K is for Kiri

Paulownia tomentosa, of the Scrophulariaceae family.

This small Japanese tree with the unfortunate family name has been grown in England as the foxglove tree. The very light (under 350 kilos per cubic metre) wood can look a bit like an exposed hard-wood cedar, silvery grey, or it may have a redder colour.

It is used in Japan for making kotos, which date back to the middle of the first millenium when they only had five or six strings. The contemporary 13 string koto is actually modelled on the Chinese Zheng, and as it came into being in the 8th century, probably is the first Jap copy to hit the market.

You may have encountered Kiri on a rather upmarket visiting card; it can be used to make a very thin veneer. The cards I've seen were actually rather vulgar kitsch.

K is for Kirsche, Prunus avium, of the Rosaceae.

I thought you might enjoy the German name for wild cherry, which grows right across Europe (Kers in Holland), in Scandinavia and Russia, North Africa and Asia.

Alcoholic associations aside, it usually gives a straight grained fine textured wood, over 600 kilos per cubic metre, which is as tough and strong as oak. It turns a lovely red when polished, but is not in constant supply. You might see it inlaid as decoration in a very arty harpsichord or piano case, or supplying colour in a fancy classical rosette.

K is for Koa, Acacia koa, family Papilionaceae.

This Hawaiian timber (rich brown, sometimes curly, sometimes long-grained) first drifted into the States with Hawaiian bands earlier this century. C.E. Martin used it on guitars between 1917 and 1935, and I tried a little Koa back and sides one belonging to John Pearse. It looked and sounded like a cross between mahogany and rosewood, combining rosewood warmth with mahogany clarity and projection — a surprisingly powerful little instrument, and very attractive.

The Hawaiians got a bit sniffy about having their indigenous timber carted off, and banned its export, but back and sides sets can still be got with difficulty. David Dyke has some available occasionally, via an American who he believes probably barters part worked timber with a Hawaiian. He describes the texture as fine and close, but with some long pores that may need filling, and rather heavier than Honduras mahogany — my guess would be well over 600 kilos per cubic metre. Quality is quite variable, however, flaming and figuring — fetching a higher price than plainer stuff.

Maker Ralph Bown has just used some to make a 31in scale baritone guitar (a fifth down, overall) for Martin Simpson, and he says it was very difficult to work, tending to bend in facets on the iron, easy to break (flame stuff very difficult to plane, figured stuff a pig), can't scrape it... It seems he had a hard time. He described the weight as somewhere between mahogany and rosewood.

As this is hard to get, serious enquiries only to David Dyke on (Contact Details). Ralph Bown is on (Contact Details). Short supply might make Koa seem over-priced, but if you want that particular tone and are very fussy, I guess you just cough up.