git-svn: Branching clarifications

I have a few questions about how/when to use git branches when using git-svn (I'm a tad confused...)

Say I've initialised and fetched a git repo involving trunk and one branch (say branch1) from an svn repository.

If I do git branch -a, I see similar to the following:

* master
  branch1
  trunk

(branch1 and trunk are in red for me, which I figure means they're remotely tracked or something like that?)

OK, so that's telling me that I currently have master checked out into my working copy. My question is: where did master come from? Is it a local branch of trunk?

Moving on, say I want to work on branch1. Can I simply issue git checkout branch1? If I do so I get this:

$ git branch -a
* (no branch)
  master
  branch1
  trunk

Which is a bit scary. It seems my working copy is orphaned...

OK, so let's assume I'm supposed to create a local branch of each remote branch I want to work on. So:

$ git branch local/branch1 branch1 $ git checkout local/branch1

$ git-branch -a
* local/branch1
  master
  branch1
  trunk

Am I supposed to have used --track when creating this branch? What are the implications for specifying or not specifying that flag when using git-svn?

So I do some editing on this branch, commit and dcommit. The changes appear as expected in the repo.

At this point if I checkout master, the contents look like local/branch1, which isn't what I'd suspected (that it would be a branch of trunk). What does master represent?

So I checkout local/trunk, and create a new file, commit and dcommit. Umm, it's been committed to branch1 on the repo: not trunk,

So I figure I'm quite obviously doing something wrong here. Could someone give me a hand and tell me what it is I'm getting wrong?

Thanks!