Yes that's true. Balsa wood is considered a hard wood.
While certainly not hard, for it's weight it is very strong.
It used to be used between sheets of aluminum for bulkheads in planes.
Don't know if it is still being used for that.

On 8/9/2010 2:21 AM, dpb wrote:
Martin H. Eastburn wrote:
Redwood is listed as a hardwood.
It is dense not porous.
...

"softwood" vis a vis "hardwood" is a generic differentiation of non- vs
deciduous, not a description of the wood itself. It is generally true
that hardwoods are, in fact, harder than softwoods on average but there
are exceptions.

I made no statement about density; nor did I infer it was particularly
an open-grained wood.

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