Anagalis arvensis* /Primrose Family
This plant was only about 4 inches tall, I almost missed it blooming along the Haw Ridge Greenway trail. It was blooming in mid-August. This plant is in the Primrose Family. The flowers start to close when the relative humidity reaches 80%, it was once used as a "poor man's hygrometer" in Europe. Some flowers close to protect their pollen from being washed away by rain.
Where seen: Oak Ridge Greenways, Haw Ridge Greenway, Warrior's Path SP