Is it true that the most reliable tree-ring width measurements can be obtained only with the help of sophisticated microscope-aided measuring equipment?
top It has been said and written somewhere that direct measurement of the tree-ring widths on the top plate of an instrument by means of a machine that moves step by step the instrument itself under a micrometric ocular of a microscope, with a reading precision of a thousandth of a millimeter, should be the operating procedure of choice giving the most accurate results. It could be true provided that width of the rings were exactly constant along all the height of their section. Actually, the width of a ring can vary even of a millimeter (1000 thoudandths !) in the range of a few millimeters of the section height, as it can be seen in the photograph of a transversal section obtained by coring the trunk. But this is not our case, as the sections of the rings in a top plate of an instrument are radial. Furthermore, as it can be seen in the photograph, in a radial section the boundaries between the rings are usually very badly defined, not so well as in a core. Then the question is. What
