Where does balsa come from?

After the Spanish conquered Central and South America, they discovered that light wood was used in logs for rafts already in the time of the Incas. The raft is called balsa in Spanish. The special light wood was thus named after its use and spread throughout the world.
Under the name balsa, every expert will remember that it is the lightest wood in the world, for which - due to its properties - no versatile substitute has yet been found even in lightweight (foamed) plastic materials.

The botanical name Ochroma lagopus, according to J.H. Pierce, includes about ten species of balsa, which are important for more detailed investigation from a scientific point of view. Ochroma lagopus belongs to the family Bombacaceae. Naturally found in tropical America, balsa is widespread from the Antilles and southern Mexico to Colombia, Bolivia and Peru. The most important country for balsa is Ecuador.

Balsa thrives best on the equator at an altitude of up to 1000 m, preferably from 100-500 m. Rainfall is suitable from 1250 to 3000 mm with a dry period of 2-5 months. The balsa tree is demanding on light, which precludes growth in a full canopy. Therefore, it grows in intersections and on the edge of dense forest, where it forms clear stands. It prefers soils with deep deposits and has the ability to adapt to sandy soils, where the depth of the soil is decisive. In view of these conditions, attempts were made to grow balsa in Java and Cameroon; no known results yet.

The growth of balsa is unimaginable for our conditions, which is shown by the table of average values:

age (years) height (m) average trunk heels (cm)
1 2 11
2 5 15
3 7 20
4 9 25
5 11 30
6 12 35
7 13 40
8 14 45
10 16 53
12 18 50
15 19 65

In favorable habitat conditions, trees achieve even better results. In 7 years, they can grow to a height of 20 m and a diameter of up to 80 cm, there are rare older trees 40-50 m high with a diameter of 80-100 cm. At about 15 years of age, balsa is in full development, but the wood is twice as dense (heavier) than that commonly used in the shop. That is why logs are mined earlier, the lower limit of mining is 6 years.

Balsa can be grown in a plantation manner, resulting in nice, straight and cylindrical trunks. There is no difference between heartwood and sapwood. Balsa is easily attacked by wood decaying fungi and insects. Freshly felled logs must be immediately stripped of their bark and transported to the river, from where they are floated on rafts to sawmills on the ocean coast. Procrastination in this processing phase causes the wood to turn red and deteriorate further. Logs are transported from the mining site using covers, the use of tractors is said to be uneconomical. Also, transportation by car or rail from the mining site pays off only when there is an increased demand for bales.

Considering that freshly felled logs weigh 300-400 kg and dry very slowly, the export of balsa in this yard is out of the question, which also speaks for the economical use of expensive ship space. The trunks are cut into relatively small prisms in order to shorten the drying time as much as possible, which happens naturally in the "pyramids" and lasts 2-6 months depending on the weather. The wood is sorted on the one hand when it is cut on feller saws (not at all modern), and on the other hand when it is assembled into packages for sea transport.

Balsa comes to the world market in two quality groups, which are designated as A and B. For quality A, only minor deterioration is tolerated, while for quality В there can be more deterioration and the wood is therefore suitable for less demanding use (e.g. for packaging ). In addition to these two groups, the so-called "light balsa" is also known in our country, particularly suitable for modeling purposes.

From the above, it follows that balsa wood by its very nature is very delicate, susceptible to damage and easily susceptible to various pests. Each log has more or less different technical properties, and even wood from different parts of the same log shows a difference much greater than that of other types of wood. Considering this, we can determine the factors that are of decisive importance for the quality of balsa wood:
a) age of the growth — wood
Trees felled too late (10-15 years) produce wood that is not suitable for our use. The most suitable age for balsa trees is from 6 to 10 years.
b) wood color
is directly dependent on the age of the wood. The darker the color, the more substantial the wood and, in principle, the older it is. In some cases, the darker coloration is caused by damage to the trunk.
The color of wood from different parts of the trunk is not the same. On the perimeter, the wood is young, light, the closer to the center and base of the trunk, the darker and heavier the wood.
c) trunk injury
causes abnormal growth and violation of the physical and technical properties of wood. It also allows the tree to be attacked by wood-rotting fungi and thus rot, which manifests itself as isolated nests in the wood or even continuous stripes.
d) timely removal of wood from the logging site
further processing is necessary to maintain good quality; it is here that damage by wood-destroying insects and fungi occurs most often.
e) weather conditions in the dry season
Under favorable conditions, the wood is of better quality and takes less time to dry, which again reduces the possibility of spoilage. According to reports, this year's dry season (June-October) has been favorable in Ecuador, so good quality timber is expected.

These are the main factors influencing the quality of balsa wood, which the trade and consumers cannot influence, but they must be known for purchase and receipt. External quality assessment is also influenced by the quality of processing blanks, which was not the best in the past, but is improving with the modernization of sawmills.

The use of BALSA is very wide due to the exceptional properties of this wood and is far from being limited to model making. The small specific weight directly predetermines balsa for life belts, rafts, buoys, etc.; Paraffin is used against water absorption. Due to its very good insulating properties (up to -250°), balsa is extremely suitable for refrigeration equipment and recently also for insulation in space bodies (it is already on the moon in American probes). It is also a very good electrical insulator. The use of balsa for packaging in air transport is extensive.

In the production of aircraft, balsa is used not only for fillings, but it has also proven itself as a structural material (e.g. the famous De Havilland "Mosquito" aircraft). There is no need to talk about the importance of balsa for model making. Balsa also plays an important role in the toy industry, in orthopedics and in fishing tackle. Use is also possible in the furniture industry, the production of cellulose and paper has also been tested. Balsa also serves as a substitute for cork in the production of linoleum, it is used for the filling of special skis and for many other purposes.

The largest producer and exporter is Ecuador, which covers 90-95% of world demand. The largest customer is the USA - about 90%, followed by England (8%), Australia (0.4%) and the rest mainly in Europe. The extraordinary interest of the USA at the moment is undoubtedly due to the war in Vietnam, where balsa is used mainly for packaging during the air transport of war material. This has the effect of constantly raising prices regardless of quality, and in the producing country it reaches the extreme that the price of "B" quality reaches the price of "A" quality. The current world balsv price is 30-40% higher than in the period 1963-1964.

Balsa is exported from Ecuador only in blanks of thickness 59, 72, 85 mm; 80 mm wide and 900 to 2500 mm long. Blanks longer than 1500 mm and of larger dimensions are 10-15% more expensive. The weight of the wood ranges from 150-170 kg per 1m3 at a wood moisture content of 15-20%. The prisms are packed in bundles with a volume of about 1/3 m3.

The total volume of balsa imports into Europe is not large compared to other wood, and therefore only specialized companies are involved in the balsa trade. The main importer is Drúnert from Bremen, which also supplies the USSR and Scandinavia.

The question may arise as to why we do not buy balsa directly in Ecuador and do so through an intermediary. There was such an attempt in the past, but the commercial and political situation thwarted it. In addition, economy is also decisive. Our purchases are small, only this year they exceeded 150m3. Therefore, relatively large costs for the processing of the market and all related matters would not be bearable. That is why it is more advantageous for us to buy in Europe and achieve better conditions with a one-time order.

The journey of balsa to your work table is long: from the forest or plantation and along the river to sawmills on the sea coast - from there already in bundles (often on the backs of workers) to small boats and ships - then to the European port and the warehouse of the importer. Transport to us is currently carried out by trucks. It is more expensive, but there is no need for translation and there is less deterioration. Afterwards, most of our balsa goes to woodworking shops, where it is cut into boards that you buy in stores.

The cutting technology is the same as for other wood, that is, classic cutting with a circular saw or band saw and the modern method - laser cutting. Most of the prisms are cut into boards with a thickness of 2-5 mm, while the loss through cutting reaches 30-50%. It is certainly worth considering both a more economical way of cutting and, on the other hand, the appropriate use of balsa sawdust, e.g. for a mushy filling material with the use of a suitable binder, as is already common abroad.

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