Balaka microcarpa

Balaka (bah-LAHK-ah) microcarpa (migh-kroh-KAHRP-ah)
Hawaii. Photo by Timothy Brian.
Scientific Classification
Genus: Balaka (bah-LAHK-ah) Species: microcarpa (migh-kroh-KAHRP-ah)
Synonyms
None set.
Native Continent
Oceania
Morphology
Habit: Solitary Leaf type: Pinnate
Culture
Survivability index
Common names
None.

Habitat and Distribution

Fiji. The known range of this palm is very small, occurring immediately north of Suva, Viti levu, only in the forests of Coloisuva and Savura Creek.

Jeff Marcus Garden in Hawaii. Photo by Paul Craft.

This species of Balaka grows as an understorey, rarely semi-emergent palm of the wet forests of Coloisuva and Savura Creek at an altitude of 50-300m with an annual rainfall in excess of 4000mm and with no dry season. In the early 1980s, Dr Julian Ash of the University of the South Pacific made a detailed ecological study of this palm over a three year period and found it to be very slow growing with palms maturing at about 5 m in height when they would be about 45 years old. Flowering and fruiting occurs throughout the year. The oldest palm he observed was estimated to be 85 years old. Annual fruit set is very variable with about 180 fruits on each inflorescence each year. Only about 0.1% of these fruit survive to become a mature palm. No observations were made on seed dispersers and so gravity and water are believed to be the main agents. (naturefiji.org)

Description

This species of Balaka is usually a small palm, but it can grow up to 13m in height, with an 8 cm diameter trunk. The trunk is green with distinct nodes below the crown shaft, but lower down along the trunk it becomes grey-brown, and is usually heavily adorned with epiphytes, moss and lichen of various colours. It has a compact crown with 7-10 ascending fronds that are up to 2 m in length, with large, well spaced dark green leaflets. As with several, if not all the Balaka, the fronds are considerably longer in those palms growing in full shade than those in open areas. The crown shaft is slight and dark green with inflorescences emerging beneath it. The inflorescences are two or three times branched with a long petiole and are often held erect. The fruit are small, oval in shape; about 2 cm long by 1 cm wide, and are bright orange-red when mature. Young palms are conspicuous, with characteristic entire leaves, the transition from the entire leaf to the pinnate form occurs on average after the 28th leaf. (naturefiji.org) Editing by edric.

To 15 m tall. Stem to 8 cm diam. Leaves 5–10, ascending-arching, slightly recurved, stiffly ascending in open areas with higher light, 1.6–2.2 m long; sheath 30–40 cm long, sometimes dark colored; petiole lacking or to 5 cm long (Fig. 20); blade to 1.2–1.8 m long; pinnae 9–16 per side, elongate-sigmoid, margins converging toward base and apex and there obliquely truncate and toothed, to 55 cm long, to 11 cm wide, thickleathery, distinctly forward-pointing, midrib prominent adaxially. Inflorescences 2 or 3 per plant, infrafoliar, 60–85 cm long, 2– or 3- branched; peduncle to 30–35 cm long; rachis 15–20 cm long; up to 25 rachillae, these 12–30 cm long, spreading; triads nearly to apex of rachilla. Staminate flowers with 20–30 stamens, pistillode ca. equaling stamens or exceeding them, thick, stubby, flexuous. Fruit 1.4–2.0 × 0.7–1.0 cm, ovoid, bright red; fruiting perianth 5 mm long; endocarp 1.3–1.8 × 0.6– 0.9 cm, with 4, prominent, sharp longitudinal ridges and very short rostrum 3 mm long. (iucn.org)

Notes: The ascending to arching leaves with short petioles, elongate, thick-leathery, strongly forward-pointing, obscurely nerved pinnae, and small fruits distinguish Balaka microcarpa. Seedlings and small, juvenile plants have handsome, simple, bifid leaves until they attain about a meter in overall height and have a short stem about 30 cm tall. The unusually short petioles and stiffly ascending leaves trap and collect falling litter from the forest canopy, channeling it into the center of the plant. In disturbed areas where the forest is more open or in areas with a naturally low canopy, Balaka microcarpa is an emergent species and its leaves are frequently stiffly ascending. In these instances, the stiffly ascending leaves and thick-leathery, forward-pointing pinnae immediately conjure up images of a New Caledonia Basselinia pancheri or B. gracilis. (iucn.org)