New as in it a type of "ludwigia grandiflora" that grows differently than the one that was currently here and it is highly invasive! And as far as "nuking the hole place" to the eyes of the average person could simply be a floating plant treatment where everything Browns out but only floaters actually die and the rest of the plants will green back up in due time! Take some good to get some rid of the bad kinda deal!! U should be able to find some info on the UF Invassive plants website