A Couple Permaculture Questions

Hi there. I signed up for a Permaculture class last fall but had to drop it due to an injury. All I've been able to do since is a little reading and I learn techniques better from people than books. Here are some questions that have come up for me. I hope folks here will chime in if they have an answer...

1) Permaculture likes the natural build-up of mulch. However, if you've got a tree with fireblight or peach leaf curl, the usual recommendation is to get rid of all diseased material from beneath the tree and dispose of it in the trash. What is the permaculture approach?

2) I have a lot of trouble with field bindweed in my yard. I understand that this is a pioneer plant and that eventually through succession pioneer plants are supplanted by perennials. However, field bindweed seems like a special case. It strangles the perennial plants that you'd hope would shade it out. It's a HUGELY successful competitor. What is a permaculture approach to field bindweed? I'm assuming you don't just leave it alone. My injuries and surgeries this year meant that I left the garden alone a lot more than I would have and the fiend bindweed actually went to seed so now it's competing via incredibly long strong roots, seeds, AND strangling other plants.

3) Speaking of pioneer plants, as long as I'm going to be encouraging pioneer plants to do the soil building, I'd like to use SF Bay Area native plants as much as possible. (I'm not a native plant hardliner, but I figure that I'd like to provide some habitat for natives.). Does anyone have a list of such plants? I'm going to try to get by Native Here Nursery so that I can get Vicia gigantea there (the only place on this side of the bay I can find it), but are there other nitrogen-fixers, tap rooted, etc. native plants that would be useful in trying to accelerate succession?