Neither the first nor the second ability has a duration. If one of them resolves, it will remain in effect until Warden of the First Tree leaves the battlefield or some subsequent effect changes its characteristics.

The first and second activated abilities cause Warden of the First Tree to lose any other creature types it has. It retains any card types or supertypes it may have.

The first ability overwrites any previous effects that set the creature's base power and toughness to specific values. Any power- or toughness-setting effects that start to apply after the first ability resolves will overwrite this effect.

Effects that modify Warden of the First Tree's power or toughness, such as the one created by Titanic Growth, will apply to Warden of the First Tree no matter when they started to take effect. The same is true for any +1/+1 counters on Warden of the First Tree and effects that switch its power and toughness.