From the CO2Science Archive: ‘Tis the season when we go boldly into the snowy woods with our axe in hand to cut down a Christmas tree, or more likely to the grocery store or shopping mall to buy one. Fir trees are popular specimens because they smell nice and have soft needles. Around here we usually get Balsam Fir or Abies balsamea, but this week’s entry is its taller European cousin Abies alba Miller or Silver Fir. And there doesn’t seem to be a downside to this tree: they are hardy, attractive and they produce sugar that attracts pollinators. So more good news, in that from 2000 to 2005 there were 5 experiments showing that Silver Fir seedlings grew an extra 33.2% when exposed to an extra 300 ppm CO2. So bring some Christmas cheer to a Silver Fir near you and emit a little extra CO2 while you’re out doing your gift shopping.