Typically 2 or 3 balsa trees per hectare of natural SA rain forest, whereas plantations easily manage 1,000 balsa trees/hectare in a monoculture with less than 10 years planting to harvest. 60% + (volume wise) of balsa in commerce is plantation grown as of 2023.

Yes, there is a wide variation in balsa hardness. Most of the stuff in hobby stores for model airplanes and the like tends to be the very softest pieces.

Eric Meier, first published April 9, 2009

Who is the author of this article and when was it published? thank you

No, it is not isotropic. MOE is almost universally listed as longitudinal value unless otherwise noted in literature.

Common Name(s): Paulownia, Royal Paulownia, Princess Tree, Kiri
Scientific Name: Paulownia tomentosa
Distribution: Native to eastern Asia; also planted in eastern North America
Tree Size: 30-65 ft (10-20 m) tall, 2-4 ft (.6-1.2 m) trunk diameter
Average Dried Weight: 18 lbs/ft3 (280 kg/m3)
Specific Gravity (Basic, 12% MC): .25, .28
Janka Hardness: 300 lbf (1,330 N)
Modulus of Rupture: 5,480 lbf/in2 (37.8 MPa)
Elastic Modulus: 635,000 lbf/in2 (4.38 GPa)
Crushing Strength: 3,010 lbf/in2 (20.7 MPa)
Shrinkage: Radial: 2.4%, Tangential: 3.9%, Volumetric: 6.4%, T/R Ratio: 1.6

This is a real serious site about woods. Thank you, Erick, for your dedication and compilation of data. Allow me to say, without being condescending, You are the guru of the gurus.

Hope this helps you Dhyana.

Not too many things fall out of the sky unscathed. As far as the wind breaking models to pieces, construction is rated, windspeed has a cap, even before flight, and there is always pilot error.

Yes, balsa was chiefly used as the material for small toy gliders and model crafting, including planes.

Balsa isn’t very strong, but its low density makes it an excellent core material for composite structures.

Balsa has been the standard material for model aircraft for decades. Plastic foam materials offer better crash-resistance, but balsa is still used as a laminate core material in many high performance designs. The de Havilland Mosquito was built with balsa-cored plywood and proved to be one of the most vital combat aircraft of the Second World War. Many yachts are built with a balsa-cored fiberglass hull, which provides excellent strength and good thermal insulation. Balsa is used as a core material in many transit applications, because it is less flammable than most plastic foams and does not produce toxic smoke.

No, I am saying it is crappy because if you try to fly those model planes they will break to pieces from wind. There are plenty of wood essences much better from the POV of durability and just as light. I do not need a paper mache model airplane that can break from wind. I should be able to use any model I make. For instance telia wood is light easy to work with and much more resistant.

I’m sorry, but that’s just ignorant. Bala is an amazing wood for the right application. It’s unmatched for model airplanes (also used in ful scale airplanes to some extent!) in terms of lightness and workability. You shoudn’t say it’s crappy just because you don’t know what to use it for.