Back in the ancient past I took a course in dendrochronology at the UofA. The technique to measure tree rings is indeed tedious and time consuming. One thing I learned that is applicable to today, is that though there is a very good correlation between springtime moisture (the season when trees grow a ring) and tree ring width, there is much less of a relationship between temperature and moisture during the remainder of the year.
A wet spring may indeed mean lower temperatures during that time but says nothing about moisture and temperature the rest of the year. This is the fallacy of using tree-rings as an indicator of global warming by such as that charlatan Michael Mann, he of the “hockey stick” graph.
Ah yes, the UA Tree Ring Circus. Never did any of that stuff, myself.