Gigantochloa atroviolacea

Gigantochloa atroviolacea

Black bamboo or Java black bamboo, tropical black bamboo (Gigantochloa atroviolacea Widjaja, 1987) is a shrub species belonging to the Poaceae family.

Systematic –
From a systematic point of view it belongs to:
Eukaryota domain,
Kingdom Plantae,
Subkingdom Tracheobionta,
Spermatophyta Superdivision,
Division Magnoliophyta,
Class Liliopsida,
Subclass Commelinidae,
Order Cyperales,
Poaceae family,
Subfamily Bambusoideae,
Bambuseae Tribe,
Subtribe Bambusinae,
Genus Gigantochloa,
Species G. atroviolacea.
The term is synonymous:
– Gigantochloa atter var. nigra Gamble (1896).

Etymology –
The term Gigantochloa comes from the Greek “γίγας, -αντος” (gigas, -antos), i.e. giant and “χλόη” (chloe), i.e. grass, with evident reference to its vegetative aspect.
The specific epithet atroviolacea comes from the Latin “ater, atra, atrum”, i.e. black, dark and “violaceus, a, um”, i.e. violet, violaceous, in reference to the color that the culms take on after a certain time.

Geographic Distribution and Habitat –
Gigantochloa atroviolacea is a plant native to an area that includes: China (Hong Kong and Yunnan), Java and the Lesser Sunda Islands (Bali). This bamboo grows widely in West Java, especially in Banten and Sukabani district, as well as in Central Java. It was brought to the Indian Botanic Gardens in Calcutta more than 100 years ago.
Its habitat is that of low altitudes mainly on red lateritic soils. G. atroviolacea prefers to grow in arid areas on soils rich in limestone. The purplish-black color of the culms is more evident when growing in arid areas.

Description –
Gigantochloa atroviolacea is a rhizomatous, evergreen perennial plant, which forms rather dense tufts with erect cylindrical stems (culms) with curved apex, 8-15 m in height and 6-10 cm in diameter, equipped with aerial roots at the nearest nodes to the ground; the culms are hollow between the nodes with walls about 6 mm thick.
The internodes are 30-45 cm long; initially green in colour, then becoming blackish purple, possibly with thin green stripes, on which the whitish nodes stand out.
In the juvenile phase the culms are protected by deciduous triangular bracts, up to 20 cm long, covered with thick blackish hair.
From the nodes, except the lowest ones, various branches develop, of which one is predominant, with alternate, oblong-lanceolate leaves with a long pointed apex, 20-28 cm long and 2-5 cm wide, of an intense green colour.
The inflorescences are indefinite with sessile spikelets grouped at the nodes bearing 4 fertile flowers and one sterile, sessile one.

Cultivation –
Gigantochloa atroviolacea is an evergreen, perennial bamboo that is widely cultivated on a small scale in Central and West Java and has occasionally been introduced elsewhere in Indonesia (e.g. South Sumatra).
Outside Indonesia it is generally grown only in botanical gardens.
The culms and products made from them are sold in local markets, while furniture made from the culms is also occasionally exported.
This bamboo grows well in humid tropical lowland areas, with annual rainfall of 1,500 – 3,700 mm, relative humidity above 70% and average temperature of 20 – 32 °C.
In Java it is found mainly on red lateritic soils, reddish-brown soils and lateritic soils, but prefers drier calcareous soils. In arid areas the purple color of the culms is more accentuated.
It is an easy to cultivate and fast growing bamboo, it is considered one of the most ornamental bamboos due to its blackish culms and lush foliage, it can be cultivated in tropical and subtropical climate regions, its cultivation can be attempted in milder temperate-warm ones where temperatures just below 0 °C are exceptional events of limited duration.
It requires a position in full sun or light shade and is not particular about the soil, as long as it is draining, with preference for calcareous ones; despite being native to areas with high annual rainfall, it also grows well on moderately irrigated dry and rocky soils.
It is a slow growing bamboo, usually only 1 – 2 young shoots arise from the rhizome at the base of an old culm so the clumps are usually smaller than those of other bamboos.
However, it has been recorded that 15 culms may be present 2 years after planting.
Bamboos have an interesting growing method. Each plant produces a number of new stems each year: these stems reach their maximum height in the first year of growth, subsequent stem growth is limited to the production of new lateral branches and leaves. In the case of some mature tropical species, the new stem may reach 30 meters in height, with daily increases in height of 30 cm or more during the peak growth period. This makes them some of the fastest growing species in the world.
The culms reach their maximum length within 5 months. The average growth rate is approximately 9 cm per day.
The size of the culm increases with the age of the tuft; the average height is 3 meters in the first year after sowing, 6.4 meters in the 2nd and 9.3 meters in the 3rd; the average diameter increases from 2.2 cm in the first year, 5.5 cm in the 2nd, to 7.6 cm in the 3rd year after sowing.
Harvesting can begin 4-5 years after sowing. It is recommended to harvest only in the dry season.
The average yield of mature tufts is estimated at 20 culms per 3 years (or with 200 tufts per hectare, approximately 4000 culms per hectare every 3 years).
Traditionally, harvested culms are immersed in running or standing water for 15 to 30 days and then air dried.
Chemical preservation is possible by soaking the culms in a 5% borax solution for 3 days. Penetration into the walls of entire culms is approximately 50% for borax.
This plant reproduces by seed, if available, by division of rhizomes, with each portion having at least three culms, but more frequently by stem cutting to be carried out preferably at the end of the growing season, when the plant has accumulated the maximum reserves.
A portion of 2-3 year old culm with two or three nodes equipped with buds is used, placed obliquely or vertically on a sandy substrate rich in organic substance kept humid at a temperature of 24-26 °C.

Customs and Traditions –
Gigantochloa atroviolacea is a bamboo known by various common names; among these we report: black bamboo, Java black bamboo, tropical black bamboo (English); pring wulung, pring ireng (Javanese); bambu hitam (Indonesian); phai dam indonisia (Thai).
The culms, which have good characteristics of resistance and durability, have long been used in Java to make various traditional musical instruments, they are also used to build fine furniture, due to the characteristics of the finished product, and numerous handicraft objects; finally they are exported to a rather limited extent.
The culms are used for any type of construction and excellent for decorative purposes and for making furniture. It is a very desirable bamboo for making traditional musical instruments, crafts and fence panels.
The young shoots are eaten cooked as a vegetable.
The thin culm has specific characteristics that make it suitable for making the famous bamboo musical instruments angklung, calung, gambang and celempung.
In the past the culms were used exclusively for this purpose, but today the peculiar blackish culms have also attracted the attention of the craft and furniture industries, so much so that currently most of the culms disappear in these industries, creating a shortage of material for make musical instruments.

Preparation Method –
Gigantochloa atroviolacea is a bamboo used in its range both for the use of its plant materials and for food use; However, there are no known medicinal uses.
The young shoots are edible, they turn pinkish-yellow after cooking.

Guido Bissanti

Sources
– Acta Plantarum – Flora of the Italian Regions.
– Wikipedia, the free encyclopedia.
– GBIF, the Global Biodiversity Information Facility.
– Useful Tropical Plants Database.
– Conti F., Abbate G., Alessandrini A., Blasi C. (ed.), 2005. An annotated checklist of the Italian vascular flora, Palombi Editore.
– Pignatti S., 1982. Flora d’Italia, Edagricole, Bologna.
– Treben M., 2000. Health from the Lord’s Pharmacy, Advice and experiences with medicinal herbs, Ennsthaler Editore.

Photo source:
– https://inaturalist-open-data.s3.amazonaws.com/photos/332460132/original.jpeg
– https://sweetgum.nybg.org/images3/847/312/00044705.jpg

Attention: Pharmaceutical applications and food uses are indicated for informational purposes only, they do not represent in any way a medical prescription; we therefore decline any responsibility for their use for healing, aesthetic or food purposes.