Read my last statement I said sure the mokuton would go out of control and would be useless I agreed with u but Madara is not becoming a tree the yang chakra only affected yamato's wood tech not yamato himself this is enough proof Madara will not become a tree if he is close to naruto
@ bold read the above statement
Lastly Zetsu as I said is basically a plant I don't think he is a good example.
Zetsu was made from Hashirama's cells using plant as a medium yes, but a plant is not a tree and grass is not wood.
Naruto does not turn everything that is alive into a tree, he does not trun grass into trees, he turned zetsu into a tree because of Hashirama's cells.
It's not about him being a plant, Danzo could not control the yang chakra because it was so great, which resulted in him being turned into a tree.
If the yang chakra that is already in madara is balanced, and Karuma's own yang chakra causes the yang chakra to be substantially more abundant the Motokun will overwhelm Madara, Madara will be affected because he has Hashi's cells within him, that means Yang chakra and Motokun.
The Motokun will get activated and overwhelm.
Why didn't this happen to Yamato?
1.Naruto had just started to master perfect Nin-Jin mode, hence less yang chakra release.
Yamato's chakra reserves are huge enough to power the zetsu army, so a very large amount would be needed and naruto was not tapping into this during his interactions with Yamato.
2. Yamato is different, he was injected with Hashirama's DNA shortly after his birth, all of the other subjects died except for Yamato.
From there on the way that Orochimaru has been trying to attain the power of the 1st has been different, he has been fusing Hashirama's cells with the subjects as opposed to injecting the DNA with into the body of the subject with the Hope that it would be accepted.