I've seen this before, but never to this extreme. I started this cutting the same way I start all of my cuttings. Very simple approach: Heat mat, humidity dome/container, and clear plastic cups with drain holes, filled with damp coco coir and a cutting or two. After I took it out of the humidity container and put it in a sunny window, the exposed roots dried up,  and its back to looking like a normal cutting now. Its an Unknown Italian from Rafaelissimmo and appears to be very very hardy. Thanks Raf!

Don't sleep near it.

Basically, if you have humidity, you can grow roots. The humidity dome makes the humidity more or less even over the full length of the cutting, so all part of the cutting have a good chance to grow roots. But as was said, not all cuttings are equal and not all will respond in this manner. The roots died back when the humidity dropped and they were put in the sun. That is a normal response akin to air pruning or roots that grow out of potting soil.

a yr or two ago, we had very hot rainy days. the trees on my back deck started putting roots out in the branches. i thought something was going really wrong. 

Do I understand correctly that you did not use rooting hormone?  Either way, those roots are amazing.

Hey Scot very glad to see the cuttings doing well, I am going to start your cuttings and some others in the next week so I am hoping for good results, very merry christmas and happy new years to you!

I would  cover those roots with soil.

Scot,
When the humidity is kept between 85% and 90% with temperatures above 70 deg F. fig roots grow. Attached are pictures of cuttings that grew under those conditions in seedling trays.
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