Driveway grass control

Here in CA there are regulations, and strong recommendations, about "defensible space" on a homestead or farm to discourage and mollify the impact of our frequent wildfires and to enable either the landowner or the fire department to control fire on a site. One of these is that driveways should be kept clear of vegetation. We have a gravelled driveway some 400 feet long from the road gate to a turnaround near the house, and every winter rainy season progressively more grass and weeds are growing along it, then in the center of the wheel tracks, and finally pretty much wherever. We've diligently hand-pulled a certain prickly offender (puncture-vine) to eradication, but to pursue this with all of it would be impossible. We live simply and do not commute, so we don't use the driveway enough for wheels to crush the weeds. I wonder if this guideline originates from the post-Roundup era and is one of the reasons why gallons and gallons of that stuff are on sale at all the big-box stores around. There just doesn't seem to be an answer without enormous work (like digging all the gravel to the side and putting down barrier fabric, old carpets, plastic, etc. and then replacing the gravel) or a lot of money (such as having the driveway paved) Anyone have an idea?

propane hand held torch that attaches to a bbq tanks and a dolly to put the tank on.
seen here
harborfreight has them for $20.
Walk the driveway after a rain, or when there is dew and singe all of the plants to the ground.
I had a friend who made a potential boom squish attachment out of a small, hand pump sprayer something like this and copper pipe wound around the flame portion, it had pressure release valves, so no boom squish. it shot steam out so fire hazard was low.
it made good steam without having to pull the trigger on the porpane torch. that is, just the pilot light on the torch was enough to get good steam.
It's been a while, but I think we attached the wands together with zip ties and used the trigger on the sprayer for steam production.
not sure if that makes sense, it would require some tinkering, and careful planning to avoid death.
However, we used it and it worked great.

Perhaps, an inexpensive and easy method lies within the underlying soil's pH.

If you could either 'sweeten' or 'sour' the soil out of the weed's comfort range, you could discourage rampant growth.

For example, either lots of lime, or wood ash could make the underlying soil too 'sweet' for strong growth.
Or, Portland cement diluted to a watery, pourable solution would soak into the soil, both sweetening it, and creating a hard crust surface which would further inhibit weed growth.

Alder Burns : This is not a solution to your problem, just a good way to hold everything 'in check' until you can do better ! Get a set of metal bed springs and drag them
down to the end of your road,unhook go to town or whatever, come back,hook up and drag it back to the house - every time you make a trip away, you may have to add
weight depending on how 'hard' the drive way is! Long before you wear out a drag rope you will see a differance Good Luck ! PYRO AL !

Alder Burns : You may want to check out Paul W.s thread on maintaining his farm roads ! Big Al !

My initial thought was perhaps lining the road edges with wood that tends to inhibit growth. So cedar, walnut or locust. This is of course assuming you had access to a quantity of fallen timber that could be set aside for this purpose.

For changing the ph of the driveway, I would be concerned about the runoff into the rest of the yard. I wouldn't want to risk creating another problem for the sake of weed removal.

What is their definition of "clear"? Do they want a permanent firebreak or just enough to slow it down (like a mowed lawn)? We run the mower down it a couple times a year, low as we can without throwing rocks. Fire will still crawl across it, but slow enough to control.

Using roundup will just create a dry tinder bed that is worse than grown plants.

I think I'm going to try the ashes. Being in an area of neutral to alkaline soils I don't really need them in the garden, except as insect dust, and to add to cat litter and humanure litter as a deodorant....so they are sort of accumulating. With so little rainfall I don't really see the alkalinity leaching very far. The idea behind the recommendations is total clearance, I think, so that vehicle tires (as on fire trucks) won't catch fire....