Black Pollen - South Carolina

I should know what pollen is associated with each species as a
Botanist, but I don't. The last few days the bees have
been collecting a dark brown - black pollen. Anyone know
what species of plant it is from?

I now live in Lancaster, SC. Technically about 2 miles from
Waxhaw, NC as the Russians fly.

Anyone want to buy a house in Baton Rouge, LA.
Lots of fruit trees.

For those of you who did not know, one of my customers who purchased some of my Russian nucs I sold him answered my question. Liriodendron tulipifera (yellow poplar or tulip poplar) produces dark brown to black pollen.

Thanks, James. I will be looking for that as a sign that our popular is getting going.