I gotta admit....I didn't think of that for these weeds and it would be perfect because it's pure pea gravel, no flowers or shrubs....just weeds.
I've got 3 of the 5 gal. propane tanks that I keep full for my propane portable generator so no problem with getting a torch on the end of a hose with a wand. I've seen those things all my life and I must have forgotten about them. I used to see the contractors in the roadway heating the asphalt with one for a few seconds before applying the reflective lane delineators that were pre-coated with epoxy; the heat would accelerate the curing of the epoxy and strengthen the bond.
Thanks, man!