"In the scummier parts of Haiti and Nigeria I worked (so I assume the entire 3rd world), shardes of broken glass are set in clay or wet concrete at a pointy angle. It makes for a primitive concernetta that will shread anyone going over it.

So, given enough broken dishes, cups, windows, and mirrors - you could set up a glass shard FIELD 5-20 feet across that would slice people up if they tried to pass it. "

"Makes me wonder exactly how much of a caltrop field it would take to stop a zombie.

I'm sure a few feet would shread their feet and put them on the ground. A few more feet of crawling would slice them into flopping fish-slugs. A ditch on the inside would trap the slithering ones until you could come by and dispatch them."

"Of course, if I was repurposing a subdivision into a farm, I would simple choose a solid house to covert into a barn without the extra construction (a house with a full basement with good drainage would be ideal."