October 16, 2003

Balsa wood

Everyone's seen it, a piece of incredibly lightweight balsa wood, maybe at a craft store or hobby shop or perhaps in one of those hand-tossed gliders or rubberband powered planes we played with as kids.

But what do you know about it?

The small country of Ecquador on the western coast of South America is the primary source of model grade balsa in the world. The scientific name for balsa wood is ochroma lagopus. The word balsa itself is Spanish meaning raft, in reference to its excellent floatation qualities.

There is no such thing as entire forests of balsa trees. They grow singly or in very small, widely scattered groups in the jungle. For hundreds of years, balsa was actually considered a weed tree. Each tree produces thousands of seeds which are scattered by the wind. Wherever there is an opening in the jungle canopy, made either by a farmer or by another tree dying, balsa will spring up as thick as grass. A farmer is often hard put to keep his food plot clear of balsa.

Balsa trees grow very rapidly (like all pesky weeds). Six months after germination, the tree is about 1-1/2 inches in diameter and 10 - 12 feet tall. In 6 to 10 years the tree is ready for cutting, having reached a height of 60 to 90 feet tall and a diameter of 12 to 45 inches. The basla leaf is similar in shape to a grape leaf, only a lot bigger. When the tree is young, these leaves measure a much as four feet across. They become progressivly smaller as the tree grows older, until they are about 8 - 10 inches across.

Nature evidently designed the balsa tree to be a "nurse tree" which would protect the slower-growing species of trees from the scorching jungle sun during their critical early years. For instance, in an area of the jungle that has been ravaged by a tropical storm or other natural disaster, the balsa trees will quickly sprout and begin to shoot up to impressive heights in a very short time. Their fast growth, and the extra large leaves they have in their early years, provide shade to the young seedlings of the slower-growing forest giants. By the time the seedlings are established enough to take care of themselves, the balsa tree is beginning to die.

The secret to balsa wood's lightness can only be seen with a microscope. The cells are big and very thin walled, so that the ratio of solid matter to open space is as small as possible. Most woods have gobs of heavy, plastic-like cement, called lignin, holding the cells together. In balsa, lignin is at a minimum. Only about 40% of the volume of a piece of balsa is solid substance. To give a balsa tree the strength it needs to stand in the jungle, nature pumps each balsa cell full of water until they become rigid - like a car tire full of air.

Most people are surprised to hear that botanically, balsa wood is only about the third or fourth lightest wood in the world. However, all the woods which are lighter than balsa are terribly weak and unsuitable for any practical use. Balsa wood is often considered the strongest wood for its weight in the world. Pound for pound it is stronger in some respects than pine, hickory, or even oak.

(excerpted from An Introduction to Balsa Wood)

Posted by Ted at October 16, 2003 06:55 AM | TrackBack

Also, this is a little known, but true fact. Near Steamboat Springs CO., a mountain man who ran a small variety store, was legally named "Balsa Wood". Although the origins of his name are unknown, he made a mean chili.

I believe he shared your same interest in this mostly overlooked, but quite useful type of wood.

Posted by: jim at October 16, 2003 11:39 AM

ROFLMAO I've been informed by oldest daughter that this is by far the most boring and stupid thing I've ever posted. I make a pretty good chili too!

Posted by: Ted at October 16, 2003 11:51 AM

And the evil capitalists at Guillow want to corner the world market. Fiends!

Posted by: Velociman at October 16, 2003 07:49 PM

Confusingly, balsa is classified as a hardwood.

Posted by: Pixy Misa at October 16, 2003 07:57 PM

Of course, the volume of the cells is the reason for it's growth rate as well as it's lightness, as it's metabolism may not be much differant from that of an oak.
It's kinda like a giraffe's neck. It has the same number of vertebrae as any other mammal, they're just really big-ass vertebrae.

Posted by: Tuning Spork at October 16, 2003 08:58 PM

lol. its not boring.

Posted by: jim at October 17, 2003 07:53 AM

i'm a owner of an enterprise who deals with enrichment programs for kids, one of them is "aeromodeling"
i purchase thoushands of balsa sheets in a year
i found your website appropriate and i want to know if the prices i got till now are interesting for you to be our only suppliers
we buy sheet of balsa in about this prices:
5 m"m for 0.5$ each
3 m"m for 0.3 each
1.5 m"m for 0.2 $ each
+ freight cost (via sea)
let me know if it's interesting you
we can also serve you as a representative in israel

Posted by: oren chen at October 24, 2004 03:33 PM

i live in new zealand, and am interested in 1. growing balsa, and 2.getting some larger bits, square or rectangular, about 40 to 100mm * 40-100mm and up to 500mm long.
does anyone have any ideas??
any help much appreciated.
ps. i love chilli.

Posted by: james at December 2, 2004 10:29 PM
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