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.
These things are amazing! If you find a wild one, then that’s great because you can raid it’s dam for some cementing paste. Now, if you tame one, the beaver sadly won’t make any dams. But, you can now harvest a bunch of wood with it if you put it on wandering or use a saddle. If you think it’s a bit dangerous running on the ground, let me introduce you to one of the greatest things in this game for gathering, auto-harvest. Just get an argentavis and it’s saddle, grab a tamed beaver, and go up to a tree and let the beaver hit it. ( Put on wandering for the beaver for it to work) This is way safer than being on the ground. To get way more wood, put some levels into melee and even weight if you want to. Auto-harvest also works with ankylosaurus and doedicurus.
Seems to harvest more wood per hit than a mammoth, but the mammoth has better weight reduction, so just get your hairy-elephant to follow your splinter-mouse. Now admire the open plain where a proud forest once stood and laugh uncomfortably.