Prescribed burns

Jan 09, 2022

Our property is the sum of several contiguous stretches of land. Each lot had a different owner and we ended up gathering woods, pastures and row crop fields. Fields and pastures were turned into prairies by planting native species. These prairies require regular maintenance to rejuvenate the plants and to control trees growth.

Prescribed burns, also known as prescribed fires or controlled fires, refer to the controlled application of fire under specified weather conditions for ecological, silvicultural and wildlife management purposes. The list of benefits below is not exhaustive:

  • Reduces hazardous fuels, protecting from extreme fires;
  • Removes unwanted species that threaten species native to an ecosystem;
  • Provides forage for wildlife;
  • Improves habitat for threatened and endangered species;
  • Recycles nutrients back to the soil;
  • Promotes the growth of wildflowers.

 

The minimum requirement for liability protection comprises the following:

  • Must have at least 1 certified Prescribed Burn manager on site supervising the burn
  • Must have a notarized burn plan at least 1 day prior to burn
  • Must have a permit from the Mississippi Forestry commission for the day of the burn
  • Must be in the public interest and not constitute a nuisance.

A plan that states How, What, Where, When and Why burning is written by the burn manager who defines the protocol ahead of time, specifies the area to burn (it is critical to take time to scout the area a few days prior burning) and include the techniques to be used.

The plan once notarized becomes a legally binding document.

In order to get a Burn Permit, the burn manager has to call he Mississippi Forestry Commission Dispatch, which will either be issuing permits or not for that day. The permit is mainly for smoke management. If a permit is issued the dispatch will ask for more information:

  • location
  • county
  • section
  • township
  • range
  • Landowner name and who is responsible for the burn
  • how many acres to burn

A permit may be issued for that day and the time permit (how long it is valid for) is in effect.

The reason for burning has to be explicit in the burn plan.  A prescribed burn must be conducted in the public interest:

  • Reduce wildfire hazard
  • improve wildlife habitat
  • site preparation
  • weed control
  • improve access

It certainly does not mean – it’s a beautiful day, think I’ll go and burn the ‘back 40’ just because….

Smoke is the greatest liability when burning and this is why a permit is necessary. Specific conditions have to be present to ensure an adequate dispersal of the smoke.

The minimum burning permit criteria are:

  • mixing height of at least 500 meters and a transport wind speed of 3.5 m/s
  • or, mixing height of 890 meters and a transport wind speed of 3.0 m/s

There are several rules of thumb to consider:

  • being aware of the latest weather and smoke management forecast
  • the relative humidity will halve with each 20 Fahrenheit increase in temperature in a given air mass
  • not burning when the relative humidity is below 25 percent
  • burning when mixing height is above 500 meters
  • not burning in temperature inversion
  • never burning during a drought
  • heading fires produce 3 times more particles than backing fires
  • the logging debris have to be started burning by mid-morning
  • 1 ton of fuel per acre is being consumed by smoldering combustion during poor nighttime dispersion conditions limiting visibility to 1/2 mile maximum within 1-1/2 miles of the fire.

If we put smoke in the air, wherever it goes, it is our responsibility.

Caution is required when nearby up-wind or up-drainage smoke is possible in sensitive areas. The smoke sensitive areas and smoke critical targets are the roadways, the numbered highways, the hospitals, schools, elderly, chicken farms.

Furthermore each burn needs to be preceded by a safety briefing.

I personally do not like burning at night, it is difficult to keep control of all the fire lanes. In the case below the fire went over the railroad tracks. We could contain it, hopefully. I went with Maggie the following morning to check the consequences.

Perennial plants will then quickly emerge from under the ash.

Prescribed Burns are important tools for prairie management but they require the greatest preparation and care.