I’ve been making guitars for a long time. My approach to the selection of the topwood (which is commonly agreed on as being the soul of the guitar) relies on a favorable stiffness-to-weight ratio — more so than on the grain’s evenness, count, or color. The wood’s weight is critical to me: it’s half the formula. I’ve sorted through uncounted topwood sets in the last forty-plus years and the range of their densities has never failed to impress itself on me. The same has also been true of the many piles of spruce and cedar planks I’ve sorted through and made selections from. I’d handle planks that were so heavy that they seemed fresh-felled and still full of water; they’d be next to planks that were so light that you could sneeze and they’d practically blow off the pile. These woods were of comparable size and had been kiln-dried together, so the moisture content would have been the same. I assumed that this disparity was all normal and natural — but it was only recently that I’ve learned of one of the mechanisms by which Nature produces such variety. I came upon an article written by Ernst Zurcher (with an umlaut over the “u”), a Swiss forestry expert, that explained how wood retains different weight, durability, and working properties when it is felled in synchrony with various phases of the moon.
That article is titled “Lunar rhythms in forestry traditions: lunar-correlated phenomena in tree biology and wood properties”. Zurcher wrote it for Wood Sciences magazine, HG F.21, c/o the Department of Forest Sciences, Swiss Federal Institute of Technology, Zurich, ETH-Zentrum, Zurich CH-8092, Switzerland (email: firstname.lastname@example.org). Zurcher, it turns out, has written extensively on this fascinating topic.
Zurcher’s article, focusing as it does on the matter of timing in tree-felling practices, gave me an insight into the variation in woods’ mass that I’d long noticed. Traditional European forestry practices depend on a mindset of selectivity that is not possible for modern commercial lumbering businesses to even consider: these clear by the acre or square mile, and certainly not only during certain phases of the moon. European woods that are purposefully felled in relation to the moon’s cycles are in fact called “full moon wood”, among other things. Somehow, I seem to want to call this material “werewood”. I’ve also discovered, since reading Zurcher’s article, that there are lots of people who know about such wood and have known about it long before I did.
Regardless of what such wood is called, Zurcher’s thesis is this: Since before the time of Christ, foresters have noticed that the woods they cut yielded different working and stabilizing properties, in direct correlation with where in the lunar cycle those woods are felled. Woods cut during the full moon, the new moon, or the waning moon, have consistently different characteristics. Therefore, a number of especially advantageous uses for timber could be correlated with specific felling dates. [NOTE: Technically, proper assessment of felling dates also includes the moon’s cycles of height-trajectory with respect to the earth’s horizon, which shift from high to low and back again during the lunar cycle. Also, besides the phases of the moon and its height-of-travel over the earth’s horizon, the practice of paying attention to the felling date of a wood has also included which sign of the Zodiac was dominant at the time. Wood-cutting practices in places as diverse as Bhutan and Mali follow these “rules”. No, I’m not making this up; read the article.]
Zurcher points out that this body of empirically collected wisdom applies to a range of practical wood uses as diverse as house construction, roof shingles, wooden chimneys (well, they had them in the old days), barrels for storing liquids, boxes for storing foodstuffs, fuel (firewood), plows, transportation of felled woods via river floatation, and even musical instrument soundboards. Furthermore, the general rules for felling woods seem to be very similar across the continents. Whether in the Alpine regions, the Near East, in Africa, India, Ceylon, Brazil, and Guyana, these traditions all seem to be based in matching and independent observations. Zurcher quite reasonably points out that in the past, people had more time and more peace and quiet in which to observe how things work; indeed, such knowledge would have been vital to them.
Interestingly, while the empirical knowledge gotten through centuries of hands-on forestry practices has necessarily resulted in a body of oral tradition, peasant wisdom, and folklore, there’s also a significant body of historical writing in which lunar rhythms (over and above the cycles of the seasons) are mentioned as having an influence on the growth, structures, characteristics, and properties of plants. For instance, the Roman statesman and writer Pliny had advice to give on tree cutting, as well advising farmers to pick fruit for the market vs. fruit for their own stores at different phases of the moon: for the former, fruit picked just before or at the full moon would weigh more; for the latter, fruit picked during the new moon would last better.
The variations in wood density that I’ve mentioned noticing make sense within the context of modern vs. traditional wood felling practices. Today, loggers will work a forest, stand, or acreage indiscriminately, until their quota is met. The job might take weeks or months. But then, leaving a denuded hillside, they’ll move on to another patch of land and do the same. Selectivity is per acreage and tonnage, set by commercial considerations and not per specific intended use of the wood harvest. This contrasts sharply with the traditional selectivity that would have been the rule in any aware, non-industrial community of foresters: you go in and select a limited amount of wood to be used for specific purposes; you don’t cut indiscriminately and ship out by the lumber-truckfull. You take what you need, until the next trip into the forest. It’s easy to understand that these different mindsets would include or exclude ancillary, contextual, environmental, meteorological, commercial, and/or scheduling concerns.