Trilliums. I'm used to thinking of Trilliums as being rare, but they are actually quite plentiful. They just don't last very long and they only come once a year. Also, they grow in the woods and are not easy to spot from a moving car on a busy road. I've lived here for more than a year and have never realized how many trilliums there are, growing just a few yards from my house, I guess because if you want to see them you have to be willing to tromp around the woods in the rain wearing muck boots.