Symbiots are all-consuming biological...something... that assimilates the local wildlife, spreads like crazy, and operates by a hive mind. It starts out stupid, but as it assimilates more sentient life forms into its neural network, it becomes more and more intelligent.
Its most terrifying quality is that it is capable of evolving to meet new threats. As the infestation expands, its danger and mutative capabilities expand as well. While a weak hive may only be able to churn out semi-capable mutated creatures in order to maul its enemies, a full fledged hives will infect 1 measly human and mutate it into multi-limbed, mult-headed monstrosities with tentacles capable of beheading a full-grown men in a single swipe. Fire and high explosives are the only effective physical means of killing an infestation.
Magic is capable of breaking apart their neural network and delay it for a while, but fire is the only known EFFECTIVE mean of clearing the infestation.
If you are to use magic, and if you are planning to get rid of it, I would recommend the following:
Hit it hard. Use whatever means that you can think of, but just HIT IT HARD. Overkill it and completely wipe out the stain. Immaculate is a mod with a long long memory. If you let even a single strain of the vines survive, it WILL COME BACK AND BITE YOU IN THE ASS. Treat it like you would a particularly virulent strain of bacteria. You keep applying antibiotics long after the symptoms are gone so that all of them are gone.