Not sure of the origin myself but I am aware that this tough oakleaf originated in the humid gulf states (southeastern states) and it has been for sale in several mail order nursery companies.

I just ran across a comment on another website that gives some background on the 'Ellen Huff' reference. Unconfirmed, of course.

"Mrs. Ellen Huff made this selection while living in Warner-Robbins, GA. She brought it with her to Satsuma, AL and proceeded to propagate it with dormant wood cuttings under her azaleas over winter. The bloom time is long and the plant is very durable and hardy."

That is correct. She was my mother-in-law and I was gm for Tom Dodd Nurseries. Somewhere on the web is her picture with my daughter Abby standing in front of 'Ellen Huff'