**I'm a new DM looking for advice on a potentially(?) problematic player.**

One of the players in our group consistently has their character run off.  She sees herself as "the wild card" and likes to break off from the focus of the rest of the party.  She even seems to enjoy when the other players become exasperated or frustrated with her. Occasionally this leads to fun or interesting scenarios, but it just as often leads to other players becoming frustrated or derailing the entire party to wander through the forest for half an hour with no particular reason or goal.

**An example:**

The party is traveling in the back of a wagon through a forest. The player in question is playing a druid character. She likes to roleplay the druid as being feral and animalistic, so she asks if she can smell anything interesting. I told her "You mostly smell the contents of the wagon, rations, etc. Outside is the smell of moist earth, trees, and fungus/rot."

Her immediate reaction is to jump out of the cart and run into the forest towards the rotting smell.  The other party members have to go into the forest after her.  This is one of the main problems they have. Because this player runs off, she becomes the *de facto* leader of the party.  The other players only have the options of either: 

 - Follow along.

 - Let her run off and end up splitting up the party.

After it was clear she wasn't going to turn back, I resolved the problem, and this worked fine for this scenario, but I don't really want to have to keep hedging players in by putting monsters and ambushes to the sides of the path. I want to let players be creative and explore.

If the whole party could agree it would be fine, but it seems to be mostly one character derailing everyone else. Then I have to come up with some scenario that puts her back on track with everyone else.