Thanks for posting this. Interesting read.
...Kuniholm believes...that the Turkish pine, growing in a warmer climate and at a lower latitude, absorbed less carbon-14 during documented periods of so-called solar minima -- prolonged cooling periods in the Northern Hemisphere, such as those in the eighth and ninth centuries B.C. and in the 15th and 16th centuries A.D. The German oak, which starts its growing season later in the spring than does the Turkish pine, absorbed measurably more amounts of carbon-14 during such cooling periods. Also, the pines are not as efficient at photo-synthesis as the broad-leaf oak. Note the reference to "prolonged cooling periods."
I think over-specialization has become a problem in the sciences.