No, this is not a story about anything holy. It’s about holly, the spiky stuff growing in many gardens and used as Christmas decorations. About 6 months ago I got a whole holly tree from a good friend. She had wanted to cut it down the previous summer, but after talking to me agreed to let it stand until the growing season was over, so it was finally taken down some time early December 2017.
I have now started looking into using the first few bits. If harvested in winter, most of the sugar content is gone from the sap in the tree, and as a result the wood turns out almost white, a much sought-after property. In addition, due to the slow growth, holly is quite hard (not when green), and it turns beautifully. It is an absolute pleasure to work with.
There are two severe downsides to holly, though. The first one is that it cracks like hell. The slightest knot or other disturbance of even grain, and bang, there goes the crack. These two little hollow forms were turned from green, and as you can see, I managed to get the wall thickness quite even. Nevertheless, the one on the left has developed this mighty cleft, and although the one on the right looks only warped to a high degree, I can tell you it has its cracks on the underside.
SO: green turning holly is not a guarantee to avoid cracking. And, at any rate, the warping is so bad that you need to leave extra thickness to compensate. Or you work to a finished surface from green, and accept that you will end up with highly oval bowls.
The second downside concerns the colour. When freshly cut, the wood is an ivory white, with a slight greenish tinge to it. This will last for a few hours, and the slowly turn into a darker colour. This is not a mould growing on the wood, it’s a checmical process caused by the exposure to oxygen and light.
This can be counteracted by immediately boiling the wood for approx. 30 minutes for every 10mm of thickness. However, that puts its own stress on the wood, and in reality: who can boil a 12″ bowl?
The colour change goes quite deep, several millimetres, and I have yet to find a way to prevent it. The only known way for it not to happen is to air-dry the wood completely and then work it. And that requires a lot of patience. No wonder properly dried, white holly is expensive.