From the CO2Science.org archive: CDN has entered the Ivy League. Which isn’t the bragging point it used to be as wokeness undermines the integrity of higher education. But no worries, for Harvard or us, because we’re only reporting on English Ivy, that hardy evergreen vine that adorns all the prettiest building in Merry Olde England and Merry Newe England too. From 1985 to 2006 there were three experiments showing that an extra 300 parts per million CO2 over an entire growing season or longer boosted ivy growth by an average of 66%, whereas 600 parts per million for an unidentified but presumably shorter amount of time boosted its growth by an average of 29.8% and an extra 900 parts per million over an unidentified interval boosted its growth by 25%. Which sounds to us not just like diminishing marginal returns but negative returns. Rather like the modern Ivy League itself, come to think of it.