wash them off. Ornamental: It is cultivated as an ornamental tree, and planted in gardens and parks in tropical and sub-tropical climates either as a single specimen or in groups. Culture in containers is possible although growth rates are slower. A bright patio will provide an excellent environment for young specimens which can eventually be planted in a sunny location. (llifle.com)
Comments and Curiosities
Conservation: This species is known from a single population on Nihoa, which is thought to contain approximately 600-700 individuals. Pritchardia seeds are damaged by rats that gnaw through the seed husk in order to obtain the nutritious endosperm. Pigs and goats damage seedlings both by herbivory of the young leaves and by trampling. The absence of introduced mammals on Nihoa protects Pritchardia remota populations from these factors that threaten the survival of other Pritchardia species. The populations are however vulnerable to other natural and human induced disturbance including hurricanes and fires. (National Tropical Botanical Garden)
Etymology: Pritchardia name is dedicated to William Thomas Pritchard (1829-1907), British official stationed in Fiji in the 19th Century, British counsul in Fiji, adventurer, and author of Polynesian Reminiscences in 1866. The specific epithet remota is from the Latin remotus, secluded or distant, literally "set aside", in reference to the range of this species restricted to the island of Nīhoa. (Encyclopedia of Life curator Dr. David Eickhoff)
Phenology: This is one of the fastest growing loulu and will reach flowering in a few years. One specimen (Nīhoa var.) planted to a site began flowering and fruiting at about 5 years of age. The flowers are showy en masse. In cultivated plants, the flowers of P. remota are a distinctive orange, while in their native habitat on Nīhoa they are yellow. In the wild on Nīhoa, this loulu has been observed flowering and fruiting in spring and summer. The fruit branchlets are short, hairless with small roundish (globose) pale greenish brown fruits on fruit stalks as long as the leaf stalks (petioles). Under cultivation this loulu seems to have no defined blooming and fruiting period. (Encyclopedia of Life curator Dr. David Eickhoff)
When the early Polynesians first settled on Nīhoa (between A.D. 1000-1700) this species was probably much more widespread. Loulu were cleared for agriculture to support the few inhabitants. Today, loulu concentrate on growing on the remains of the agricultural terraces built by the earlier residents. Humans lived on Nīhoa for sometime, but loulu did make a comeback. In July 1885, however, a fire accidentally set by someone in the large party of 200 accompanying Princess Liliʻuokalani's visit, destroyed most of the loulu on the island. Censuses since then indicate that the palms have been making a slow recovery over the years. Pritchardia remota is today considered rare and critically endangered with less than 700 found in a 1996 survey remaining on Nīhoa. Potential sites for re-establishment include Necker (Molumanamana), Laysan (Kauō), Midway (Pihemanu), and Kauaʻi. (Encyclopedia of Life curator Dr. David Eickhoff)
Pritchardia remota is related to P. glabrata, P. hillebrandii, P. kaalae, and P. maideniana. ("A Review of the Genus Pritchardia", pages S-3, S-8, S-40.)
On Nīhoa, loulu provide nesting and roosting habitat for seabirds. ("Natural History of Nihoa and Necker Islands" by Neal L. Evenhuis, 46, 62-63)
"Green fruits taste and have a texture like mild coconut-flavored gummy bears." (Encyclopedia of Life curator Dr. David Eickhoff)
Ni’ihau is known to have only one species of loulu. Up until the end of 2007, that species was named Pritchardia aylmer-robinsonii, after the owner of that private island. However, as these things happen every so often, it was found that the species on Ni’ihau is actually a variety of Pritchardia remota. P. remota was primarily known to be the single endemic species of the Island of Nihoa. Pritchardia remota is endemic to the Island of Nihoa which is two hundred miles northwest of Oahu; it is the highest island of the leeward group. Sightings of this species growing on Nihoa have been noted since the middle of the nineteenth century. These palms are quite conspicuous; they are found in two colonies on the island comprised of several hundred individuals. The colonies are located in two valleys appropriately named West Palm Valley and East Palm Valley. The location of the Pritchardia remota colonies on Nihoa is on account of the soil at the foot of basalt cliffs at the upper reaches of each valley where there is continual water seepage. In recent literature on this species, we find that it was considered to have four naturally occurring varieties in Hawaii on the Islands of Kauai, Maui, Nihoa and Ni’ihau, all of which are rare and endangered, a few critically so. The epithet is Latin for “remote”, an allusion to the small island of Nihoa where the name was first used to label the native species there. That variety carried a repeat of the epithet to distinguish it from the others. The other three varieties at one time were considered separate species: Pritchardia remota var. aylmer-robinsonii is endemic to the privately owned Island of Ni’ihau, where only two individuals are left in the wild. The epithet honors the island’s former owner Aylmer Robinson. It is a large tree with a trunk that attains a height of fifty feet or more and a diameter of one foot. The leaf crown is hemispherical to nearly spherical and is open because of the length of the felt-covered petioles. The leaves are semicircular, deep, almost bluish green, with deep and pendent segments. This variety is not considered a separate species in Hodel’s “Review of the Genus Pritchardia“. Pritchardia remota var. glabrata is endemic to Maui, where it grows on steep slopes at elevations of 1500 to 2000 feet. It is little known and probably not in cultivation. "(I do remember a tree labeled P. glabrata at the Maui Nui Botanical Garden when it was known as the Maui Zoo)". The epithet is Latin for “glabrous”. The glabrata variety is now considered a separate species, Pritchardia glabrata, endemic to the islands of Maui and Lanai. Pritchardia remota var. napaliensis is also considered a separate species. Endemic to the Island of Kauai, known as Pritchardia napaliensis, it grows in lowland rain forest and is rare and endangered. The epithet is Latin for “of Na Pali“, a coastal region of Kauai. The trunk of this variety attains a height of 25 feet. The leaves are small, dark green and wedge shaped. This variety has smaller flowers and smaller, black fruit which have a thinner pericarp. The fruit are 7/8 inch long by 3/4 inch wide. (Bill Chang)
A 1996 survey found a total of four plant populations of 680 palms on the island. Groves of P. remota palms grow in coastal mesic valley depressions in two valleys on Nihoa: The largest population grows in the West Palm Valley, while the three smaller populations are found in the East Palm Valley. Up to 50% of the pollen found in soil cores taken from lowland sites in the Main Islands comes from Pritchardia palms similar to this species. This is because these palms were once abundant there until around the year 1000, when the human population grew dramatically. The trees were cleared for agriculture and used for timber and firewood. Ancient Nihoans probably used the trees expansively as well , and this could have caused their water supply to be contaminated with guano. This, in conjunction with several drought years due to El Niño, could have caused the residents of Nihoa to give up and return to the Main Islands, which indeed happened before Nihoa was discovered by the Europeans in the 18th century. The species' longevity is also threatened by flash floods which have been noted to occur in the lower part of Nihoa's East Palm Valley, one habitat of the palm. P. remota provides a nesting place for Red-footed Boobies and a perching spot for Brown Noddies.
Melany Chapin writes: Starting from the uninhabited Northwestern island of Island of Nihoa, P. remota thrives with 600 to 700 palms in two forests within the intact dryland ecosystem. No rats or grazing animals have escaped to Nihoa so Pritchardia can be seen in a pristine state. The palm crowns create a thick canopy and the fronds cover the understory of the forest. These spectacular small palms have huge wavy leaves with drooping leaflet tips, extensive, short inflorescences and small fruits (Chapin 1990; Conant 1985). The island is owned by the Federal government and is part of the Hawaiian Islands National Wildlife Refuge.
Niiahu, or the forbidden island, is an inhabited, privately owned island, home of P. aylmer-robinsonii . Although only two wild trees are known, the residents cultivate the palm on Niihau; and it has been brought into cultivation elsewhere including Botanic Gardens. This medium sized palm has graceful, lax, green leaves that are somewhat weepy with small, black fruits.
"My own personal experiences with Pritchardia in southern California is that this is about the best and easiest good look species there is to grow, there... seems quite hardy in zone 9b and fast. This palm is from the Nihoa Island in the Hawaiian island chain, where it grows up to 20'... but I have seen taller individuals in cultivation in Hawaii. Has moderately folded leaves (costapalmate), with drooping tips, split about 1/3 their length and nearly semicircular. Just had a 2' seedling go through 27F freeze without frost for 5 hours, and plant nearly defoliated... maybe not as hardy as I thought (nearby P lanaiensis did a LOT better)" (Geoff Stein)
This species, from the tiny Hawaiian Islands of Nihoa and Niihau, where it grows in dry forest, is a moderately-sized palm, reaching a height of about 10 m (33 ft.). Its trunk is flexuous and slender, growing to around 15 cm (6 in.) in diameter; the crown is fairly dense, with numerous, deep green leaves that appear somewhat ruffled and sport drooping tips. Since its habitat is one of the driest and northernmost of all Pritchardia, it seems to be better adapted to Mediterranean-type climates than any other. Like most Hawaiian Pritchardia, it is critically endangered and cultivation in fact its only chance for survival. (RPS.com)
Pritchardia remota (formerly Pritchardia aylmer-robinsonii), Muolea, Hana, Maui, Hawaii. "This speciamen growing in Muolea along the Hana coast was formerly known as Pritchardia aylmer-robinsonii. In a recent review of the genus, it has been determined that it is a variety of the species Pritchardia remota." This species is endemic to the Island of Ni’ihau. Photo by Bill Chang
- Glossary of Palm Terms
- Pronunciation Key
Phonetic spelling of Latin names by edric.
Special thanks to Geoff Stein, (Palmbob) for his hundreds of photos.
Special thanks to Palmweb.org, Dr. John Dransfield, Dr. Bill Baker & team, for their volumes of information and photos.
Glossary of Palm Terms; Based on the glossary in Dransfield, J., N.W. Uhl, C.B. Asmussen-Lange, W.J. Baker, M.M. Harley & C.E. Lewis. 2008. Genera Palmarum - Evolution and Classification of the Palms. Royal Botanic Gardens, Kew. All images copyright of the artists and photographers (see images for credits).
Many Special Thanks to Ed Vaile for his long hours of tireless editing and numerous contributions.