Ok, I plan to cover the dirt in my crawlspace with plastic, as a
temporary measure to reduce humidity down there. Yes, I realize that
this is not a permanent fix, and yes, I realize that I need to address
the source of the moisture problem.

Here is my question: Do I need to treat the dirt with a chemical spray
first, before laying plastic? If so, what chemical? I am thinking
that if mold/mildew is a potential problem, that something nasty could
happen to the dirt if it is cozy in plastic for the winter. Opinions
please...

Todd