Thanks for the responses. Given how much talk there is on tropical forums about the benefits of (or methods to eliminate) MTS it's been surprisingly hard to find any information about North American native alternatives.
Detritus worms work well for me and become food at times
Interesting. I wasn't one of those who bought into the misinformation that they're a kind of Planaria (those flatworms are pretty distinctive and hard to take for something else), but other than that I didn't really know much about them. Are there any tricks to culturing or acquiring these, or do they just kind of show up without much conscious effort (eggs on plants, sneak into live food shipments, etc.)?
What about some other non-snail critters?
Its a matter of luck, native, substrate burrowing snails can be harder to find then say, the common pond snail, but these sand-stirring snails DO have a similar shell shape to Malaysian Trumpet Snails (At least with the one species I have seen... i don't know exactly what species they were)
I can see where collecting burrowing snails would be tricky. Would it be best to get a shovel full of muck and wash it over a screen? Or maybe look for some eggs deposited on a plant or rock?
Some of the common native snails in eastern USA that look similar to Melanoides are Pleurocera, Elimia (= Goniobasis), or Leptoxis. Check out http://www.fwgna.org/. Not sure how well these do long-term in aquaria.
It would be an interesting exercise. I imagine that, even moreso than with fish, getting the water chemistry of the tank to match the collection site is probably crucial to success.