These are fresh bundles of straw which you can see on the left hand side of the top photo. I'm saying straw because I can't imagine it being reeds...
The 'eyebrows' at the top of the roof are lengths of uncut straw which, again, you can see in the top photo. The other end of the run of roofline has been trimmed neatly.
He's still sweeping the roof clear of the cut ends of the bundles.
The lorry is full of the old thatch which must have been pulled down earlier today and thrown into the back ready to be taken away. I wish it had been easier to talk to him but there was so much traffic noise. I can't remember the name on the green logo on the door, all I can remember is that it said 'Master Thatcher', or perhaps it was Thatchers?