Unlikely. To warm the ground in winter, even when the temperature is well below freezing, you need a lot of firewood, and dry firewood at that. The trees that were cut down were damp, so getting them to light is quite a challenge. If it were that easy, hikers wouldn't bother with spruce branches, stoves, and the like. There's a similar method, but it's used in the fall, before the ground freezes. It involves digging a hole the size of the bottom of the tent, about the depth of a small infantry shovel. A fire is built across the entire area, then covered with earth, and the tent is pitched. Someone who used this method said it was possible to live in the tent in their underwear for a couple of days. In winter, in the Urals, you'll need a lot of firewood to warm the ground and retain heat for several hours. It's more cost-effective to build a shelter and a so-called "long" fire. In the US, it's known as a trapper's fire. By the way, here's a video where a person demonstrates that trying to warm the ground in winter is useless.