Tamed casteroids are one of the best wood getters. The most effective way is to hold it with a argy and go flying in a forest. The casteroid will get wood by itself. They can also be used as a better smithy if u pump their weight bc there is no slot limit so u can fit more stuff in it. It is also mobile which is great bc u can't pick up vanilla ark smithys in addition they also lower the weight of wood in their inventory making able to carry more. Also in the wild they are neutral unless u raid their damns which are great for getting rare flowers, cementing paste, silica pearls, and wood in which case they will attack u.
How to build dam farm:
12 foundations (preferably stone)
12-24 doorframe (preferably stone)
1)find an already existing dam
2)build a 3x3 box around the dam with fence foundations
3)place doorframe on top of the foundations;if the dam is underwater, put enough layers for the top doorframe to be out of the water
4)using an argie, pick up 2 to 3 beavers and drop them into the box. 2 is the minimum number needed for them to spawn a dam but I find that 3 works better. (note:if you want more dams, bring beavers from another spawn location as no more beavers will naturally spawn in that area. Its also preferable to build another box so they don't end up pushing each other out the top)
Dams will spawn around every 12 hours
Remember to not leave the items you don't want in the dam. Drop them so that the beavers can spawn a new one without having the dam demolish after a week.