Help! Weeds in my topsoil before laying turf

Hi, can someone advise me on what to do regarding laying turf on weeds. 2 weeks ago i had 2 tonnes of top soil delivered and spent time leveling etc. However I now have millions of little weeds popping up everywhere. Should I spray them with weed killer and if so which one and how long after can i lay my turf. The garden was stones and concrete before so once I'd removed that i rotavated and then spread the top soil. Thanks in advance!

 

I would rake out the weeds if they are only little.

 

Hi thanks. They are small enough to rake but there are hundrds. Won't they just re-root themselves?