I'm new. I had a thought.. What about building a hoophouse over small fig trees to protect them from the elements. Is that ever enough??  I'm in NY

You should check this out.

http://www.greenfingardens.com/2015/07/semi-pit-tunnel-greenhouse-update-lots.html?m=1

The guy has a 2 foot deep trench hoop house and kept bananas in it that thrived and fruited. The link is just one post about it, you can find others, including the one about building it, in his past blog posts.

Sounds very promising, I'm thinking about doing one myself.

I have thought about doing something like that as a season extender. I am in Zone 5a so if I could get my trees started in late march or early april instead of early May I should get a larger harvest especially on the trees that need a longer season. A hoophouse for me wouldnt provide adequate winter pretection.

the video is about a low tunnel and has figs growing inside of it. He seems to have success with it. Channel is badassfarmer video is How to grow figs.

I JUST finished watching the video. 
Thanks guys;)
I'm 6a, and it seems like these would extend the season- which may be very important at the end for harvesting. But I'd still need to wrap in the winter.

See this thread from 5/18/2015. You can get a big jump on your growing season, and extend it by a month, maybe more.

http://figs4funforum.websitetoolbox.com/post/greenhouse-update-leafed-out-and-growing-strong-7409265?pid=1287207490

This is the beginnings of my 7x7x15 greenhouse.  Its just 16'x5' cattle panels.  Was very easy to setup. Might be a tad low for trees but you could go narrower and get more height out of it.  $20 a panel I believe it was.  Im going to heat it with a radiant heat oil heater in the evenings and some solar heating methods.  For the cost, im happy with how its turning out.  Im in NC so the winters arent that bad but I think the cattle panel would hold up to snow.
 

You can build a smaller 1 or 2 panel setup on top of your trees, you dont need a tarp as a base, I just put one there for my application.

Enjoyed thevideo and picture of the cattle panel hoophouse

Love that hoop house with bananas.  I'm in AZ, so I don't need it for figs (I don't think, anyway) ...but for my bananas that's awesome!  Hello, hubby...new project!!  (haha)