Sprig of Yggdrasil

Rod, legendary (requires attunement by a cleric or druid)

The top of this wooden rod cradles a floating droplet of amber at its center. The rod itself is a splinter of the great world tree, Yggdrasil. While holding it, you are always under the effects of the barkskin spell, and whenever you deal damage with one of your cleric or druid cantrips, you can roll one additional damage die of the same kind and add it to the total. The rod can be used as a magic club that's always under the effects of shillelagh. It has 10 charges and regains 1d6 + 4 expended charges daily at dawn.

Spells. While holding the rod, you can use an action to expend 1 or more of its charges to cast one of the following spells from it, using your spell save DC: aura of life (2 charges), commune with nature (3 charges), locate animals or plants (trees only; no charges), plane shift (5 charges), speak with plants (trees only; 1 charge), transport via plants (4 charges), tree stride (1 charge), or wall of thorns (4 charges). This version of tree stride doesn't require your concentration, but it ends after you move through a tree with it.

Treant Form. While holding the rod, you can use an action to expend 7 of its charges to transform into a treant, as if by the polymorph spell, except you retain your alignment, personality, and Intelligence, Wisdom, and Charisma scores while transformed. This version of the treant doesn't have the Animate Trees action. The effect lasts for up to 12 hours. You can end the effect early using an action or if you're reduced to 0 hit points. While transformed, you are always under the effects of the aura of life spell, and any friendly creature that starts its turn within 30 feet of you gains 1d10 temporary hit points. You can reduce the number of charges you need to expend to transform in this way by 2 if you also expend a use of either your Channel Divinity or Wild Shape as part of using this property (no action required).

I can feel the roots of our world touching those of others. I can reach from one end of ours to another, like touching my hands together, because we're all the same entity.

(Psst, I didn't keep the bushy leaves in the end)