Edible and Useful Plants of Texas and the Southwest A Practical Guide
A real gold mine for low or no care local food plants. Lots of the plants that have been mentioned on austinperm appear in the book, as well as a bunch of southwestern natives that people have been looking at in a new light--esp. the yuccas and agaves.
Check it out..
There is a version online at google preview (http://books.google.com/books/utexaspress?id=pnnHgcasN-cC&printsec=front...)