Repair old deck

[RobertJ25]

This is not really my first post,  as I used to be fairly active before the software change.  My old account was tied to an old email address which I can no longer access.  The easiest recovery for me was to open a new account with my newer email. 
The question:  I need to repair a section of a deck that is 25 to 30 years old. It was build with pressure treated 2 x 6 deck boards which I have carefully maintained and which show no signs of deteriorating.  The problem is that I built the deck to surround a tree.  Nice idea at the time but now the tree  is 65 years old or so,  and is an ash,  and has died,  and I am having it removed.  I am preparing to remove the boards adjacent to where the tree is,  and repair the hole in the deck.  My problem is,  it was build before the days of deck screws.  We used galvanized spiral nails.  They did a really good job,  and I am anticipating a lot of grief removing them.  Repairing the deck will not be a problem as I built it in 8 ft by 8 ft sections,  in a checkerboard pattern,  and the tree is contained within one of the sections. 
I suppose that I could put a metal cutting blade in a sawsall and cut them off,  but I would welcome any other suggestions for removing these nails.
Bob

[mad_planter]

sawzall would do the least amount of damage to the wood if you want to reuse it.

[Cooler]

Use your circular saw to cut close to the nails and then break out the  remaining wood with a hammer.

Once the nails are exposed like that you can try prying them out but I think is will be easier to cut them off.

Use a right angle grinder and cut off the nails.  They will cut in a flash.  Wear long sleeves and long pants and goggles. 

Of course it is possible that your new screws will hit the old nails but I can't imagine that there will be very many of those situations.

[AUswimKC]

drill a hole in the deck boards close to a joist big enough for a sawzall blade. use a flush trim bit in a router to flush the deck boards with the joist. screw on a 2x4 to the top of the joist to support the new boards.

Just stagger your cut ends. no need to mess with the spiral nails this way

[RobertJ25]

Thanks guys !  I found an item called a "Duck Billed deck wrecker".  It looks like it will do the job with minimum punishment to the arthritis in my right hand.  If I end up with many orphaned spiral nails stuck in the joists,  I will go buy a low end angle grinder and cutoff blade.
Thanks again for the input. 
Bob

[rwe2156]

You may be surprised how easily those nails come out after 25 years.

[Guest]

I redecked a dock, and the best tool was a tamper head digging bar. Tamper at one end and chisel shape at other end.
Little effort to pry boards up. Lots of leverage!