After a long day of weeding, you have a wheelbarrow full of “useless” plant matter (if you haven’t been keeping up with the mulching, that is). Should you compost the weeds? From the University of Oregon, here’s a list of what you can get from harvesting your weeds and composting them: Dynamic Accummulator Weeds. Includes a printable version. There’s another connection at the permaculture wiki: http://permaculture.wikia.com/wiki/Dynamic_accumulators that breaks a lot of them down into descriptions instead of a chart. Wikipedia has a similar link with additional information up front http://en.wikipedia.org/wiki/Dynamic_accumulator. There’s a good light article at http://hubpages.com/hub/Dynamic-Accumulators-for-Better-Soil that goes into some more detail as well, suggesting you can use some of these as cover crops or companion plants. For the book hungry, there’s a book listed in the usenet newsgroups: Designing And Maintaining Your Edible Landscape Naturally that amazon currently sells, though you may be able to get it at the local library as well. Mentioned are the more obscure sulfur accumulators:
"...Calamus, Caragreen, Coltsfoot, Eyebright, Fennel, Garlic, Meadowsweet, Mullien, Mustards, Nettle, Plantain, Rest harrow, Watercress, waywort. "The Fennel , mullien and many mustards have nice taproots. Nettle, Meadowsweet, coltsfoot, plantain are all good on moist sites. ..."
Bottom line: I compost the weeds.