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Can one determine which end of a plank taken from a tree trunk was pointing upwards as it grew?

鈥� This is often easier than might be expected. The grandstand at Lodge Park on the Sherborne Estate near Cheltenham, UK, was re-floored a few years ago with sweet chestnut (), often referred to as 鈥減oor man鈥檚 oak鈥�. To minimise waste, the planks were not cut to an even width. Instead, each plank followed the growth of the original tree, which tapered from ground level upwards. The tapering boards were then laid in alternating directions.

In this case, it was easy to tell which end of the plank had been pointing upwards. But even when boards have been squared up, the taper can still be detected in the wood grain, which converges towards what was the top of the tree.

Malcolm Nickolls, Aylesbury, Buckinghamshire, UK

鈥� On a macroscopic level the answer is yes, if you have a decent-sized spruce plank. This is because spruce branches always point upwards. Look at the end of the plank first 鈥� the curve of the grain will tell you which face was on the outside of the trunk.

Stand your plank up, then find a knot that runs right through it. Knots show where branches emerged from the trunk, so they will run from low down on the inside of the trunk to higher up on the outside.

Adrian Foulds, Glasgow, UK

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