Brush fire: Type of stream

[HF&R_H28]

On a brush fire, during mop-up, do you prefer strait stream, or fog stream. I have always been taught to use straight stream, to get down into the ground, and stir it up, and soak it all. But there is one person who always tells me to use fog stream, to flood it. Since I am a junior, I listen to him. What I want to know is what do you prefer and WHY.

[SilverCity4]

Depends on the type of fuel you are trying to extinguish.

If you’re in the woods with several inches of leaves, I would use a straight stream to get down deep and penetrate.

If you’re in the middle of a pasture with light grass, I would use a fog. The water will soak through the grass and give a little buffer zone on both sides of the fire line.

If you’re mopping up in thick grass, like buffalo grass, a straight stream is probably more appropriate.

Now, when I’m directly attacking a grass or brush fire, I’m constantly adjusting the stream, depending on what I feel is more appropriate to extinguish the fire and conserve water.

I don’t think that this is a very black-or-white issue--there are just too many variable to consider.

[NJFFSA16]

I've had some experience in this type application.;) Beware-long post!

For running surface fires...use whatever you need to knock it down. Fog, to cover a wide area...solid stream for reach. Mop-up is a whole different approach.

Mop-up Ops

It depends on what type soils you are dealing with. Here, in northern NJ...we have hardwood forests, with a heavy duff/humus layer, which can be anywhere from 2-8 inches in depth....before you reach mineral soil. When the surface fuels burn, the duff layers and small roots may be ignited, depending on the moisture content. This is called groundfire. It may be burning 8 inches or more, under the surface fuels.

IF you are doing mop-up that may involve groundfire, you can not use fog to completely extinguish it. The water does not penetrate more than an inch or two below the surface area...and the result is what we call "mudcapping." In effect, you have created a layer of water, duff and soil over the burning roots and humus. The water never makes it to the smoldering root strucutures. Eventually, the smoldering fire follows the roots back to the surface...and if it pops up in fresh fuel, you have rekindle.

The water must be applied so that it penetrates the layers and soaks completely down to mineral soil. Here's the secret. Groundfire is not always visible to the naked eye, as it will smolder underground, quite possibly undetected. A light mist or fog application will result in steam rising from those areas which contain groundfire. Once located...these areas of groundfire must be bored out with a solid stream application that will penetrate the duff layer...down to mineral soil. You can assist that by digging and turning the soil over as you apply water. We use a low gallonage straight bore nozzle to accomplish this...in order to also conserve water. In areas with extensive groundfire...a Class A foam is added to the application...which aids surface penetration. It is a very tedious process...also very time consuming. But it is the only way to effectively extinguish groundfire. We have spent days on small acreage fires...working on groundfire near the fire perimeter. (Usually, 20-30 feet from the line)

If groundfire is not a problem...and you are dealing with fire on the surface only...it can be effectively extinguished with fog. This would be a common application in areas with sandy soils and little duff or root structure...OR when moisture content of the fuel is sufficient to prevent it from burning below the immediate surface.

It's something you really need to show firefighters...rather than attempt to explain it. During drought conditions here, we need to remind the municipal departments about groundfire...and mudcapping. It's easy to determine who has mudcapped groundfire...you hear them on the scanner...getting called back to the same location repeatedly.
It's something you need to be aware of....if you have the type soil that is conducive to supporting groundfire.

We've had fires here of under an acre...where the running fire is controlled in a matter of minutes...and then we spend hours, sometimes days...checking for and extinguishing groundfire. If unchecked, the result will probably be additional running fire, as it surfaces somewhere and the wind gives it that little push.:D

HF&R_H28....I hope this helps.

[medford]

I must agree with the last post, do any pattern to knock the suckker down. It's an ongoing evauation to see what exactly works. Class A helps, good thinking to use.

MOP UP
the only mop up done propperly is with a tool and water. a good mop up will take some time especially with that amount of Duff. out west here we don't get that bad of duff but yes with roots. The only way is to get a tool(shovel, combi, pulaski anything other than another hose) and just "hydromine" the area. When you do a good mop up it should look like a garden ready to be planted since you have "rototilled" the earth. It's just like they say with camp fires:"Soak, stir, soak, stir..." till it's cold.

Mudcapping, I've seen it in the extreme. One fire the hand crew I worked on IA'd a fire on another district. We contained it pretty quick and had us bed down for the night to be available for the next day. The IC had a night crew come in and "babysit" the sprinkler's the (IC's little Idea to place impact sprinkers on the sprinkler all night. have the night crew rotate and soak the fire) That was the Dumb mistake or "learning experiment" I've ever seen. Working on a decent slope with mud everywhere and down 6". we did what we could and for the next week or so they had to patrol, and work all the spots where the mud dried enough for the fire to puff smoke to show itself. Having the sprinklers on a hose trailer has it's good points but that's another thread.
Sorry for the run on but good thought it was useful.

Like i said earlier you must soak, stir, repeat. The use of Class A, is good, solid bore to help "seek and destroy" the hot spots are useful but ya just gotta sweat and use the tool to get the task done. More so with heavy woods than open range land with sage and grass. That is a circle and drowned, but pay attention to the areas with large sage, plant growth, check it well.

Here's another tip for you to help find the hot spots:
Look off the ground and you will usually if not always find a small swarm of insects flying right over the "hotspots."
Just remeber to be METHODICAL and USE A TOOL.

[NJFFSA16]

Originally posted by medford
Here's another tip for you to help find the hot spots:
Look off the ground and you will usually if not always find a small swarm of insects flying right over the "hotspots."

Very nice tip! You can work on my crew anytime medford! It's tough finding the firefighters with extensive groundfire experience...and obviously, you've been down that road.:D

[HF&R_H28]

Thanks for the info! i have been using a tight fog patteren lately. That is an excelent tip Medford! now if we could just have some rain. We got lucky on a brush fire this morning... we were in an area, where people ride horses, that is at least 2 miles back in the woods on a washboard dirt road. When we I got there, all fire was out. and we still needed to plow around it. near the field was a tractor with a Disk harrow. so my chief hopped on it and plowed it. How much better can it get?