Dryad tree-dependence in combination with Liveoak or Awaken.

[RoSothian]

If the dryad's spirit was in a tree, I would think it would be very beneficial to her if she were to bring the tree to life. Then it could both follow her and extend the death range, and defend itself. It would very likely have to be a permanent spell, or refreshed every few days in the case of Liveoak.

I don't think the Permeancy spell can affect these spells, so what other ways can you give permanent life to an obedient tree? I'd say either find a treant already existing in the world or somehow grow a tree construct.

I'm not sure if dryads have access to such spells, but this is mostly for making them usable as a PC. This could also be applied to "half-dryads".

[Inevitability]

Awaken doesn't need permanency at all.

Also, since nonanimate plants are objects under D&D rules, you could cast Animate Objects and follow up with a Permanency. It is only useful if you don't have anyone able to cast Awaken, though.

[Ruethgar]

Also Acorn of Far travel explicitly works for a dryad and they only have an ECL of 4, so well within playability, though certainly not optimal. Furthermore, Liveoak and Greenwood items made from Dryad trees can count as their trees(I believe only explicitly with Liveoak).

[Mr Adventurer]

Also, RAW, a Dryad's tree does not radiate magic. This could be useful for concealing spellsor enhancements.

[Flickerdart]

Also, RAW, a Dryad's tree does not radiate magic. This could be useful for concealing spellsor enhancements.
It does not radiate magic as a result of being the dependent tree. That does not prevent it from radiating magic due to other reasons.

Also, I just noticed dryad SLAs are kind of weird - they can cast tree stride but immediately become ill if they go anywhere far. At least they have 3 uses of it per day, so they can tough it out and come back in the same day.