Evergreen alders (Alnus jorullenis) near fruit trees (etc)?

Hi all,
Are all alders as good as eachother for nitrogen fixing, or other benefits, for planting near fruit trees?
Varieties of trees are very limited where I am (Tasmania, Australia), but I just found I can access Evergreen alders (Alnus jorullenis) for a decent price where I'm taking a trip to tomorrow, so don't have much time to look them up!  I had had the thought previously that I was going to plant Alder in between my widely spaced cherries & plums.  
Is this alder any good for that?  Or failing that, it would still be a good fast growing tree for a windbreak, wouldn't it?