
I am sad that it doesn't even get mentioned. Maybe it is hidden in some inconsequential NPC, but who knows? The Greenwrath is an interesting concept for roleplay and if there were more information about it in ARR we could use it more effectively. But right now, some things might or might have not been retconned, and some things might or might have not changed. It's hard to say.
Back on the subject of the Ixali: the Elementals seem to have a policy with those that live in the Twelveswood that asks them to return what they take from the forest. If you want to cut down 10 trees, you have to plant 10 new ones. I imagine other things would work like some kind of barter (because I'm not sure how you would return consumed food, for example). It's likely that the Ixali were breaking this rule in some way. The specifics of it can be assumed to have been lost to history and, if there's more than one version, we can pretend all of them are product of an in-universe lack of data about the matter.
Back on the subject of the Ixali: the Elementals seem to have a policy with those that live in the Twelveswood that asks them to return what they take from the forest. If you want to cut down 10 trees, you have to plant 10 new ones. I imagine other things would work like some kind of barter (because I'm not sure how you would return consumed food, for example). It's likely that the Ixali were breaking this rule in some way. The specifics of it can be assumed to have been lost to history and, if there's more than one version, we can pretend all of them are product of an in-universe lack of data about the matter.