What is Balsa Wood?

manufacturing industry

The balsa wood tree, scientifically named ochroma lagopus, is a relatively fast growing plant found primarily in Central and South America. Balsa wood trees grow best under the conditions found in rainforests, ideally in mountainous terrain between rivers. The country of Ecuador is perhaps the largest exporter of balsa wood, although many local farmers consider the plant to be little more than a weed.

Balsa wood is one of the lightest varieties of wood available, but not the absolute lightest. Pound for pound, however, it is remarkably strong for its weight. Originally, the US military sought out balsa wood as a substitute for cork during WWI, but it soon proved more useful as a lightweight construction material for gliders and shipping containers. Hobbyists also began to work with balsa wood because it could be carved easily with standard woodworking tools and bent into a number of shapes without sacrificing strength.

Unlike some 'crop woods' such as pine, balsa wood cannot be grown in large groves or stands. Natural balsa wood trees propagate much like dandelions -- seeds are attached to soft tufts and carried off by the wind. If the seed lands in an area without direct sunlight, such as the dark canopy of the deep forest, it simply won't grow. A few lucky seeds may land in a sunlit patch or field and germinate, often to the chagrin of the farmer who owns the property. Balsa wood trees grow rapidly during their first five years, providing some shade to other plants with their oversized leaves.

The ideal balsa wood tree for harvesting is between six and ten years old. After ten years, the inner core of the tree begins to rot and the outer layers become useless. A balsa wood tree is naturally fortified by water stored in large cells. There may only be one or two balsa wood trees in an entire acre of land, so harvesting is usually performed by one or two native workers with axes and carving knives for bark removal. The hewn trees are carried to the river and bundled for easier water transport to the processing plant. Barges carry the trees all the way to ports in the United States.

Because raw balsa wood has such a high moisture content, it must be dried in a kiln for at least two weeks before it can be used commercially. The drying process creates an ultralight wood which is usually cut into sheets or round dowels. Balsa wood does have a grain, so consumers should be aware of what type of cut they need for a specific project. Some balsa wood is cut across the grain, which makes it suitable for carving but not for weight-bearing struts. Many of us may remember the toy balsa wood airplanes sold in stores, so it is easy to imagine how fragile balsa wood can be.

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14
I am a karate master and I use balsa wood to teach my students how strong I am at breaking!
- anon50802
12
what are the three types of balsa wood? and what are their characteristics?
- anon46081
11
Thanks for making this description it should help me great for my project.
- anon45540
10
this helped so much for my project.

- anon43681
9
balsa wood is actually a hardwood, it is the softest of all the hardwood, and super lightweight, around a 1/3 weight to strength of other hardwoods.
- anon31930
8
is balsa wood waterproof?
- anon23147
7
i use balsa wood all the time for school projects. this article was good help.
- anon21102
6
it's a soft wood... but very flexible and strong. as i said below, helpful for my topic.
- anon20682
5
Is Balsa wood a hard or soft wood?
- anon20087
4
the article is interesting, and helpful for my research on my project...:D

I wonder if the tree for the balsa wood is light weight too... but maybe not cause of the water and moisture... but what if you chop off a big big part of the tree, dry it in a kiln. will it be very light weight for its size like a ginormous piece of pumice?

- anon18082
3
What do balsa wood trees look like?
- anon11784
2
I remember the balsa wood airplanes - I guess I never really thought about them being made of actual wood because they seemed so light, almost like styrofoam. I would love to see the trees that make this amazing lightweight wood!
- dfrum32

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Written by Michael Pollick
Last Modified: 01 November 2009

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