The MBH98 Corrigendum purported to explain the discrepancy of 35 series between the series listed in the original SI and the series actually used as follows:
These series, all of which come from the International Tree Ring Data Bank (ITRDB), met all the tests used for screening of the ITRDB data used in Mann et al.  (see Mann et al. (2000)), except one”¢’¬?namely, that in 1997, either it could not be ascertained by the authors how these series had been standardized by the original contributors, or it was known that the series had been aggressively standardized, removing multidecadal to century-scale fluctuations.
In this note, I show that these criteria do not explain either the exclusion of many of the 35 series or the seemingly inconsistent inclusion of series, which have been "aggressively standardized". For example, the Corrigendum exclusions include several Schweingruber series, even though many Schweingruber series are used in MBH98. More