When to pick the hops off the vine?

[Barney Fife]

I have hops growing wild all around me, thanks to a neighbor who planted some on his property some 30 years ago. Now that I've gotten the hang of malting my barley, I may as well make a batch or three of beer, and I want to use these hops. The flowers are now about an inch long, they feel dry and papery like I've read about, but they seem small, still. Is there an accurate indicator of when they're ready to harvest?

And no, I have no idea what type of hop vines they are, as the fella who planted them passed away some years back. Can they be identified somehow?