On 01/06/2016 6:40 PM, Electric Comet wrote:
On Wed, 06 Jan 2016 16:45:44 -0600
wrote:

A _given_ growth ring for a sequoia (or any other tree in the
temperate climatic zone) will absolutely _NOT_ span "decades". It'll
be in accord with the growing seasons which are, and have been for
the life of these trees, annual cycles.

fyi you are disagreeing with what dendrochronologists have determined by
careful analysis

In reality, _IN TEMPERATE ZONES_, the likelihood is that there may be an
additional ring or two now and then as OFWW notes may have occurred in
his region owing to an indication or dormancy and renewed growth again
more than once during the calendar year from an aberration from normal
weather patterns of sufficient magnitude and duration as to actually
cause the growth pattern to mimic another year. Similarly, particularly
in drier climates it's possible that a period of dormancy is caused by
drought that if relieved during the normal growing season may cause
another growth ring to be present that might otherwise not be.

It's also possible for there to have been an extended dormancy giving
rise to a missing ring for a given year; I'd posit that for such to have
been true for a period of decades is just not likely to be so albeit
there's a possibility that like in tropical regions the size of the ring
may be so small as to be essentially indetectable. I'd expect that few
specimens will survive such an instance if it were to have occurred at
which point it's pretty clear the next ring will span infinity.

Actual dating is done via statistical averaging of many samples and
normalized against alternative references to become absolute. There are
several established series internationally recognized that a given
specimen from an area can be compared against for such dating.

But, the possibility of a time span of "decades" between growth rings of
any of the common trees we in rec.woodworking would even know existed
and growing in NA or any similar temperate climate is essentially zero.

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