Re: top 10 yuccas. HEY TIM....
You can grow any but the most tropical species in 8a NC. I'd recommend aloifolia, treculeana, faxonii and rostrata for trunking species. Depending on what your dirt is all but rostrata should make good in it. Rostrata will require built up well draining soil unless you're at the beach or on a sandhill. In that case even that species can go right in the ground. If you're interested in log growing species I'd recommend Yucca filimentosa concava. You have quite a few agave secies you can grow along with many other genera of agavacea.
Don, SE, NC, 8a