If you look at the end of a felled tree, you will see the growth rings, known as annular rings, for obvious reasons. They circle out from the tree’s centre depicting the number of years the tree has been growing. Radiating out from the centre but perpendicular to the growth rings in a star-like pattern of small, faintly visibly lines known as medullary rays. They are very feint in some species and more noticeable in others. They are like fragmented, undulating sheets of silk flowing vertically up the tree in their radiating pattern.
If a plank that has a surface running parallel to the medullary rays, such as the centre planks, of the tree (see drawing in the wood cut section later) is planed and polished, these rays are clearly visible, prominently, in oaks, spectacularly with London planes and subtly with sycamores and maples. Each species has its particular charm when displayed in this cut. The cut is known as quarter-sawn and is considered to be the most stable cut, it also adds to the grain appearance.
In the case of oaks it is known as ‘silver’ grain and manifests itself as swirls and splodges of paler colours running across the grain. It is much sought after; if you catch a glimpse of the panelling at the Palace of Westminster, you will see how dramatic it can be.
The quarter-sawn planks of the London plane are so dramatically different to the normally very bland timber that it has a different title and is another example of a timber merchant’s silver tongue; they call it lacewood and double the price.