Changestaff

This material  is Open Game Content, and is licensed for public use under the terms of the  Open Game License v1.0a.

Transmutation
Level Druid 7
Components V, S, F
Casting Time 1 round
Range Touch
Target Your touched staff
Duration 1 hour/level (D)
Saving Throw None
Spell Resistance No

You change a specially prepared quarterstaff into a Huge treantlike creature, about 24 feet tall. When you plant the end of the staff in the ground and speak a special command to conclude the casting of the spell, your staff turns into a creature that looks and fights just like a treant. The staff-treant defends you and obeys any spoken commands. However, it is by no means a true treant; it cannot converse with actual treants or control trees. If the staff-treant is reduced to 0 or fewer hit points, it crumbles to powder and the staff is destroyed. Otherwise, the staff returns to its normal form when the spell duration  expires (or when the spell is dismissed), and it can be used as the focus for another casting of the spell. The staff-treant is always at full strength when created, despite any wounds it may have incurred  the last time it appeared.

Focus The quarterstaff, which must be specially prepared. The staff must be a sound limb cut from an ash, oak, or yew, then cured, shaped, carved, and polished (a process requiring twenty-eight days).

You cannot adventure or engage in other strenuous activity during the shaping and carving  of the staff.