I live in florida and happen to find this thorny plants with roots that look like the ginger root (usually around the fence line). Can anyone help me identify this?

Any chance of adding pics to show what the leaves look like?

Also if there are remains of stem, vines, any remains of thorns or dried leaves, maybe dried fruits, all those information will be very usefull, since this is autumn in north part of the globe.
Mean while I suspect a Smilax tuber ready to dormant, the Greenbrier vine. it is a long shot though.

Smilax. Catbrier (Smilax)

Yes, those are the rhizomes/roots of some type of Smilax but it's impossible to identify which one without seeing the leaves; there are numerous species of Smilax native to Florida.

Take a look at some of the photos in our database for these species that are found in Florida:

Earleaf Greenbrier (Smilax auriculata)
Saw Greenbrier (Smilax bona-nox)
Cat Greenbrier (Smilax glauca)
Bamboo Vine (Smilax laurifolia)
Lanceleaf Greenbrier (Smilax maritima)
Walter's Smilax (Smilax walteri)