I've been training Woodcutting lately. I used two methods to get to 99. (I started my run at 92.) I would cut the evil trees, and then chop maples for the time that my logs are sent to the bank for me.
The other way was chopping Eucalyptus trees west of Oo'glog using Sacred Clay hatchets. I find it quicker to chop these than Yew logs, and less people around, do to the Level 69-99 Ogresses nearby. The logs sell quickly for 410 gp on the GE.