Not so great...fungus among us!

This is not really want you want to see INSIDE your living space...

Sort of looks like the Starship Enterprise, doesn't it...and it colonized the inside of my shed with millions of little white spores...

See, I'm not making this up.

SO.  What to DO??  I need to make sure the door jamb is good and dry (good luck with THAT, it catches every splash from the roof when it rains) or kill off the spores, but I don't like poisons.

Any suggestions?