How does fire impact ticks?

Ticks, chiggers, horn flies, and other external parasites can be reduced with fire. However, studies have shown parasite reductions are generally short-lived with parasites typically returning to pre-burn levels within a couple of seasons.

 

Relevant literature:

Cully, J. 1999. Lone star tick abundance, fire, and bison grazing in tallgrass prairie. Journal of Range Management 52:139–144.

Drew, M., W. Samuel, G. Lukiwski, and J. Willman. 1985. Evaluation of burning for control of winter ticks (Dermancentor albicuptus) in central Alberta. Journal of Wildlife Diseases 21: 313–315.

Swengal, A. 2001. A literature review of insect responses to fire compared to other conservation managements of open habitat. Biodiversity and Conservation 10:1141–1169.

Burning Safely and Effectively

Several things must exist for a person to consistently conduct safe and effective prescribed fires or controlled burns. These include appropriate education, experience, goals or objectives, adequate burn plan, site preparation, proper weather, labor, equipment, ignition sequence, smoke management, and mop-up. When a person conducts a burn, they should appropriately address all of these issues. At first glance, this may seem a little overwhelming, but with some training and experience, most folks can easily develop the skills to burn safely and effectively.

Education

Prescribed burning workshop participants listening to a fire equipment presentation

Each potential fire manager should obtain adequate education by reading publications and participating in courses, seminars, workshops, and or field days addressing fire management. Information should address safety, smoke management, fire prescription preparation, fire behavior, fuel issues, plant responses to fire, animal responses to fire, ignition procedures, laws, sociopolitical issues, and others. Although a few days of thorough, well-organized educational effort and adequate experience might be enough for a person to start burning, fire education should be viewed as a lifelong process because there is much to learn and the science continues to grow.

Experience

Experienced fire boss coaching a new prescribed burner

Each potential fire manager should obtain adequate experience by assisting on burns with skilled fire manager(s) burn before conducting their own burns. Burning is similar to driving a car where we learn much by reading and participating in educational courses, but we do not become safe, skilled drivers until we operate vehicles for a while. We learn how hard to push an accelerator or brake, and how much to turn a steering wheel primarily from experience rather than from reading or courses. Similarly, we learn how to set  fire and how to interpret and react to fire behaviors primarily from experience rather than just academic knowledge. Most people continue to learn from experience even after hundreds of fires.

Goals

Goals and or objectives should be established for each burn. These goals can be specific for livestock, wildlife or forestry objectives or a combination of all. The goals or objectives then guide fire prescription preparation, site preparation, suitable weather conditions, labor and equipment needs, etc. Goals or objectives help us aim at a target so we can consistently hit it or get close to it.

Plan

Much of the work involved with conducting a safe, effective burn occurs in the planning stages. A burn typically should be planned months, sometimes more than a year, in advance to provide adequate time for written prescribed fire plan preparation, fine fuel accumulation through rest, firebreak preparation, coarse and volatile fuels management near firebreaks, labor and equipment arrangements and preparation, and neighbor and civil authority notifications. A written prescribed plan is one of the things that separates a prescribed fire from a well-intentioned, but sometimes poorly planned, controlled burn.

Site preparation

Site preparation involves delineating and preparing firebreaks, moving coarse and volatile fuels away from firebreaks (or alternatively, moving firebreak locations or adjusting firebreak widths to address coarse and volatile fuels), accumulating adequate fine fuels, and sometimes modifying fuels mechanically. Most physical labor and or heavy equipment activity that might be necessary for a burn typically are involved in site preparation. Areas grazed by livestock may require deferment via closed gates or a patch burn grazing approach to accumulate adequate fine fuels.

Weather

The burn prescription developed during planning establishes acceptable wind directions, wind speeds, relative humidity, smoke management guidelines, and air temperatures to accomplish goals or objectives with the available fuels, firebreaks, labor and equipment. A burn manager should closely monitor weather forecasts to determine when weather conditions are suitable for a burn. When weather parameters are outside prescription, a burn is a ‘no go.’ Without a high level of skill and site preparation, most burns should not be conducted when wind changes directions, wind speeds are above 20 mile per hour, or relative humidity is below 20 percent.

Labor

The minimum amount of labor needed for a burn depends upon area size, site preparation, crew skill level, and the written prescription. With adequate skill and site preparation, some burns can be safely and effectively conducted with only two to three people, whereas other burns may require crews of seven or more. However, one person is not an adequate burn crew because no contingency exists when a single person gets sick, gets injured, or must leave the site.

Equipment

Drip torch being used to ignite fire during a prescribed burn

Minimum types of equipment needed for every burn include ignition, fire suppression, communication, and personal apparel. Ignition equipment usually includes matches and one or more drip torches; fire suppression equipment usually includes one or more water sprayers or pumpers, but also frequently includes other equipment such as leaf blowers, rakes, swatters, backpack sprayers, and or shovels; communication equipment usually includes at least one mobile telephone, but frequently includes other mobile telephones and or two-way radios; and personal apparel includes fire-resistant pants, shirts and or jackets, boots, gloves and hats. Other equipment can be helpful or needed, such as drinking water dispensers, fuel containers, chainsaws, fence pliers, water hoses, axes, and weather meters.

Ignition sequence

Each burn should be ignited in a certain sequence to prevent fire escape and minimize smoke problems. Many firebreaks are not wide enough to stop a headfire. Usually, backfire, flank fire, and strip headfire are lit along firebreaks to create blackened areas that effectively widen firebreaks. Most time spent burning is allocated to burning areas along firebreaks to prevent fire escape. Generally, relatively little time is spent igniting the headfire. Headfires are not used in some burns due to escape and smoke considerations.

Smoke management

Smoke management should receive significant consideration in the written prescription. More problems are caused by smoke than from the flames. Smoke can move and cause impacts many miles away from a burn. Smoke should be kept away from highways, airports, schools, nursing homes, towns, and residential areas. Fire crews should always monitor smoke because it can indicate when a fire is burning in an inappropriate location or manner.

Mop-up

Fire crew member mopping up after a prescribed burn

A fire manager and crew should remain with a burn until all fire is safely contained within the perimeter. Burning and smoking items near firebreaks should be completely burned, moved away from firebreaks, or extinguished before the crew leaves. After the crew is allowed to leave, a fire manager should continue to monitor a burned site every day until all smoking debris is extinguished, which may be a week or more in timbered areas or areas with wood/brush piles.

Prescribed Fire Equipment

The minimum equipment needed for every prescribed burn include ignition devices, fire suppression, communication, and personal safety apparel. Other equipment that can be helpful is drinking water, fuel containers, chainsaws, fence pliers, water hoses, axes, and weather instruments.

Ignition equipment

Matches or a lighter should be taken to every burn, whether for starting or fighting a fire (removing fuel is one of the most effective ways to stop a wildfire). 

Drip torch being used to ignite fire during a prescribed burn

A drip torch probably is the most useful and widely used ignition tool on prescribed burns. Drip torch fuel typically is a mixture gasoline and diesel with 20-50 percent gasoline depending upon air temperature and fuel conditions. Additional pre-mixed drip torch fuel generally is brought to a burn in spark and rupture-resistant containers, which allows drip torches to be quickly refilled.

Other ground ignition devices include fusees or road flares, propane torch, terra torch , and delayed ground ignition devices. Large burns sometimes are ignited with aerial equipment such as a helitorch or delayed aerial ignition devices (DAIDS).

Fire suppression equipment

Pesticide sprayer and tractor used for fire suppression during prescribed burns

The most important fire suppression equipment is some type of water sprayer or pumper unit. All burns should have at least one power water sprayer present. Power sprayers can be traditional fire trucks, spray units mounted on skids, herbicide or livestock sprayers, ATV sprayers, etc. Spray units can be powered by gasoline motors, electric motors, or by power take-off (PTO) units. Power sprayers should be checked out, confirmed fully functional and filled with water prior to a burn. Spray units should always be started and left running so they are ready to use before the fire is ignited.

Other tools that can be useful for suppressing fire are: leaf blowers, rakes, swatters, and shovels. Leaf blowers can be used to extinguish fire in tree leaves or short grass, as well as mop-up along the edge of the fire line. Rakes also work well to extinguish low intensity fires and mop-up. Burning materials always should be blown or raked into the burned area.

Communication equipment

The fire boss should have a mobile telephone that can be used to call for assistance if problems develop. Where signal reception is adequate on larger burns, fire crews may use mobile telephones for internal communication. The best and most reliable communication equipment used by fire crews is two-way radios. Make sure the two-way radios provide adequate communication links on large burns where distance or topography interfere with signals.

Personal protective equipment

Appropriately dressed fire crew member igniting backfire during a prescribed burn

Every member of a burn crew should be dressed in clothing that is fire-resistant, including pants, shirts, jackets, boots, gloves, and hats. Clothing should be made of natural fibers such as 100% cotton or fire-resistant material like Nomex. Natural fibers do not burn or melt easily nor do specialized synthetic fire-resistant materials. Shirts should be long-sleeve and pants should be free from holes, rips or tears. Safety glasses or goggles are also very helpful to reduce heat on the face and protect the eyes from airborne particles. Apparel made from polyester and nylon, tennis shoes and open toe shoes are inappropriate for burns.

Other equipment

 

 

Drinking water is essential for most burns, and especially on growing season burns to keep the fire crew well hydrated. Spark and rupture-resistant containers with extra fuel for power sprayers, extra oil-fuel mix for leaf blowers or chainsaws are usually brought to a burn when their associated equipment is present. When burning in timber or near trees, chainsaws, pole saws, and or axes can be necessary to address burning snags or burning portions of live trees near firebreaks. Fencing pliers, wire cutters, or bolt cutters can be very helpful to quickly access a spot fire across a fence. Water hoses may be necessary to refill water tanks from the nearest available spigot. Weather meters, such as Kestrel pocket weather meters, can be useful to monitor actual, on-site weather conditions before, during, and post burn.

Fire Ecology in Aspen Forests

By Paul Rogers, Utah State University 

Aspen has conventionally been thought of as “fire dependent,” meaning that it requires forest fires to thrive. The quick-sprouting root system of an aspen clone  rapidly regenerates after all types of disturbance (i.e., landslides/avalanches, insects, disease, drought, tree harvest) including burning. Moreover, recent discoveries of high genetic diversity in aspen communities and common occurrences of seedling (sexual reproduction) establishment following fire is leading practitioners to question traditional aspen management. Fire suppression during recent decades is thought to be partially responsible for long-term aspen decline, however several experts have questioned this assertion. Likely, there are several causes for the lack of fire, most notably long periods of climatic moisture that increased the number of conifer trees in some aspen forests over the past century. Stable (nearly pure) aspen is much less conducive to wildfire or prescribed burning; rejuvenation in these forests is dependent on more continuous, low-level, tree mortality and regeneration.

Use of fire for restoration is a viable means of reducing conifers and promoting aspen suckers and seedlings in seral forests. Where disruption of fire cycles due to past fire suppression is evident, using fire to restore aspen is recommended.  Some managers favor a combination of harvest and burning, particularly where the possibility of escaped fires can damage property.

Further Reading

Krasnow, K. D. and S. L. Stephens. 2015. Evolving paradigms of aspen ecology and management: impacts of stand condition and fire severity on vegetation dynamics. Ecosphere 6:1-16.
Kulakowski, D., T. Veblen, T., and S. Drinkwater. 2004. The persistence of quaking aspen (Populus tremuloides) in the Grand Mesa area, Colorado. Ecological Applications 14:1603-1614.
Kurzel, B. P., T. T. Veblen, and D. Kulakowski. 2007. A typology of stand structure and dynamics of Quaking aspen in northwestern Colorado. Forest Ecology and Management 252:176-190.
Long, J. N. and K. Mock. 2012. Changing perspectives on regeneration ecology and genetic diversity in western quaking aspen: implications for silviculture. Canadian Journal of Forest Research 42:2011-2021.
Rogers, P. C., S. M. Landhӓusser, B. D. Pinno, and R. J. Ryel. 2014. A Functional Framework for Improved Management of Western North American Aspen (Populus tremuloides Michx.). Forest Science 60:345-359.
Shinneman, D. J., W. L. Baker, P. C. Rogers, and D. Kulakowski. 2013. Fire regimes of quaking aspen in the Mountain West. Forest Ecology and Management 299:22-34.

How wide should a firebreak or fireguard be?

There is no set standard, but it should be wide enough for the fuels along the boundary of the burn unit. Typically a bareground line 4 to 10 feet wide is sufficient, but narrow cow trails and even mowed lines can be safely used. The width of the firebreak can be offset by reducing the amount of fuel right next to the edge of the burn unit by mowing or shredding to diminish flame heights and fire intensity.

Weather Conditions for Controlled Burns

Although controlled burns can be conducted under pre-determined weather conditions, burns can be unsafe if the experience of the burn boss and crew is inadequate.

People new to burning should consider using the 60:40 rule. The 60:40 rule refers to restricting burn conditions to air temperatures less than 60 degrees Fahrenheit and relative humidity (Rh) greater than 40% with a wind speeds of 5-15 mph measured at 6 feet above the surface of the ground.

Rule of Halves

The rule of halves is an easy way to remember how to predict changes in fire behavior when the weather changes. When the air temperature increases by 20 degrees Fahrenheit, the relative humidity decreases by 50%. For example, if the air temperature changes from 60 degrees Fahrenheit with 40% relative humidity to 80 degrees Fahrenheit, the relative humidity will change from 40% to 20%, making the spotfire risk increase dramatically. In most cases, do not burn if there is a forecasted frontal passage or wind shift within 12 hours.

Weather Tools

There are many weather tools available. Make sure and check the wind direction, speed, temperature and relative humidity a few days before the burn, and right before the burn. It is very helpful to take notes of weather conditions during the burn. This can help people learn how to predict fire behavior in the future. On-site weather meters can be very helpful in taking up-to-date weather.

If conditions are not correct, including all parts of the prescription, do not start the fire. If the fire is not going well, put it out. Do not leave the fire until it is completely out, which means no smoke detected for at least one hour.

View this fact sheet for more detailed weather information regarding spotfires: http://pods.dasnr.okstate.edu/docushare/dsweb/Get/Document-2704/NREM-2878web.pdf

Conducting Prescribed Fires: A Comprehensive Manual

Conducting Prescribed Fires: A Comprehensive Manual, is a book that was written to fill a gap in fire literature and provide new and experienced prescribed fire practitioners alike with information about conducing prescribed fires. The book is a step-by-step guide for people interested in implementing prescribed fire. There are chapters in the book that will assist with the reasoning behind the use of fire and associated social elements. These chapter titles include why burn, law and liability, fire policy and public relations. Further into the book, the reader is guided through the burning process with fire weather, prescriptions, fire plans, safety and firebreaks are. The book then goes into the equipment needed and the how-to of conducting a prescribed burn with a variety of techniques. Important sections on smoke management and post-burn mop-up are also included.

Conducting Prescribed Fires also has over 90 photos and illustrations to help convey the message to the reader. This book has been written through years of practical experience and conducting prescribed fires under varying vegetation types and weather conditions. This book benefits people who are interested in burning a small pasture or an experienced land manager who uses fire.

Conducting Prescribed Fires: A Comprehensive Manual is available from Texas A&M University Press at http://www.tamupress.com/product/Conducting-Prescribed-Fires,5226.aspx

The Effects of Fire Video Now Available

Do you wonder how fire impacts the native plant communities around you? The new video titled “The Effects of Fire” VT-1139, produced by Oklahoma State University Agricultural Communications Services and Natural Resource Ecology and Management extension faculty, will help answer many of your questions.

The first chapter of the video covers the historical importance of fire prior to European man’s westward settlement. The video is then separated into three chapters including grasslands, shrublands and forests. Within each chapter the impacts and response of key plant species to fire within each plant community are examined. For example, in the forest section, impacts of fire on shortleaf pine (Pinus echinata) and Post Oak (Quercus stellata) are shown through a series of clips with 4-year, 3-year, 2-year and annual burning. This not only shows the impact on the trees, but also how the fire affects the understory herbaceous plant community. Throughout the video the effects of fire frequency or how often an area is burned has on the vegetative plant community and structure is shown to the viewer. The video addresses how season of burn also impacts each of the plant communities. Also highlighted within the video are interviews with fire ecologists and specialists describing the importance of fire to these native plant communities. If you are interested in livestock production, wildlife or just the enjoy the land this video will provide an increased awareness of the importance of fire. “The Effects of Fire” video is an important tool for anyone who currently uses fire to manage the land or is thinking about applying fire on their property. The video is closed captioned and has Spanish sub-titles. As an added feature of the video there are 20 pdf fire publications included on the video that cover a range of topics including prescribed burn associations, conducting prescribed fires and fire prescriptions,  and many more. The Effects of Fire video is available for purchase online at: https://secure.touchnet.com/C20271_ustores/web/product_detail.jsp?PRODUCTID=1245

If you would like to watch two chapters of the video as it was presented on OSU’s Sunup TV in January of 2012 visit the following link:

http://www.youtube.com/watch?v=xh7_onVw8PQ&feature=plcp

Fuel Mixtures for Drip Torches

Drip torches are a great tool to light prescribed fires. They are relatively light and they allow a person to be more mobile than with many propane torches. 

Mixing Drip Torch Fuel

Drip torch fuel is a mixture of diesel fuel and gasoline. Gasoline helps carry the flame from the drip torch to the ground, diesel fuel provides a longer, residual burn time.

When mixing fuel in drip torches, use 50% diesel fuel to 50% gasoline, in average (mild) temperatures. When temperatures are hotter, bump up the ratio to 60:40 or in very hot conditions, 70:30. This is done because when temperatures are high, gasoline tends to flare-up or burn too quickly, so increasing the ration of diesel fuel helps to keep the flame lit longer and reduce flareups.

When lighting at a fast pace such as from a vehicle, use a higher diesel mixture as well. This will make sure the flame is continuous. When in doubt, use slightly more diesel rich mix.

 

Types of Fire

There are many different techniques that can be used when lighting prescribed fires. The types of fire produced depend upon ignition technique and direction of the wind. These different types of fire are used in different areas of the burn depending on the conditions and objectives. The different types of fire include backfire, flank fire and head fire.

This image depicts the parts of a fire.

Types of Fire

A backfire is when you light off of a fire line and the flames burn into (against) the wind. Backfires are frequently used to create a line of “black,” or burned fuel, on the downwind side of the burn unit prior to lighting the flank or head fire. Backfires burn slowly and typically have short flame lengths.

A flank fire is a fire that burns perpendicular to the wind direction. Flank fires are commonly used after a backfire has been lit and let burn a safe distance, and prior to ignition of the head fire. Flank fires burn more quickly than backfires and the flames are greater in length.   

A head fire is created when the fire burns with the wind, pushing the fire towards the un-burned fuel. Head fires are used when there has already been a backfire lit on the downwind side of the burn, and flank fires lit, or if you are burning towards an area such as a large body of water, or previously burned unit with no remaining fuel. Head fires move quickly and typically have longer flame lengths than the other types and can produce intense heat.

Ignition Techniques

A strip backfire is when you light multiple lines of backfires, usually just 5-15 yards apart. This is commonly used to speed up the process of putting in “black” or burned area prior to flank or head fires.

Strip flank fires are less common, because they can turn into a “running flank fire” if the wind direction changes, and can be dangerous for the burn crew. If this technique is used, the people igniting should be alert and aware of any wind shifts.

Ringing a burn unit, is when the perimeter of the entire burn unit is lit off at once. Ringing a burn unit is not as common as other ignition techniques, and is usually only done in a small burn unit. This is a very quick method of burning because the flames from each side of the burn unit feed off of each other and suck together, but if the wind switches it can easily cause an escape. This should only be done by very experienced burn bosses and crews.

The most common process of lighting a prescribed fire begins when the backfire is lit off of the downwind fire line. Once there is a safe amount of black, a person on each side of the unit will uniformely ignite the flank fires. When they reach the respective head fire area of the unit, they pause to monitor the amount of fuel that the back and flank fires have burned. When there is a sufficient amount of “black” or burned area, the two will wither ignite the headfire from both corners and meet in the middle, or one person will ignite the head fire.

Every burn plan and ignition type is different. Use what works best for the burn unit, crew and available equipment.