Archive for category Species

National Bamboo Mission Uttarakhand

Uttarakhand, the land of temples, abode of Lord Shiva and Guru Gobind Singh alike, is now all set to pioneer bamboo agroforestry, due to its unique geographical location, stretches of well drained alluvial soil in the Terai belt and abundance of water- both, ground and rain.

The recently revised bamboo policy, with its de-classification as a timber (erstwhile) to its correct botanical classification of a"Grass", offers a window of opportunity for bamboo based enterprise. Government is thus focusing on developing bamboo based industry clusters, in areas endemic to bamboo, where, Uttarakhand fits the bill very well.

The task may seem Herculean, but it is surely possible to create Bamboo Based Clusters of Industry in the state of Uttarakhand, and to my mind we will need to focus on the following areas.

  • We will first need to set up a pilot unit( s )-  ( both, for agro-forestry as well as value addition endeavors )-Under the helmsman-ship of Forest Research Institute, Dehradun, with regional centers at various state agricultural universities, including GBPUAT- so that farmers get acquainted with bamboo as a crop. Some farmers, who pioneered undertaking bamboo agroforestry earlier, did not have a pleasant experience because of lack of proper markets at that point of time, when bamboo was still a regulated commodity. In light of the de-regulation, and prospects of bamboo industry coming up- we would have to do the confidence building exercise- where FRI, GBPUAT and other Universities/Institutions will need to show the way and bear the Olympian torch- for both aspects of Industry development- agriculture/agro-forestry (the source of raw material) and value-addition (product development and marketing). FRI, GBPUAT and other Universities, will perhaps, need to liaise with lead institutions like NID, IPRITI etc. to evolve suitable products and suitable markets. A collective effort is imminent to make this Bamboo Mission a reality.

Collectively,

  • We will need to research bamboo utilization in paper industry, and work on developing linkages between farmers and the paper units ( for example Century in Lal Kuan). I believe, bamboo requires a different production line, so Century will only do so, if it is assured of sustainable supply of bamboo . Maybe, a buy-back rate could also be fixed to build up confidence of the farmers.
  • We will need to develop nurseries of elite plant material to cater to the requirement of extension. The endemic bamboo species, which grow well in Uttarakhand are Dendrocalamus Strictus, B. Balcooa, B. Nutaans, Bambos and  Hamiltonii ( mid altitude). Oliverii  and D. Stocksii were recently introduced and have been found to be performing well. The forest areas have primarily Strictus. For enterprise based cultivation and extension excellent clones have been developed by FRI and GBPUAT, amongst other regional Institutes. Farmers/growers must try to procure these elite clones- namely, Balcooa, Nutaans, Oliverii and Stocksii for the plains and Hamiltonii for the hills. Each of the above elite clones has specific applications, so a judicious selection needs to be done, for choice of planting material.
  • Nurseries should be preferably vegetative- because survival rate of rhizomes is lot better than cuttings, or TC. We will need to develop local nurseries- to minimize transport and incidental damage-for the plant requirements of projected plantation program in the vicinity. Getting Plants from a distance is a messy and cost intensive affair, not to mention the transit damage, and the issue of acclimatization
  • Planting Schedules will need to be optimized- and Nursery production geared up to provide plants at the RIGHT TIME. There is no point having the plants in July-- because the best time to plant is Feb !!!!! . However, where water is a scarcity, or planting is to be undertaken in rain-fed area, the next best option is, indeed Pre-Monsoonal- but again, the choice of planting stock should be non other than RHIZOMES- because they have a higher chance of survival.
  • There are pockets of Bengali and Bihari immigrants /migrants in Uttarakhand, where weaving clusters could be developed. The native art of weaving existed, but died a natural death because of paucity of bamboo, due to forest restrictions. In light of the revision of Bamboo Policy, there is every likelihood of bamboo being available. We will probably need to establish weavers clusters and nurture them, till they can sustain themselves.
  • Construction industry- Fully solid or thick walled species have a great utilization in the construction industry- may it be the scaffolding, or cheap housing.
  • Hand Made Paper could also be made.
  • Furniture- Industry- requires specialty bamboo- and Uttarakhand could follow suit.
  • Logistics-paperwork for Inter-state movement of bamboo- There is still a lot of confusion amongst farmers, with regards to inter-state transportation of bamboo. Though, its been reiterated , post de-regulation, that the "permit-regime" has been archived, but there are still loop-holes, probably because of lack of understanding of the ordinance, or else, lack of will for proper implementation.
  • Farmers undertaking bamboo as a crop- would need to have it duly registered in their land records (khasra). This document is said to be a valid proof of origin of bamboo on private land.
  • To encourage extension and emergence of bamboo based enterprise, the Government could relax the Land Ceiling Slabs for bamboo agroforestry. It could be on the lines of the Tea Industry- where land is attached to the production Unit, and the ceiling is lifted. Its classified as an Industry. A similar scheme could be devised to encourage bamboo entrepreneurship.  
  • Energy- I have been following this topic but I gather bamboo based ethanol or bamboo based briquettes are not economical, as compared to other sources of fuel. Hopefully I am wrong. !!!!! 

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Bamboo Propagation

India has about 1200 odd bamboo species- out of which the commercially important ones have been prioritized by the Government, under the National Bamboo Mission.

As a farmer and a bamboo-entrepreneur based in Uttarakhand, totally solid species, also called the Iron bamboo are of special interest.

Currently nursery works are underway - to cater to our planting targets of next year.

Bamboo Multiplication is primarily done by rhizomes, Old bamboo plant is dug out, the culms separated with a bit of root-stock in each, which are then planted out.

This year- we have made our own nurseries using the rhizome method of the following species

  • Thick walled Bambusa Balcooa- with about a hole of about 1 cm dia
  • Thick Walled Nutaans- with about 1 cm hole
  • TOTALLY SOLID NUTAANS-- 2 stains
  • TOTALLY SOLID STOCKSII- 3 stains
  • Oliverii
  • Guadua ( experimental)

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Iron Bamboo Nurseries- Guroo Farms

Due to a proposed restriction on export of Shisham, we have, over the last 2 years, established an experimental Bambusetum, of about 8 bamboo species, including 2 of the rare Iron Bamboo varieties, namely, Dendrocalamus Stocksii and Thyrostachys Oliverii at Guroo Farms in the Terai Belt of Uttarakhand and Uttar Pradesh, India. Besides the afore-mentioned Iron Bamboos, we also have planted Nutaans and Balcooa, both being loosely clumped, thick walled and with straight growing habits.

Further, I would like to thank our Prime Minister, Mr. Modi to have taken the initiative of having Bamboo de-listed as a forest-produce, thereby facilitating ease of trade, and thus giving an impetus to bamboo agro forestry systems. We, as a Sovereign Nation have been sleeping over the error of classification which has resulted in bamboo not having been exploited to its optimum potential. Thus, China is way ahead of us, despite the fact that we, as a country, have a considerable bamboo stand in our forests, and also have agro-climatic zones that support bamboo agro-forestry systems. Botanically, bamboo is a grass and not a tree- an anomaly that should have been sorted out, way back.

I am trying to locate a reliable source of Guadua Bamboo, which is said to be an excellent species for Terai. It is one of the toughest TIMBER BAMBOO, ideal for construction.

My aim is to get about 10 to 15 acres under bamboo cultivation over the next 2 to 3 years.

Another issue that plagues my mind is the choice of the under-story crop for the first 2 years, till the bamboo stand establishes fully.

Does Turmeric fit the bill??

 

References

http://www.downtoearth.org.in/news/india-opposes-cites-move-to-regulate-trade-in-all-species-of-dalbergia-56884

https://en.wikipedia.org/wiki/Dalbergia_sissoo

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Babool- Gum Arabic Acacia Nilotica Wood for Handicrafts

The Babool or the Indian Gum, Nilotica (linn), Willd ex del is also known as kikar, babur etc. and is indigenous to the Indian Sub-continent. It is found in Deccan and Thar.

A. nilotica is a multipurpose tree. Its timber is valued by rural folks.

Uses

Tooth brushing- The tender twigs are used as a toothbrush (Datun)

Gum arabic- The gum of A. nilotica is also referred to in India as Amaravati gum

Hedges- V. nilotica is thorny and hence makes a good hedge.

Physical Properties of the Wood
The hard wood is heavy and tough. The average weight is about 785 kg/m3 at 12 per cent moisture content. It is somewhat coarse-textured and has interlocked grains. The wood is dull and somewhat rough without any characteristic odour or taste. The strength properties of wood are given below

 

Babool

Teak

  Green Air Dry Green Air Dry
Moisture content per cent 70 12 76.6 12
Static Bending        
(a) Fibre stress at elastic limit (kg/sq cm) 421 487 509 651
(b) Modulus of rupture(kg/cm2) 776 894 841 959
(c) Modulus of elasticity (1000 kg/sq cm) 977 1128 1097 1196
Impact bending        
(a) Fibre stress at elastic limit (kg/sq cm) 1085 1306 1085 1121
(b) Maximum height of drof in impact binding (cm) 130 104 91 71
(c) Modulus of elasticity (kg/sq cm) 108400 140100 160600 166800
Compression parallel to grain (kg/sq cm        
(a) Compressive stress at  207 260 311 376
(b) Maxi. Crushing stress  354 536 415 532
(c) Modulus of elasticity 101800 118000 129800 137400
Compression perpendicular to grain (kg/sq cm)        
(a) Compressive stress at elastic limit  91 124 86 101
Hardness-load in kg to embed 1.128 cm diameter ball to half diameter        
(a) Radial  720 824 557 502
(b) Tangential  755 855 551 524
(c) End  671 915 486 488
Shear paralled to grain (kg/sq cm)        
(a) Radial  119 168 90 97
(b) Tangential  143 192 100 108
Tension perpendicular to grain (kg/sq cm)        
(a) Radial 89 71 68 58
(b) Tangential 107 93 79 66

Working and Finishing Properties
In its green state, It is an easy wood to convert and resaw. However, it becomes harder and tougher when seasoned. It works well by hand machines and finishes to a good surface. Its working quality index based on quality of worked surface and ease of working is 84 compared to 100 for teak.
Timber
The wood is widely used for construction as posts, rafters, beams and in door frames. It is one of the most favoured timbers for all types of agricultural implements like ploughs, harrows, crushers and rice pounders, and is extensively used in card building, for yokes, shafts, wheels and body work. Babul wood is also recommended for certain types of sports and athletic goods like clubs, wall bars, parallel bars, etc..

Fuelwood- and charcoal. Its charcoal is considered to be superior to charcoal from other species.

Resources

http://www.frienvis.nic.in/WriteReadData/UserFiles/file/pdfs/Babul.pdf

https://en.wikipedia.org/wiki/Vachellia_nilotica

 

We have found it to be an excellent raw material for various handicrafts

See some of our Babool/Acacia products on OUR EBAY STORE

HTTP://STORES.EBAY.COM/BAMBOOWOODCRAFT USA STORE

HTTP://STORES.EBAY.CA/BAMBOOWOODCRAFT CANADA STORE

HTTP://STORES.EBAY.COM.AU/BAMBOOWOODCRAFT AUSTRALIA STORE

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Bamboo as a Crop

Off-late, BAMBOO (Gramineae (Poaceae), subfamily Bambusoideae) has stolen my interest, and I have been collecting commercially viable genotypes. I came across this interesting genotype of Bambusa Balcooa, with almost non-existent inter-nodal cavity ( in the lower 60% of the bamboo- which gradually increased to about 2 to 3 cm in the upper third) . I plan to propagate this particular bamboo for its possible use as a substitute to hardwood for our handicrafts. 

Description
Bamboos are giant woody grasses, with about 1300 species in approx 180 genera. B
ambusoideae are distributed in tropics.

Bamboo plants, usually perennial, consist
of an underground root system and rhizome mat from which culms grow. These (culms) are usually hollow, primarily made of cellulose, hemicellulose and lignin. Diameter of up to 20cm or more has been seen in some species, with a height of 10–40m, which is achieved in about 3–4 months.

Bamboo has long fibre- 1.5 to 3.2mm in length, comprise 60–70 per cent of the culm’s weight, thus a desirable raw material for paper production. Bamboo provides a high biomass yield, is strong and its calorific value is comparable to wood.

Bamboos can be-sympodial or monopodial. The flowering cycle can be anywhere from 15 to 120 years.

Ecological requirements
Most species need warm and humid climates. There are drought-resistant strains, such as Dendrocalamus strictus which can survive on a minimum of 750–1000mm annual precipitation.

Bamboos prefer light, well-drained sandy loams, with abundant organic matter. The optimal soil pH range is between 5 and 6.5.

Propagation
Conventional propagation is done by: seeds or by vegetative methods (
the planting of offsets, culm cuttings or branch cuttings).

Crop management
Planting density tests of Dendrocalamus strictus in India suggest that the high density populations, something like sugarcane, could yield as much as 27t of biomass/ha- measured over 18- month period.

Fertilization- has been shown to lead to an increased number and weight of rhizomes. A nitrogen-rich, fast-release compound fertilizer should be used in the spring, a month before sprouting. Studies in China have concluded that for every 1000kg of bamboo vegetable matter produced, 2.7kg of nitrogen, 3.6kg of potassium and 0.36kg of phosphorus must be added to the soil.
Suggested fertilizer levels for bamboo resulting from tests in India

Fertilizer Amount (kg/ha)
Nitrogen (N)-  100 (kg/ha)
Potassium-  (as K2O) 50 (kg/ha)
Phosphorus - (as P2O5) 50 (kg/ha)

Production, Processing and utilization
Bamboo is harvested manually with knives.

It was previously believed that clear felling was harmful to bamboo stands, but tests in India have shown that clear felling of the stand led to vigorous growth.

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Bambusa Balcooa

One of the species that I have collected in my bambusetum/bambusarium is Bambusa Balcooa, aka Female Bamboo. It is a tropical clumping species of bamboo. It is found in N.E India, Tarai area of Uttar Pradesh etc. Some of the clones are very thick walled.

This bamboo species is often used in scaffolding, for paper pulp or wood chips. It is a popular building material for houses and bridges and on a lesser scale, used for baskets, mats, roofing. Young shoots are eaten and leaves are used as fodder.

The culms of Bambusa Balcooa are about 12-22 m in height, and about 6-15 cm in dia, thick walled ( the cavity is about 30% of the culm). Nodes are thickened with a whitish ring above, and have short small hair below. Internodes are about 20-40 cm long.

Shoots are blackish/green yellow in color. Culm sheaths are brown, sometimes with dark brown hair.

Branches: Several Branches occur from middle of the culm to the top. Branches from the lower nodes are leafless and hard, and sometimes thorn-like.

Leaves: Leaves are narrow and are on average 15-30 cm long and 25-50 mm broad.

Seeds: Gregarious flowering every 35-45 years.

Habitat: Bambusa balcooa grows in tropical monsoon climates.

Mechanical properties: The compressive strength ranges from 39.4 to 50.6 N/mm2 in green and 51.0 to 57.3 N/mm2 in air dry condition. Modulus of rupture varied between 85.0-62.4 N/mm2 in green and 92.6-69.6 N/mm2 in air dry condition. Modulus of elasticity 7.2-10.3 kN/mm2 in green, 9.3-12.7 kN/mm2 in air dry condition (Kabir et al. 1991).

References

Malay, D,Bhattacharya, S, Singh, P, Filgueiras, T S, Pal, A. 2008. Bamboo Taxonomy & Diversity in the Era of Molecular Markers. Advances in Botanical Research 47: 225 – 268.
Guadua Bamboo Costa Rica:
http://www.guaduabamboo.com/bambusa-balcooa.html#ixzz28Oocjo8v\

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Iron Bamboo Processing and Preservation

As a person undertaking agro-forestry of bamboo, we process Iron Bamboo for Handicrafts, Martial Art or Medieval Replica Weapons for Self Defense, which involves specialized methods and techniques of processing and preservation, to increase its durability.

Preservation techniques-

The empirical wisdom or popular knowledge, of indigenous people, peasants, farmers and artisans, has been developed through centuries in all the continents and has resulted in well-known methods and techniques to effectively preserve bamboo. Traditional methods are generally cheaper to implement and can be done without any special equipment.

For proper Preservation of iron bamboo, it must be harvested/cut early mornings, before sunrise, in winters - on a waning moon.** (This is a controversial topic, scientists argue over the truth behind this “peasant knowledge”. Nevertheless, detailed studies show remarkable differences with untreated bamboo, when harvested at specific hours and moon phases. The starch content is lowest between waning gibbous and last quarter between the 6th and 8th day after full moon due to the higher gravitation of the moon. On the basis of photosynthesis, in the course of the morning, bamboo starts transporting starch from the roots into the leaves.

Soaking- After harvest, bamboo is stored in running water for 3-4 weeks to leach out starch.

Chemical Treatments ( any one -to be done immediately after harvesting or after soaking)-

  • CCA (copper-chrome-arsenic composition, in the proportion 3: 1:4) is good for bamboo, but has associated health hazards. Thus, it has to be used judiciously, if at all. Bamboo products are tanalised, impregnated under pressure or boiled with chromated copper arsenate (CCA) to protect against rot. CCA is effective but toxic/carcinogenic.

  • ACA- Ammoniacal copper arsenate penetration in bamboo is effective against fungi, bacteria and insects. However, ACA is eco-toxic non-degradable.

  • CCB and CCBF  - commercially ASCU.

  • Boric acid, borax and boron are cheaper than CCA and less poisonous. This is used at a concentration of  2.5 per cent each, to be dissolved in hot water. The preservative, (disodium octaborate- which forms as a result of the reaction), is easily soluble in water. This process is only recommended for bamboo culms that would not be exposed to water or rain. Boron salts are effective against borers, termites and fungi (except soft rot fungi), and is widely recognized to be environmentally acceptable and safe for the mammals.

  • Other alternatives methods:Treatment of bamboo with limewater.

  • Drying of bamboo before use is necessary since dry bamboo is stronger and less susceptible to biological degradation than moist bamboo. In some experiments carried out it was found that Acetic acid (Vinegar), completely prevented moulds/fungus incidence during the drying process. (Tang et al., 2009).

  • Following the drying, the bamboo is TRADITIONALLY smoked by storing it above a fireplace, to blacken the culm. This, however, may not be necessary if chemical methods are used.

  • Fire Retardant Preservative- This treatment is intended to protect materials against fire as well as decay and insect attack. A mixture of boric acid / copper sulphate / zinc chloride / sodium dichromate in a ratio of 3:1:5:6 is recommended at 25% for indoor and outdoor use

  • For Termites- 1% Dieldrin may be added to the preservative. However, Dieldrin is dangerous, and use is illegal in several countries.

Further information
• Non poisonous Timber Protection Practical Action Technical Brief
• Designing and Building with Bamboo by Jules J. A. Janssen

https://www.guaduabamboo.com/preservation/chemical-bamboo-preservation

https://www.guaduabamboo.com/preservation/durability-of-bamboo

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Bambusa Tulda

Bambusa Tulda ( Also called Jati, Makor, Makol, Mirtinga, Wati, Owati, Koraincho, Longmeli, Rawthang, Mritanga etc.) is one of the most important species of bamboo.

Bamboo is called the poor man’s timber and India is one of its largest habitats. It is a fast growing species. Ironically classified as a NON TIMBER FOREST PRODUCT, its wood quality is better than any of the hardwoods. It matures in a short period of 3 years, thus also called GREEN GOLD.

I surveyed the viability of including Bambusa Tulda as an agro-forestry crop for Tarai Area to cater to my requirement of a suitable raw material for handicraft industry. Unfortunately, I found it too hollow and its diameter too little to cater to my requirement, and thus I have shelved the idea.

Nevertheless, as a matter of record, I am enlisting certain pertinent findings from what I read and saw.

Bambusa Tulda naturally occurs in parts of N.E India and naturalized in Iraq, Puerto Rico, and parts of South America. It is a tall tropical bamboo, with a long period of vegetative growth. Culms are about 17 to 22 m high, dia about 3 to 6 cm ( 1 to 2 inches),  usually straight, bright to dark green, with streaks of yellow. Wall thickness is around 0.5 to 1.5 cm. It grows well in moist hilly tracts of N.E India and has its applications in basketry and woven handicrafts. It is a good raw material for paper industry.

As per Wikipedia

Young culms are green, which turn greyish green on maturity. Young shoots are greenish-yellow, with a powdery top. Culms are covered with white blooms. A band of white hairs occurs above the nodes. Branching occurs from the base to top. Aerial roots reach up to few nodes above.
Culm sheaths are triangular with a conical blade, and straw-colored. The sheath proper is asymmetrical and 15-32 cm in length and 25-34 cm wide. Blade length is 5-10 cm. Auricles are unequal where the large one is rounded and situated on the side of the blade. The upper surface of the sheath is covered with blackish-brown hairs. The lower surface of the sheath is not hairy. Sheaths fall off early

Other Sources-

http://tropical.theferns.info/viewtropical.php?id=Bambusa+tulda

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Iron Bamboo- Thyrsostachys Oliveri- Kanak Kainch

Thyrsostachys Oliveri, another of the few "Iron Bamboos", is native to the Thailand, South China and N.E India (Tripura area). It is one of the most important bamboo species, because of its near solid structure and fiber quality. Locally called the Kanak Kaich, its a fairly straight growing mid sized bamboo, with a small spread. Farmers in Katlamara in West Tripura cultivate this bamboo at close spacing of about 2.5 m x 2.5 m.

I found this IRON BAMBOO species interesting, due to its vigorous growth at a Nursery close to Dehradun. I have, thus planted a few in my little bambusarium, due to its possible applications in the handicraft sector.

Thyrsostachys oliveri is a short rhizomed, perennial, evergreen, clumping/sympodial tropical bamboo, with persistent culm-sheath, which is an identifying feature.

thyrsostachys oliveri consistent culm sheath

The almost straight/erect culms are about 15 - 25 m long; 50 - 70mm in dia and about 40 - 60cm internode.

Thyrrsostachys_oliveri

As an iron bamboo, its valued as an excellent material for house-beams and miscellaneous applications in construction. The culms are used for reinforcing concrete blocks. Local craftsmen use this bamboo for handicrafts- mat-making, basketry, broom handles etc. Its fiber has a dark brown lustre, which makes it a material of choice for handicrafts. In Thailand, the young shoots are harvested for the production of steamed bamboo shoots.

Habitat : This species originates on the low hills forest, open areas at an altitudinal ranges of 500–700 m.

Distribution : Thailand, Myanmar, China - introduced and cultivated in tropical / subtropical Asia (Gamble, 1896; Wu, 2006).

Silvi-cultural management techniques Propagated through air-layering, culm cutting or offset planting.

Local Names :

Thailand;Phai ruak dam

Burma-Thanawa. Thyrsostachys Oliveri is a Native of Burma. (Nayagarh & Ganjam Districts)

Manipur- Keirakwa

Tripura- Kanak Kaich, Busai, Nusai, Nala Bauns

 

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Bamboo Trails- Dendrocalamus Stocksii

I learnt about this near solid, iron-bamboo (Dendrocalamus Stocksii) from an article published by Institute of Wood Science and Technology. The interesting feature was its loose-clumping growth habit, along with a near absence of inter-nodal cavity, thereby making it a suitable candidate for consideration of use to replace wood in certain applications in the handicraft industry. Also alluded to, as an iron-bamboo due to its iron like strength, this species is practically non-existent in N. India. Scientists at FRI and various agricultural institutes need to study the viability of introducing Dendrocalamus Stocksii in the TARAI, which is pretty humid and moist, much like the costal area, where this bamboo is naturally found.

Classification

Dendrocalamus stocksii (Munro), synonym Oxytenanthera stocksii / Pseudoxytenanthera stocksiiaabsence (Munro), synonym Oxytenanthera stocksii / Pseudoxytenanthera stocksii

As per the alluded article, Dendrocalamus stocksii is naturally distributed in Central Western Ghats. Locally called - Chivari’, Mes, Konda, Oor-shema, Marihal, Manga etc. D. stocksii has medium sized, stout solid and strong culms. Though the natural distribution of this species is in humid tropics, this species has a wide adaptability and comes up well in tropical humid, sub humid and semi-arid conditions.

MORPHOLOGY

Culms are said to be about 8 to 9m, basal dia 25-58mm and internode of 15-30cm, light green in colour, loosely spaced and without thorns. They are solid at the base upto about half the culm height.

Anatomical and Mechanical Properties of Dendrocalamus stocksii

Specific gravity- 0.691

Fibre Diameter (μm)- 16.6

Fibre Lumen Diameter (μm)- 5.7

Fibre length (mm)-3.4

Fibre Wall Thickness (μm)- 10.9

Modulus of Rupture (MOR) (kg/cm2)- 620

Maximum crushing stress (kg/cm2)- 386

Vascular bundles per cm2- 281

(Source: Rao et al., 2004)

Species Specific gravity MOR (kg/cm2) Max. crushing stress (kg/cm2)
Dendrocalamus stocksii 0.691 620 386
Bambusa nutans 0.603 529 456
Bambusa bambos 0.584 836 572
Dendrocalamus strictus 0.631 734 359
Tectona grandis 0.604 959 532
comparison
kN/cm²   spruce   bamboo   steel St37
elastic modulus   1100   2000   21000
compressive compressive   4.3   6.2-9.3   14
tension strength   8.9   14.8-38.4   16
bending strength   6.8   7.6-27.6   14
shearing strength   0.7   2.0   9.2

Source- http://bambus.rwth-aachen.de/eng/reports/mechanical_properties/referat2.html

The compressive strength of bamboo is roughly situated between 40 and 80 N/mm2 which is twice to four times the value of most timber species. Bamboo with low moisture content has a higher compressive strength than one with higher moisture.

The shear strength of bamboo is often twice the value of popular timber species.

The bending strength of most bamboo species varies between 50 and 150 N/mm2 and is on average twice as strong as most conventional structural timbers

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