A worn and leaky pair of boots once cost me a chance at a mature bull elk. I was hunting deep in the remote wilderness of Utah's High Uinta mountains. It was cold—so cold that my Nalgene water bottle froze solid through at night, even when tucked next to me inside my tent.
As I crossed a snow-covered marsh, my boots broke through the frozen crust several times. I hadn't counted on warmth from the underground water softening the ice. By the time I made it to the meadow I was looking for, my feet were wet inside my wool socks, and I knew I was in trouble. No matter how I tried to keep them warm, my feet grew colder—until eventually I had to leave my post or suffer serious frostbite. When I later returned in dry boots, there were seven sets of fresh elk tracks crossing the meadow, one of them a mature bull. Had my feet been dry and warm I likely would have made meat that day.
Most good boots are waterproof, with Gore-Tex or similar lining. It's great, and for the whitetail hunter who walks a couple hundred yards to his stand the waterproof membrane lining will last for many seasons. But the western hunter who hikes many miles a day on foot will eventually break down Gore-Tex and similar products. The battering and constant flexing caused by hunting in steep, rocky terrain will stress the membrane and will compromise it's ability to stop water from entering. My boots typically begin to leak after 40 to 50 miles of rough mountain hunting. Another common mistake that hunters make is warming their feet by the campfire. Heat melts Gore-Tex and will render your boots leaky immediately.
Since that cold day high in the Uinta's I've learned that with a good pair of all-leather hunting boots my feet can always be dry. Here's how: At the local hardware store pick up a standard wax toilet ring. Approximate cost: $3. I've tried mink oil, lexol, neatsfoot oil, and many other boot sealant products, including the spray-on variety, and none work as well.
To apply, simply wipe the boots clean and set them and the wax in a warm place, near a heating vent, in the sunshine, or near a woodburning stove. Don't get them hot, just nice and warm to the touch. Then, using your fingers or a small cloth, rub the wax into the leather. If you don't want to waterproof your fingers, wear gloves. Avoid getting wax on the plastic/rubber parts of the boot. When the boots are nicely coated with wax, set them back in the warm spot for an hour or more - once again don't allow them to get hot. Then using a soft cloth, buff the excess wax away.
When you are done your boots will appear much younger, the leather will be more supple, and will be more waterproof than a duck. The effect will last for weeks of hard use, and when the boots start to look scuffed and thirsty just repeat the process. I use the wax on my hunting boots, work boots, and even my cowboy boots.