Thanks for the additional replies.

I realize now that my problem has been lack of attention given to the deck. Once I clear out all the gaps thoroughly, it'll be easier to maintain.

In my defense (there's no defense really), it's the small front deck off the kitchen on the north side of the condo and it doesn't get used...out of sight out of mind type thing. Still, it needs better maintenance and I'll get on it.

You could always go the more expensive route. Rip the boards off and as long as the framing is sound put Trex or similar on it and be done with maintenance except for an occasional pressure washing.

I do appreciate synthetic for a deck, but it would have to be painted a particular green per HOA rules and I don't think that last on that material. And it is expensive.

I got a cheapy Irwin drywall saw and it made short work of clearing out those gaps. No damage to board radii. It'll be a routine maintenance job every so often, but it didn't take long. A lot of crap falls from the trees.