Sometimes a person has to build fence in challenging conditions. When ground is frozen it’s almost impossible to drive posts, and very time-consuming and difficult to dig holes. Some people have put an old tire over the spot that needs to be thawed, burning the tires at night, to have the ground thawed underneath them by morning. But burning tires is illegal in most places, and fumes from the smoke are toxic and nasty-smelling. There’s also no good way to control the fire; if unexpected wind comes along, the fire could be spread to dry grass, buildings, etc.
A much better, quicker and safer way to thaw the ground for digging post holes is to use a metal “oven” to contain the fire over each post hole spot. On our ranch, my husband and son had to rebuild some pens near our calving barn before calving season and needed a way to thaw the foot-plus-deep frost. Chipping through the frozen ground was taking several hours per post hole.
So they created some “ovens” for thawing the ground, using old metal protein supplement tubs. Half barrels would also work. To make the ovens they used a cutting torch to make small vent holes (about one inch by 1/2 inch) along the bottom edge (to draw air to keep the fire going) and cut a hole (four to five inches in diameter) in the centre of top of each “oven” for the smoke to come out.
The place where they were building the fence was grassy so they cleared the grass away from each post spot — a short perimetre around each oven — and built a small fire over each prospective hole. There was plenty of firewood handy, with post and pole end scraps from their corral-building project.
They cleared away any nearby flammable debris in case sparks might be blown by the wind. The ovens safely contained the fires, which were right next to the old fence and fairly close to our calving barn. A small mesh screen was also put over each smoke hole, weighted down with rocks, to keep sparks or embers from coming out.
Our son built fires under several ovens and let them burn while working on other parts of the corral, and the frost was completely gone under the ovens within a few hours. The wood smoke was not offensive for working nearby (much nicer than the fumes from old tires would be!) and it was easy to keep track of the fires.
Where the frost was really deep, he scooped out the embers after the fire burned down, dug down farther through the thawed, put the ember/coals back in, and added more wood to continue thawing the ground underneath.
Several days after finishing work for the day, fires were also started in the evening, and we checked on them before bedtime. The fire would eventually go out after the wood was burned up, with just a few coals keeping the ground warm awhile longer, and the ground would be thawed for morning digging.
This innovation greatly sped up the corral rebuilding project, and saved a lot of labour and sore muscles! This is the best way we’ve found for making a winter fencing project easier.