Talk:Shadow Play - Part 2/@comment-6411076-20190408185739/@comment-29981995-20190408195048

The Tree has its own magic even without the elements, as Celestia stated when she and Luna removed the elements in flashback in Princess Twilight Sparkle. However, after a thousand years of being attacked by Plunderseed vines the magic eventually grew too weak to hold them back. As a result, the Mane 6 returned the Elements so that their magic could repower the Tree, which destroyed the Plunderseed vines. Presumably that brought the Tree back to its original strength-if anything making it stronger-so that the occasional removal of the Elements would still leave it capable of maintaining order in the Everfree Forest.