Thelesperma filifolium is the wildflower pictured here. It is a common roadside flower in many parts of Texas. The flowers pictured here show central disk flowers and 8 rayflowers which form the notched yellow petals. As you might have guessed, this plant in another Asteraceae family member. Greenthread flowers feed lots of different kinds of insects including honeybees. If you look closely, a pollen covered honeybee is in the central flower above.
Notice the unopened flowers in this picture and the green spike-shaped sepals beneath the flower bud. This character along with the very narrow leaves help distinguish this species from all the other yellow daisies you will encounter.
In the second picture, you can see the nodding flower buds and the thread-like leaves for which this plant is named. Their flowers are large, measuring 1.5 inches or more in diameter. They are generally found in clusters where conditions are favorable and sometimes you can find a field full of them. Their butter yellow color and brown disks are a beautiful springtime treat.