That's what I got my shotguns, rifles, bow, fishing poles, and hunting knifes for.
First thing is to keep what you have safe. As someone else said wait it out for a few weeks while the 'cityfolk' die off then go out for supplies. Until then anyone even remotely shifty looking coming close to the house will get a nice 7.62mm suprise. The Brazos river is four miles down the road. Id load up the canoe with my stuff and start rowing. The woods around the river are packed with hog, deer, coons, and theres always the yummy catfish in the river.
Real problem wouldn't be surviving the wild it would be surviving the people would cant fend for themselves.