pf2e.fyi
From Pathfinder #202: Severed at the Root, which isn't enabled.

Quick Root

FEAT 5
UNCOMMON
Activity reaction
Prerequisites ardande trait, plant trait, or wood trait
Trigger A creature successfully Shoves or Trips you, or you fail a saving throw against an effect that would move you or knock you Prone.

You react instinctively, sprouting roots from your legs and plunging them deep into the ground to keep your footing. If a force would move you, you move half that distance, to a minimum of 5 feet. If you would be knocked prone, resolve the effect, then you Stand.

Special This feat gains the trait for your ancestry.
Pathfinder #202: Severed at the RootORC