Why does Nottingham Forest have a red tree as its logo?

There are no red trees. Trees are green. Forests are green. I don't root for one thing colored red: not the Republican Party, not Manchester United. Well, I guess that's wrong, I do root for the "Heat". But overwhelmingly I root for things that are blue: City, Pitt, the "Dolphins".  Green should be Nottingham Forest's logo, hunter green, British racing green, a dark forest green. Not red.