Do fox hunt open fields when the ground is frozen and/or snow covered, or do they stick to hunting prey in thick cover in these conditions?

Yes, they hunt mice and voles in open fields or heavy cover on a regular basis.

Our ground is frozen, hard as cement, and snow covered past few weeks.
During this time, Canines spend more time near thickets and under Pine thickets with less snow. Also, the sunny side of ridges & mountains.
Open fields, Canines throw us a change up during freeze up. Now, they also travel frozen creeks, ponds, swamps, lakes & rivers, even the smallest frozen water.
Canines do travel fields & travel for breeding season or check out a Groundhog hole in open fields. During these extreme conditions, I see the most tracks, concentrated tracks in or near cover.

When things freeze up it just broadens their hunting areas.

Had a pair hunt part of a 40 acre field last night. Completely frozen and 6" of snow on it. The farmer worked it up and installed tile beginning of December, they worked every clump of dirt/grass they walked by. On the other side of the road they are sticking more to heavy cover.

Yes

X2

Any and every knoll or high spot in a field they will check out. Clumps of grass that push up, dirt clods, rocks

Seems like they’d nearly starve to death in many parts of their range if they didn’t...

Around here if there is decent alfalfa stubble and we get snowfall that area becomes a real haven for mice and thus predators as well. Soybean stubble on the surface not tilled in with snow cover is very good as well.

Bryce