The tree guitar was made from a hollow section of silver birch, that was found during a forest school morning in nearby woods a couple of years ago. The tree had recently been blown down in a storm and the trunk still contained a lot of sap, so the first job was to char it out:
The first version of the instrument was an acoustic design, but it quickly became clear that the sides of the trunk were too thick to resonate and project volume. As a result, it was modified into an electric guitar using an under-saddle pickup which could be played using a blues slide, in the style of a pedal-steel guitar. However nylon rather than steel strings were chosen due to their lower tension, and the lower stresses this would create across the instrument.
Fitting the under saddle pickup and wiring in the input jack:
Stringing the guitar, using trusty La Bella 820Bs:
And finally, ready for action - the main riff of Gruffalo Blues which you can hear from the start of the song and underlying the whole track was played on the tree guitar. It was tuned in an open-D tuning again to reduce tension across the instrument, which is why the track is in D!