Wow, I feel your pain ... we used to go to the farms and get animal's "fertilizer" and mix that into the soil, all turned up, then anchor newspaper over it to block the sun ... until all the mystery seeds died ... then when the soil was ripe, plant away - good results took a couple of weeks before we were sure the bed was clean.

sounds like me... i have 'fed' my dirt w/ compost, laying down newspaper and cardboard to add nitrogen (the insane amount of worms freaked my dad out, who's a fisherman) and keep weeds at bay, then i had to start buying lowe's cheap mulch. it's such good dirt, the thistle is having a field day. but the plan is to bulldoze the front. hopefully it wont take over the 125-yr+ rhododendron bushes i have. it has made me so angry, i feel like there s/b a clazz action lawsuit against that store.