Dry weather and wildfires have hampered the use of prescribed burns thus far in 2018. As of mid-March, less than 130,000 acres have burned in the Flint Hills region, with Osage County, Oklahoma accounting for 47% of the burned acres (Figure 1).
Figure 1. Flint Hills acreage burned between Feb. 17 - Mar. 16, 2018. Graphic from Flint Hills Prescribed Fire Update.
The question becomes, should I burn this year? Some may have already decided not to burn unless significant moisture is received soon. Safety and concern about prescribed burns escaping have led some to the conclusion to forego burning this year.
What are the reasons for conducting a prescribed burn? Brush control and increased stocker gains often top the list when you ask that question. Decades of data have indicated that a mid- to late-spring burn enhances stocker gains with an average of an additional 32 pounds per animal grazing burned pastures. Stocker gains from burned pastures have almost always been higher, even in dry years. Brush control is more apt to occur once the woody plants are leafed out. The exception is eastern red cedar is vulnerable to prescribed burning at any time. Other reasons for burning include conservation of the native plant community, improving grazing distribution, enhancing wildlife habitat, and decreasing the severity of wildfires. Maintenance of conservation reserve program (CRP) acres is another use of prescribed burning. Normally, CRP acres are burned between February 1 and April 15 in eastern Kansas and February 1 and April 30 in the west. Summer burns after July 16 are also allowed in Kansas. Be sure to check with your local FSA office regarding burning of CRP in your county.
As landowners plan to burn there are some available websites to assist with conducting a safe burn and minimizing the impacts of smoke on populated areas.
- Use the National Weather Service for forecasts. Go to http://www.weather.gov and click on Kansas. Select a site on the map near the location you plan to burn. Find the hourly weather forecast. Good conditions for conducting a prescribed burn and minimizing the impacts of smoke include:
- 45-70 F temperature
- 40-55% relative humidity
- 5-15 mph winds
- >1800 feet mixing height
- 30-50% cloud cover
- Next, check out the website http://www.ksfire.org and use the smoke dispersion model to determine where the smoke from your fire will go. You can access the smoke model by clicking on the small map icon titled “Click Here to Access Smoke Model”. A color-coded map showing the cumulative effects of burning in the Flint Hills area will appear (Figure 2). Green indicates areas where the impact will be small, yellow is the area of medium impact, and red indicates a large impact of smoke from burning on major cities. To determine the direction the smoke from your fire is likely to move, select “Your Fire Impacts,” county, fuel load, size (acres to burn), and date. The model will present the likely smoke plume from your fire over a 48-hour period. The smoke model only predicts where the smoke is likely to travel. It doesn’t mean environmental conditions are safe to burn.
Figure 2. Screenshot of the Smoke Model. Source: ksfire.org
- Another consideration is to determine if the regional air quality is good or bad. To do that, go to the website: https://www.airnow.gov. “Current AQI” gives the combined effects of ozone and PM (particulate matter) on the air quality index (AQI) (Figure 3). By selecting the “More Maps” tab, current ozone and current PM can be seen.
Figure 3. Screenshot of the Current Air Quality Index (AQI). Source: www.airnow.gov
Prescribed burning is an essential tool for maintaining the integrity of our prairies in Kansas. Plan well, burn safely, and remember that smoke from your fire can have negative impacts downwind.
Walt Fick, Rangeland Management Specialist
whfick@ksu.edu
Tags: