I have many colubrids.
...........and I have been using Provent A Mite for many years. Haven't seen one die yet........
Can you list the names of these potentially suceptible colubrid species? How many have you personally seen kick the bucket?
As for the Sevin Dust, I had no idea it was natural and I also had no idea you could put it on your snakes.
I learn something new every day!