Randy they keep to the yuccas only but any kind, from the bright edge to the spanish dagger, soft or strong, green or variegated.
The attack was at both end of the property and in between.
I wish I could know what kind of butterfly makes the deposit.
I did found on a few leaves the dried up shell of an egg.
I know which kind of bugs you have, I had them in VA....a pest to get rid of too.