Please educate me about moonwood tops

[Michael Watts]

Moon-harvested Spruce, as the name suggests, is harvested at the phase in the lunar cycle where the sap of the tree is at its lowest. This is a centuries old technique.

I have played somewhere in the region of 40-50 "Moon Spruce" topped guitars. Some were great, some were not. This was due to who made them and how rather than any lunar properties...