it's a very hard place to hide evidence. >> near the windshield wipers, dr. bock found bits of mountain grass and some unusual pine needles, neither of which was common in the area. >> it was material that had come from approximately 9,000 feet elevation in a canyon along the front range. >> this vegetation was consistent with the type growing near left-hand canyon. >> the car had been in the mountains, and it certainly fit the crime scene vegetation. >> and there was even more evidence natalie's car had been to the crime scene. >> natalie's car had three different types of tires on it, three completely different tread patterns on her car. >> those same tire impressions were discovered not far from natalie's body. and the entire right side of natalie's car was scratched.