Looks like the Pinxterbloom Azalea to me. Also known as Rhododendron nudiflorum and Rhododendron periclymenoides. It is a native azalea that blooms in April.

In any case, it is a deciduous azalea. If it was dug in the wild, it is most likely native. Here are some possibilities:

It looks a lot like R. canescens, the Florida Pinxter or Piedmont Azalea.
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Canescens has white to pinkish tubular flowers with stamens two to three times longer than the petals. It is often confused with R. periclymenoides. Both are medium deciduous azaleas that are found in the Carolinas but can be separated by the flower tubes, which in R. periclymenoidesare fuzzy. R. canescens also has tiny hairs, but they are sticky and glandular. Another noticeable difference is that when a flower of R. periclymenoides dies, a ridge on the corolla tube tends to catch on the end of the pistil so that a flower cluster past its prime consists of several dangling blossoms. Although widespread in the eastern half of the U.S., these two wild azaleas differ in distribution. In South Carolina, for example, R. periclymenoides is a Piedmont plant, with almost no specimens reported from the Sandhills or Coastal plain, while R. canescens is predominantly a Low Country plant absent from the Piedmont, except in counties that border the Savannah River. In general, if it grows wild north of South Carolina, it's likely R. periclymenoides; south of the Palmetto State and it's probably R. canescens. Both species prefer moist, humus-laden, acidic soil but seem to do equally well in shade or sun. Old specimens can reach heights of 12-15 feet and have multiple stems or trunks up to 5" in diameter. Rhododendron canescens was discovered by Mark Catesby, who published a picture of it in 1731. Michaux collected it in South Carolina between 1784 and 1796. It was probably introduced to England in the mid-eighteenth century.

Here is a link that might be useful: Deciduous Native Azaleas