Fire Behavior in Untreated vs Treated Areas

Fire Behavior in Untreated vs Treated Areas explained by Mark Brown, the Executive Officer of Marin Wildfire Prevention Authority.
#MarinCounty #WildfirePrevention #FireSafeMarin

[@B30pt87]

Beautifully done! Thank you guys for making these videos.

[@theofitanides2212]

Thank you so much for making this video. I havent yet seen an organizational scale fuel treatment like the one you draw in the video. Is the drawn spacing to scale? If so, where can I tour a site or get pictures? This looks very different than a CAL FIRE type shaded fuel break, and that piques my interest.

[@FIRESafeMARIN]

@theofitanides2212 this is just an illustration of fire behaviror in treated vs untreated areas and not drawn to scale.

[@mushroom_thrillers]

Excellent graphics and clear information. Thank you! But what happens to all the “slash”? The material that is cut out could add up to tons of branches and detritus - even chipped, does it become its own fire hazard?

[@marinwildfirepreventionaut28]

Excellent question. If the removed material isn't disposed of properly, it can create its own problem. Some of the materials are chipped on site, but we limit the depth of the distribution of the chipped material in a way that it does not exacerbate the fire problem or inhibit native plant growth. Some of the material is removed from the site and taken to mulching facilities. And some of the material is piled and burned on site. This is the case in remote areas where removal by hand is not an option.

[@Tom-wh9ip]

Overall I really like the explanation and format of presentation. The part that confuses me is the part about maintaining the continuity of the canopy. I'm not sure what distance scale you are using from the homes in your schematic. The NFPA recommends having an 18' gap between individual tree canopies or small groups of trees when within 30' of the home, 12' gap between tree canopies when 30-60' from the home and 6' between tree canopies when 60-100' from the home. These distances increase as slope becomes steeper. The idea, I believe, is to help bring a crown fire to ground level. Your reasoning is that a maintained continuous canopy will have better moisture content due to less drying of the soil and the surface fuels will be moister. This makes sense too. How do you resolve these contrasting recommendations. Will the moister continuous canopy stop a crown fire. Do the NFPA distances really bring a crown fire to the ground? Is there a scientific study to back up either approach. Thanks in advance. Tom

[@marinwildfirepreventionaut28]

Excellent question and we are so glad you are digging deeply into this topic. Unfortunately, there isn't a one size fits all solution. Yes, near homes, canopy separation of certain species of trees is desirable. Slope obviously plays a big part. In our eyes, it is more important to treat the ground fuels and ladder fuels than separating canopy. When it comes to tree species, we feel it is more important to create canopy separation in the conifer species whereas deciduous require less canopy separation.