Amberjem -
The best thing I've found to deal with blackberries is goats. Just set a fence around them and they'll chew them down to the ground. I had pygmy goats that took out HUGE 7-foot high berms of them. Much better than having to go to County Ag and get registered for special specific herbicides, etc...which didn't work well at all.
Sam, yeah, I was even all non-condescending and stuff... So, been to the mailbox yet? Today is the last day of the window they gave for how long it should take.
I may have to venture out and check but even the 200 or so meters of highway to the mailbox are deadly right now... Not joking whether I took my truck or walked I don't think I can risk it for chocolate....