Senecio aureus or Packera aurea
Blooming now, April through May, is Senecio aureus, or Golden Ragwort! The flower stalks of this spring wildflower can grow 12 to 30 inches in height, towering over a low, spreading groundcover of heart-shaped leaves. Each of the basal leaves is bluntly toothed and has a long stem, or petiole. The underside of the leaf is purplish in color.
Golden Ragwort is another member of the composite family, Asteraceae. In this species, multiple flower heads create an airy spray of color floating on wispy stalks; both the ray flowers and the disk flowers are brilliant, golden yellow. The leaves on the flower stalk are quite different from the basal leaves: they are small, alternate and finely dissected– almost fern-like. Click on the photos below for a larger view of the leaf morphology.
Historically, all of the species in the genus Senecio had medical applications for home-use. Golden ragwort was used to treat a number of uterine maladies in women, hence the other common names for the plant–Squaw Weed and Life Root.
It is not uncommon to find very large patches of this plant in bloom on the forest floor, just before the trees leaf out. Golden Ragwort produces a welcome splash of spring color in the otherwise drab late-winter to early-spring landscape.
There are other ragworts in our area. Read here about Roundleaf Ragwort.
VIRGINIA WILDFLOWERS 
I purchased one plant of golden ragwort three years ago. It is planted in soil that is damp. It has multiplied quickly to the point I would call it invasive. I think I will pull it all up. It is nice to have the yellow flowers early in the spring, but I am worried that it is not manageable.
I know what you mean! I’ve seen it spread extensively in the woods. On the other hand, if it is contained in a specific area, it really is a nice source of color early in the season when nothing else is in bloom yet.
It is an early Spring lawn flower in my lawn…along with the ranunculus and purple and white violets…we postpone first Spring mowing to enjoy these.