Hi, welcome to GoY, well it looks like a Yucca to me, but from the photo, can't tell which species, what colour are /were the flowers, this may help with identification, Derek.

If the leaves aren't sharp, then it would be Cordyline Australis and if this is the case then it will end up perhaps ten feet or more. You would be best to remove the lower dead leaves making a clear trunk.

Definitely a Cordyline. Yuccas have larger, more bell-shaped flowers.

My neighbour has one in their garden it has grown a lot taller over the years, it was bought as a Yucca but I too think it is a Cordyline.

The taller Yuccas are either too tropical to take cold winters, as in Y. elephantipes, or too much the desert hardcases to take prolonged wet, as in Y. brevifolia.