|Socratea (sohc-rah-TEH-ah) exorrhiza (eks-ohr-REE-saw)|
Hilo, Hawaii. Photo by Timothy Brian.
Habitat and DistributionSocratea exorrhiza is found in Bolivia, Brazil North, Colombia,
Cashapona grows quickly, has a very small, light canopy, and develops well from naturally dispersed and discarded or thrown-out seeds. Maintenance is minimal, and it grows well with almost any crop. These factors combine to make it a common species in non-flooded fields and fallows. Rainforest. A common species in non-flooded fields and fallows. Lowland to premontane rain forest, at elevations from sea level to 1,000 metres.
Socratea exorrhiza, the Walking Palm or Cashapona, is a palm native to rainforests in tropical Central and South America. It can grow to 25 metres in height, with a stem diameter of up to 16 cm, but is more typically 15–20 m tall and 12 cm in diameter. It has unusual stilt roots, the function of which has been debated. Many species of epiphyte have been found growing on the palms. The palm is pollinated by beetles, and various organisms eat its seeds or seedlings.
Cashapona is a fast-growing, single-stemmed, evergreen palm tree growing from 8 - 25 metres tall. The unbranched stem can be 12 - 18 cm in diameter; it has stilt-like aerial roots near the base that can be up to 3 metres long; and is topped by a crown of about 7 leaves that can be 1.5 - 2 metres long.
The tree is often used locally, harvested from the wild for food, construction materials and medicine.
Probably the most famous of the stilt rooted palms, with the roots coming from up to 2 m (6 feet) from the ground. Even young plants have no trunk going into the soil, only roots. The palms themselves can grow to 20 m. It has a small head of plumose, deep green leaves, up to 2 m long, with a greenish blue crownshaft.
Canopy palm. Stem solitary, 10-20 m tall and 10-20 cm in diameter, supported at base by a few, thick, brown stilt roots with numerous short, white root spines. Leaves 1.5-3.5 m long; pinnae 15-25 on each side, longitudinally split into 2-18 unequal segments, these 40-90 cm long. Inflorescence axis 30-60 cm long; branches 5-20, to 40 cm long. Male flowers about 1 cm long, with 17-65 stamens. Female flowers about 5 mm long. Fruit elongate, 1.5-2.5 cm long, smooth. Editing by edric. (Borchsenius, F. 1998)/Palmweb. Editing by edric.
Socratea exorrhiza need full sun to partial shade with moist soil. We grow ours under 25% shade all year long. In the greenhouse, we use a soil mix consisting of 2 parts peat moss to 1 part loam to 2 parts sand. The soil mix is kept constantly moist all year long. We fertilize the palm monthly during the spring and summer months with a balanced fertilizer. During the winter months, we do not fertilize them. In containers, the palms are fairly slow growers and they need to be repotted every couple of years. The stilt roots will sometime grow outside of the container, giving it a unique look in the greenhouse. Seeds germinate in 45-60 days at 75°F (24°C). USDA zones 10b-11.
S. exorrhiza flowers mostly during the dry season, and is considered to be beetle pollinated, being frequently visited by species of Phyllotrox (Derelomini) and Mystrops (Nitidulidae). Seeds weigh around 3.5 g and are around 2 cm long and 1.5 cm wide, only around 45% of them germinate and around one quarter of these die.
Comments and Curiosities
Socratea exorrhiza or Stilt Palm is a large species of monoecious palms native from Central America to the Amazon Rainforest. They are sometimes called Walking Palms because of their prominent stilt-like roots. If the light is better on one side of the palm, the roots will grow into the lighted area and roots on the low light side tend to die off. Thus, the palm itself moves more into the light. In nature, stilt palms will reach about 65 feet (20 m) tall. The roots have small, white, conical spines. Ramified inflorescence with white flowers. Fruits turn yellowish green when ripe. The dark green, pinnate leaves will reach up to 6 feet (2 m) in length, with the tubular sheaths forming a conspicuous crownshaft. The crownshaft is often bluish-green.
Uses: Young apical buds - cooked as a vegetable. A good flavour. Eating the apical bud leads to the death of the tree since it is unable to make new growth or side branches. The trunk is used in the construction of houses and other structures, as well as hunting spears. It is usually split lengthwise before it is used, but it can also be hollowed out and used as a tube. The yellow fruits are edible. The spiny roots are used for scraping coconuts (Cocos nucifera) and yucca (Manihot esculenta). The inner part of the stilt roots is used as a male aphrodisiac. The stem is used to make a plaster to cicatrize the umbilical cord of newborn infants. A decoction of the leaves is used to wash the penis for treating gonorrhea. Smoke from the burned fruit is used for remedying gonorrhea and urinary diseases. A decoction of the seeds is used to wash the penis for treating gonorrhea. The tree grows quickly, has a very small, light canopy, and develops well from naturally dispersed and discarded or thrown-out seeds. Maintenance is minimal, and it grows well with almost any crop. Other Uses. The stems are used for thatching. The seeds are used as beads for making necklaces etc. The outside of the wood is hard and durable, although the inside is soft and pithy. The plant has an important local role in construction - the trunk is used in the construction of houses and other structures, posts, fences, palisades etc. It is usually split length-wise before it is used, but it can also be hollowed out and used a tube. The gigantic trumpets of the Uaupes River Indians are made of sections of this palm, wrapped with long strips of Epema grandiflora.
Corner in 1961 hypothesised that the unusual stilt roots of S. exorrhiza were an adaptation to allow the palm to grow in swampy areas of forest. No evidence exists that stilt roots are in fact an adaptation to flooding, and alternative functions for them have been suggested. John H. Bodley suggested in 1980 that they in fact allow the palm to "walk" away from the point of germination if another tree falls on the seedling and knocks it over. If such an event occurs then the palm produces new vertical stilt roots and can then right itself, the original roots rotting away. Radford writes in the December 2009 Skeptical Inquirer that "As interesting as it would be to think that when no one is around trees walk the rainforest floor, it is a mere myth", and cites two detailed studies that came to this conclusion. Other advantages of stilt roots over normal roots have since been proposed. Swaine proposed in 1983 that they allow the palm to colonise areas where there is much debris (for example, dead logs) as they can avoid it by moving their roots. Hartshorn suggested in 1983 that stilt roots allow the palm to grow upwards to reach light without having to increase the diameter of the stem. The roots make the palm more stable and therefore allow it to grow taller and more quickly than if they did not possess them. They also allow the palm to invest less biomass in underground roots than other palms, therefore leaving more energy to be used in growing above ground. It was also thought that the roots may confer an advantage when the palm is growing on a slope, but no evidence has been found that this is the case. (Bodley, John; Benson, Foley C. (March 1980). "Stilt-Root Walking by an Iriarteoid Palm in the Peruvian Amazon". Biotropica. jstor: The Association for Tropical Biology and Conservation. 12 (1): 67–71.)
Leaf morphology: Leaves of S. exorrhiza that grow in the sun are thicker, have more trichomes and more stomata than those that grow in the shade.
Predators: White-lipped peccaries predate a large proportion of the seeds of S. exorrhiza and play an important role in limiting their population.
Reproduction: S. exorrhiza flowers mostly during the dry season and is considered to be beetle pollinated, being frequently visited by species of Phyllotrox (Derelomini) and Mystrops (Nitidulidae). Seeds weigh around 3.5 g and are around 2 cm long and 1.5 cm wide, only around 45% of them germinate and around one quarter of these die.
Iriartea ventricosa has similar roots to S. exorrhiza.
- Glossary of Palm Terms
- MODERN BOTANICAL LATIN
- "Just To Be Clear"
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).
Borchsenius, F.1998. Manual to the palms of Ecuador. AAU Reports 37. Department of Systematic Botany, University of Aarhus, Denmark in collaboration with Pontificia Universidad Catalica del Ecuador.
Bodley, John; Benson, Foley C. (March 1980). "Stilt-Root Walking by an Iriarteoid Palm in the Peruvian Amazon". Biotropica. jstor: The Association for Tropical Biology and Conservation. 12 (1): 67–71.
Many Special Thanks to Ed Vaile for his long hours of tireless editing and numerous contributions.