Geographical distribution

Bamboo, in all its varieties, is one of the most extensive and important botanical families for humans, with thousands of uses and applications described in different cultures. They are the only group of grasses adapted to creating forests and demonstrate enormous adaptability to different soils and environments. They occur naturally across a wide geographical distribution covering mainly three large regions: much of America, sub-Saharan Africa and a large area of Asia.

Fossils of bamboo leaves and pollen can be found in Europe, but there are currently no endemic species on this continent.

Growth and cutting

Some species of bamboo are the fastest growing plants on the planet. Varieties such as Guadua and Moso can grow up to 25 cm per day during the growth stage, but there are records of other species growing more than 1 m per day..

In just six months, the plant reaches its final height of 18 to 30 metres, and in the following years, the woody structure of the canes develops and they finish maturing.

This is one of the great advantages of using some varieties of this giant grass over the intensive use of trees, as in just four years it will be ready for cutting and use as structural material.

Among the wide variety of bamboos that exist, we carefully select the botanical varieties that stand out for their technical and sustainable properties:

Moso Bamboo (Phyllostachys edulis)

• Diameter: 5-12 cm
• Height: 15-20 m
• Uses: Decoration, flooring, laminated boards (most commonly used in flooring)

This is one of the most widespread families of bamboo in the world, partly due to its great ability to adapt to life in different environments, but above all because of its wonderful characteristics and uses. It is native to central China, where it has been an essential material in everyday life for thousands of years, and today it still grows in large virgin forests in the inland mountains. In spring, when new stems of a beautiful blue-green colour emerge from the rhizome, one can appreciate the impressive speed at which this bamboo grows, easily exceeding 30 cm per day.​

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Guadua Bamboo (Guadua angustifolia Kunth)

• Diameter: 5-12 cm
• Height: 20-25 m
• UsesUses: onstruction (renowned for its flexibility and seismic resistance)

This variety was initially identified as belonging to the Bambusa genus until 1822, when German botanist Karl S. Kunth determined that it constituted a genus in itself and identified it as Guadua, thus maintaining the term used by indigenous communities. Guadua is the most important genus of bamboo in America, endemic to this continent and comprising some 30 species. Guadua angustifolia, native to Colombia, is the most important of these thanks to its extraordinary physical and mechanical properties and the advances in silvicultural and structural studies that have been carried out in the country in recent years. Although it is found in its natural state from Ecuador to Venezuela and between 0 and 2,000 metres above sea level, the plants develop best between 500 and 1,500 metres, with temperatures of 17º to 26º, rainfall of 1,200 to 2,500 mm/year, relative humidity of 80-90% and moderately fertile, well-drained soils, characteristics of the central region of the Andes, known as the Coffee Region of Colombia.

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Guadua Bamboo forests

These bamboo clusters form what are known as bamboo groves, spectacular forests that are generally accessible as they are not particularly dense and give rise to highly dynamic and specialised ecosystems. They are home to a wealth of life, with a multitude of plants, mammals, birds and reptiles associated with them.

These groves are very important even in remote areas, as their main functions include regulating water flow, absorbing excess water and releasing it gradually to limit possible flooding, They prevent soil erosion and deforestation thanks to their underground branches, contribute a large amount of biomass to the soil and are one of the largest fixers of environmental CO2 on the planet, with records of between 100 and 150 tonnes per hectare in each life cycle, lasting 4 to 5 years.

Growth and cutting

Guadua does not increase in diameter over time, but emerges from the ground with its diameter already determined. Being a monocotyledon, it lacks cambium tissue and therefore does not grow thicker like trees... Depending on the type of soil and climatic conditions, these diameters can be up to 22-25 cm, although they are usually between 8 and 13 cm.

During the first 6 months, they grow protected by cauline leaves at a very high rate of up to 15 cm per day until they reach their final height of 20 to 30 m, with an intense green colour on the stem. Then the development of the lateral branches and foliage begins... over the following years, the plant will fix a large amount of environmental CO2, contributing biomass to the soil and developing its woody structure.

After about four years, the culm has a light opaque green colour, with evident presence of lichens on its outer bark. The stem is considered to be at the ideal maturity for use as structural material and is then cut. If this is done correctly (above the first node and without breaking it), a rhizomatic energy transfer mechanism begins in the plant and a new culm/rhizome begins to form, thus guaranteeing new production. Regular and controlled exploitation favours the development of the bamboo forest as a whole and stimulates its natural regeneration. It is estimated that the ideal composition of canes in a guadual is 10% shoots, 30% young stems, and 60% mature canes, with a density of 4,000 to 8,000 stems per hectare. The estimated productivity for a Guadua forest is between 1,200 and 1,400 stems per hectare/year, making it a totally effective alternative to wood for the production of structural laminates, boards, flooring, etc.

Guadua canes

Guadua stems, which grow to a height of over 20 metres, are cut into standard 6-metre-long canes, and depending on their original position on the plant, three different sections are established.

The canes obtained from the highest section, called Sobrebasa, have thin walls but maintain a high fibre content. They are used for auxiliary furniture, joists and battens.

The intermediate sections, or Basas, are slender and very light in relation to their enormous strength. They maintain their outer diameter very well and are very fibrous, making them the most commonly used pieces in construction, especially in the manufacture of beams and composite trusses.

The pieces at the bottom are called Cepas. They have thick walls, short internodes and, due to their high compressive strength, are perfect for building columns.

Immunisation treatment at source Guadua bamboo:

immersion in borax salts

o prevent the bamboo from being attacked by xylophagous insects and to prevent the appearance of fungi, the Guadua canes are immersed for 4-6 days in a solution of borax and boric acid in a 1:1 ratio and with a concentration of between 4 and 6%.

Before placing the canes in the solution, all the internodes of the canes are perforated. On the one hand, this greatly facilitates immersion as it allows the air to escape from inside the canes and the cane ceases to act as a float. On the other hand, it allows the mixture to enter the different sections of the cane, thus ensuring proper preservation as bamboo is much more permeable from the inside.

When perforating the diaphragms, one might think that we are reducing the load-bearing capacity of the cane. To determine this possible flaw, various studies have been carried out at the Technological University of Pereira in traction tests with perforated and unperforated stems, and the tests only show a decrease in resistance of around 2%, which is very insignificant compared to the great benefits provided by this preservation technique.

Preservation by immersion in pentaborate is considered environmentally friendly because, in addition to the fact that the pools are watertight and the solution is never released into the environment, its functionality does not depend on a toxic substance but on the morphology of the crystals that make up these salts. It is extremely common in detergents, fabric softeners and disinfectants as it is a natural product and harmless at these concentrations.

The mixture prevents the proliferation of insects without using poison thanks to the intrinsic structure of these boron salts (hard and angular), so that if a xylophagous insect attacks the cane, these small sharp stones pierce its stomach, preventing the insect from continuing its life cycle. As an added advantage, all materials treated in this way have fire-retardant or fire-resistant properties thanks to the borax solution.

Protection through Design and Maintenance

When building with bamboo outdoors (as with any wood), it is necessary to take into account the effect of the sun on the surface of the canes. Ultraviolet rays are highly damaging as they dry out and damage the surface, and can even cause it to ‘flake’.

For structural bamboo applications, whenever possible, it is preferable to prevent direct sunlight from hitting the canes by protecting the structure by design, including eaves in the project and not leaving the tips exposed.

Another important protection to consider is to avoid direct contact with sources of moisture because, although Guadua includes a complete anti-fungal and xylophagous treatment, large variations in humidity inside can end up causing cracks. This is avoided in structures by adding footings or some element that raises the piece and allows rainwater to drain away.

In Colombia, it is said that Guadua houses must include ‘a big hat and good boots’.

Regardless of this protection, to keep the guadua nourished, in good condition and looking healthy, we use oils such as those used for outdoor furniture. Today, there are many products on the market that perform this function well. The most important thing to keep in mind is that the oil should allow the cane to breathe by keeping the pores open (unlike varnishes or synthetic paints), offer high protection against UV rays while being water-repellent, and maintain a certain elasticity to prevent cracking due to possible variations in the shape of the cane. Using this type of oil makes maintenance very simple (new applications every year or two, without the need to remove the old material).

It is common for bamboo to develop cracks, always longitudinal, which do not pose any structural problems as the properties of the bamboo remain virtually unchanged. If it is necessary to hide these cracks, either for aesthetic reasons or to facilitate cleaning of the structure itself, the ideal solution is to cover them with the same flexible fillers used on wood, as it is common for the openings to close again with an increase in humidity.