Preburning a Blackline with a Propane Weed Burner

So often, when you are planning a burn in prairie, wetland, or savanna, and the weather forecast looks favorable, you find yourself wishing that the parcel already had a firebreak, instead of you having to do a bunch of little tediously managed burns to create a blackline. Because by the time the blackline is finished, the day has warmed up, causing the wind to pick up, and now it’s getting almost too dry and windy to be safe.

Here is Plan B. Go out the evening before, when the wind has calmed, and the dew is just beginning to settle, creating conditions where keeping a fire going is getting difficult. But bring along a propane weed burner and focus on igniting those edge patches of fuel that will still burn with a bit of encouragement, those clumps of big bluestem, or patches of cattail, or little windrows of oak leaves.

Because these individual little fire patches cannot spread, you can move along briskly igniting them, if your equipment lets you. You can quickly preburn 60-70% of the easily ignited fuel in this patchy blackline, and it will be nearly as effective tomorrow morning as a clean burn, because most of the easily ignitable materials will be gone. So when you and your crew show up midmorning, as the last of the dew dries, you are ready to do the main burn, and get finished before the wind really kicks up.

The awkward part of efficiently handling the weed burner is that you ordinarily need one hand to aim the flame tube, one to manipulate the propane flow valve (flame size), and one or two hands to carry the heavy propane tank – depending on how full it is. Today’s post is to mention that this can become more simple and ergonomic by modifying a pack frame to carry the tank, and free up your hands to just manage the torch. An ordinary stout plastic milk crate’s inside dimensions are 1’ x 1’ x 1’, and a BBQ-sized propane tank outside diameter is often 1’, for a perfect fit inside the milk crate.

So all you need to do is firmly attach a sturdy milk crate to a comfortable pack frame, put the BBQ tank in the crate, and you are ready to roll (see photo). My weed burner will throw a four-foot flame if opened up and this really encourages slightly damp vegetation to burn. In daylight, an aggressive propane flame is nearly invisible, but in the gloaming, every detail is clear, so it is easy to keep adjusting the flame to match your fuel and preburn your blackline. In the photo, the flame is turned way down to smolder, in order to be yellow and visible.

When working alone, I find it convenient to set the assembled rig on the tailgate of my pickup, and it becomes easier to maneuver myself into the shoulder straps (compared to putting it on while it is on the ground). Having a stool to sit on makes it even easier to get the pack in place, but if you are less than 77 years old, this probably isn’t necessary.

So this spring, try out some evening preburning of blacklines in a very safe location, and if you like it, move up to backpacking a tank and weed burner torch.