use straw if deer are a problem.
I use Timothy hay. It's smaller diameter than Straw and lighter.
My question is, on the frozen ground does s person worry about bedding a trap, so it doesn't move or just place it in the straw and cover.
Place trap on top of ground. Hay under trap to prevent freeze up. Carry some sticks with you to use to prevent trap wobble (if needed).
*Word of caution- Cover trap lightly. Most folks place too much hay over trap. There is a learning curve with hay sets.