We went and picked up our tree last week and my truck still smells like pine tree. That's what you get when you have a real tree though. I kind of like it. I wonder how long the pine tree scent will stick around?
We had the same situation, except the tree was inside our mini-van for an afternoon. We picked up the kids at school the next day, and that's the first thing they noticed. It's so wonderful to be a kid at Christmas.
When that tree smell goes away, visit your local auto store and pick up something to continue that smell. I use one of those under the seat jars with my favorite scent. That was there's nothing hanging from my rear view mirror.
One of the most festive car smells I ever ended up with was with I brought a small rosemary bush home. It was shaped like a Christmas tree and had bows on it. It rubbed against one of the seats. It smelled really nice for about a week.
This makes me want to go out and pick up some pine branches and drive around with them in the back seat. We spend as much time in the car as we do in the house, so why not have Christmas tree smell in there with you this time of year?