Very tall perennial growing in South Georgia. NOT Hardy Sunflower like someone suggested. Yellow flowering all up the 10 foot stalk. Thick stalks with lanceolate, dark green leaves. Blooms October. Trying to help a friend identify this.

It is exactly like Helianthus maximilliani - a perennial sunflower, a native of North America that I grew before. I had to remove it because it bloomed so late in the fall that it was too cold to clean up afterwards.

Could be Helianthus angustifolius.

With you saying it is sticky to the touch it makes me think it might be rosinweed, http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=c438 &
http://www.nrcs.usda.gov/Internet/FSE_PLANTMATERIALS/publications/gapmcpu9008.pdf

As you can see though, Rosinweed's leaves don't match my visual. Thanks though.