>>Like a fool, last April I screened an entire 50 pound bag.<<
Yep! I did the same thing to one bag last year. I don't need to buy stuff that will take years to decompose.
The tobacco seeds are like dust anyway, and when they germinate, the seedlings are tiny, like the head of a pin. After a weeks, when they get some size. I can't see them without assistance (mag glass)
I sure didn't need great big floaties in that soil.
/johnny