How odd, I was just planning on planting a fig tree here on MV which has the same climate as most of LI. My co-worker is from LI and he remembers a neighbor who had fabulous fig trees that were covered in burlap and tar-paper during the cold weather. This was on the south shore right on the canals which might be milder than where you and I are. But then again it was 50 years ago when winters were colder as in your grandfather's day.

Let me know what you learn and vicy-versy......

I don't grow these myself, but my friend grows them and she buries them for the winter. I helped her one year dig a trench, and she had several small (two to four foot trees) and we laid them in the trench, covered with soil, and then covered with hay bales.

I honestly don't know what she does with bigger/older trees, although I believe hers are all potted. Perhaps she brings them in the garage? I did a quick internet search but everything about overwintering seems to deal with potted figs. Maybe you could do a more thorough search.

Good luck!
:)
Dee

Here is a link that might be useful: figs in winter

There were articles in the past in both Fine Gardening and GardenGate magazines, but I can't find them online. Whay I do recall is the Brown Turky cultivar was the most hardy of the figs but even someone growing them in Pennsylvania needed to really protect them in winter.
The link below is an answer someone from the New York Horticultural Society gave to a person living in Brooklyn.

Here is a link that might be useful: Growing Figs in New York