Bamboo

Bamboo is a giant woody grass, and also their hollow jointed stem used as a cane or to make furniture and implements. It is also sometimes classified as a plant family related to the grasses but usually with thick woody stems. It grows chiefly in the tropics, and widely cultivated for its stems. The important varieties in South Asia include maling, reed and ringal bamboos.

Technically speaking, bamboos are any of the woody or treelike tropical and semitropical grasses of the genera Bambusa, Phyllostachys, Dendrocalamus, and allied genera like Arundinaria, Phyllostachys, or Sasa. It belongs to the family Gramineae.

They have woody, usually hollow stems with joints with stalked blades. They flower after years of growth. Certain species of bamboo can reach heights of from 20 to 30 meters (66 to 98 feet).

The stems of such a plant, used as a building material and for making furniture, poles, etc.

Origin of the word with the spelling 'Bamboo' dates back from 1590–1600. It was earlier bambu in Malay, and bambu in Kannada and other dravidian languages. It was also called bambus, bamboes or bambūsa.

A Flowering in bamboo is a botanical enigma. The factors that switch a bamboo plant from vegetative to flowering state are not fully understood. Nearly all species of bamboo seem to have their own life histories. Some species outside of the Indian-Asian tropics, and a very few in these tropics, have populations composed of individuals that grow to maturity and then flower and seed annually for many years. The culms that flower often die after the fruit has developed but other culms and rhizomes survive and perpetuate the stand. Many of the more common Indian-Asian species have populations made up of individuals that seed synchronously at regular and long supra-annual intervals. After growing by rhizome and branch production for a species-specific period of 3-120 years, nearly all the members of one species in one area produce wind-pollinated flowers, set large quantities of seed and die. This seed germinates immediately or when the first rains come.

According to their flowering habits, there are three types of bamboo:
(i) those that flower annually or nearly so, e.g., Arundinaria spp. in India and Schizostachium brachycladum in Thailand;
(ii) those that flower gregariously and periodically;
(iii) those that flower irregularly.

The flowering habit of Bambusa spp. and Dendrocalamus spp. in the tropical regions of Asia and of Phyllostachys and other genera in Japan belongs to types (ii) and (iii). P. edulis flowers sporadically, and the flowering occurs in small areas or in a few clumps. Periodical and gregarious flowering occurs in cycles; the cycles are more or less constant for a species in a given locality but differ between remote locations. Below are the flowering cycles of some Indian species:

Years	Species
1	Indocalamus wightianus, Ochlandra scriptoria, O. rheedii, O. stridula
7	O. travancoria
16-17	Thamnocalamus spathiflorus
25-65	Dendrocalamus strictus
28-30	Thamnocalamus falconeri, Chimonobambusa falcata
30	Oxythenantera abyssinica, Melocanna baccifera, Bambusa arundinacea
30-40	Dendrocalamus hamiltonii
30-60	Bambusa tulda
35-60	Bambusa polymorpha
45-55	Chimonobambusa jaunsarensis
47-48	Thyrostachys oliveri
48	Bambusa copelandii, Pseudostachyum polymorphum
60	Phyllostachys bambusoides (120 years in Japan)

Although a wide range of research and discussion is going on, the flowering of bamboo is still unexplained and mysterious. There are several theories concerning the causes of flowering and death of bamboo:

a. Pathological theory, which postulates that flowering is brought on by the destruction of bamboo by organisms such as nematodes, fungi, insects and parasites;

b. Periodical theory, which proposes that the cycle starts with bamboo regeneration through asexual methods (rhizome and culm elongation), reaches maturity and results in flowering;

c. Mutation theory, which considers that bamboo regeneration through any methods of asexual propagation is mutation and brings about flowering of bamboos;

d. Nutrition theory, which proposes that flowering and fruiting are usually the result of a physiological disturbance arising chiefly from the poor growth of the vegetative cells, brought about by an imbalance in the carbon-nitrogen ratio;

e. Human theory, which states that human practices such as cutting and burning induce bamboo flowering.

It is generally believed that flowering in bamboo results in death of the bamboo. Subsequent to flowering, bamboos show different types of mortality behaviour. In some bamboo, parts above the land perish or only underground parts die, complete plant die except rhizomes or the plant dies in totality where regeneration is possible only through seeds.

f. Flowering does not result in the death of either aerial or underground parts, e.g., some species of Arundinaria, Phyllostachys, Bambusa atra.

g. Flowering results in complete death of aerial parts only, the rhizomes remain alive and plants regenerate, e.g., Arundina amabilis, A. simonii, Phyllostachys nidularia.

h. Flowering results in complete death of aerial and underground parts and regeneration is only possible from seeds, e.g., Melocanna bambusoides, Thyrostachys oliveri, Bambusa arundinacea, B. tulda.

Nearby pages
Bamboo curtain, Bamboo shoot, Bamboozlement, Bamborough Castle, Bambouk