Sanseveria was widely planted near the coast in Martin County (Stuart) and has spread to open fields and is considered invasive. Sanseverias are a succulent from Africa, a/k/a mothers-in-law tongue. My property near the St Lucie River is covered with sanseveria under live oaks and sabal palmettos. I've dug them up and cut them to pieces, but runners underground continue to spread them to new open areas. Pulling them up leaves the runners underground. Will concentrated Round Up kill the plant and the runners? I bought Round Up Plus but haven't applied it yet.