Fuel Reduction Options for Landowners at the Wildland-Urban Interface
Introduction
The wildland-urban interface (WUI) can be defined as the area
where homes and entire communities are built within or adjacent
to wildfire-prone areas. A major issue in the southern WUI is
the loss of homes and other structures to wildland fire. Fire
is an important and necessary ecological process in many natural
areas of the southern United States. One ecological function
of fire is the reduction of grasses, shrubs, vines and small
branches that are the main vegetative fuels for fires. Both
living and dead plant materials burn, and in many southern forests,
substantial amounts of such vegetation accumulate every five
to six years. Periodic wildfires historically burned through
many Southern natural areas more frequently than that and effectively
reduced the vegetation accumulation.
As more homes are constructed within the WUI, the periodic fires that reduced fuel accumulations are being suppressed to reduce risk to structures and to reduce hazard and liability issues associated with smoke. Ironically, this suppression allows vegetation to grow unchecked and create dense vegetation that is capable of supporting intense fires, in turn increasing the risk of structural damage by wildfires. No fire control agency or local government has the resources to reduce high accumulations of vegetation in natural areas surrounding every home in the WUI; therefore, in most situations individual landowners must assume some responsibility for reducing this risk.
Fuel reduction around structures will greatly reduce the risk of damage caused by wildfire and several options exist for reducing fuel buildups in natural areas. Prescribed fire, which mimics historic natural fires, is one option; however, in many situations its use is not acceptable to neighbors and local governments in the WUI due to the potential of the fire escaping or of smoke causing hazardous conditions for nearby airports, hospitals, homes, and roads. Alternative methods for fuel reduction include herbicides, mechanical thinning, mowing and chopping, or livestock grazing, which may or may not be more acceptable to nearby homeowners.
The University of Florida (UF), in partnership with the Center, conducted a review of fuel reduction options available to small landowners; the findings of the detailed report are summarized below. In addition, UF initiated a research study to compare the effectiveness, longevity and costs of three fuel reduction treatments in the South. This study is summarized below as well.
Fuel Reduction Options Technical Report
The primary goal of the report was to investigate fuel management
techniques that are suitable for small landowners living in
the wildland-urban interface. Prescribed fire, herbicide treatments,
mechanical treatments, and the utilization of livestock for
fuel reduction were each reviewed based on the available literature
for their effectiveness and associated costs. A summary of each
technique follows:
- Reduces live and dead fuels effectively for one to several years. However, many problematic species resprout following fire.
- It is necessary to repeat every 2 to 4 years for long-term effectiveness.
- Prescribed burning permits are required.
- Cost for contractor to conduct prescribed fire: $15-$50 per acre.
- Cost for State to conduct prescribed fire: $10-$20 per acre.
Herbicide treatment
- A single treatment provides long-term live fuel reduction, but the effect on total vegetative fuels is not immediate since the dead plants remain until they decay.
- Follow herbicide with burning or chopping to reduce dead vegetative fuels sooner after herbicide treatment.
- Some local restrictions and licensing may be required for applications of certain herbicides. Check with your county extension agent.
- Cost to purchase herbicide application equipment: $30-$150 (not including cost of herbicide).
- Cost to purchase herbicide: $55-$450 per gallon.
- Cost for contractor to apply herbicides: $70-$150 per acre (includes herbicide).
Thinning trees
- Reduces live fuels effectively, but can increase downed trees or limbs unless they are harvested or burned.
- Thinning treatments remain effective for one to several years. However, problematic understory species may become established following cutting.
- Couple thinning with prescribed fire or herbicide for long-term effectiveness.
- Cost for contractor to thin: $100-$170 per acre.
- Cost for State to thin: $60-$100 per acre.
Mowing and chopping understory vegetation
- Reduces live and dead fuels effectively for one to several years. However, many problematic species reprout following mowing.
- Repeat every 1 to 3 years for long-term effectiveness.
- Cost for mowing and chopping: $100-$500 per acre.
Grazing
- Effective for reducing grasses and other herbaceous fuels, but does not reduce some shrubs or dead wood, such as branches and logs, effectively.
- Fuel reduction is short-term since many problematic species resprout following grazing. It is necessary to repeat every 1 to 2 years for long-term effectiveness.
- Cost to rent livestock: varies by area and type of animal (sheep, goats, or cattle).
- Cost for purchasing own herd: $200-$500 per head (not including maintenance, fencing, etc.). However, the costs can be offset by revenue gained from selling livestock such as cattle.
This comparison of fuel reduction options is a very simplified
summary of the information in the full report. The full report
provides cost estimates for each of the fuel reduction options,
extensive information on results obtained in multiple studies,
special considerations of ecological benefits or costs associated
with each treatment, and discussion of the main methods for applying
each treatment. By equipping owners of small parcels with information
regarding fuel management techniques, the report facilitates informed
decision-making about fuel reduction options. If you are considering
fuel reduction treatments on your land, please refer to the full
technical paper, which is available at:
(http://www.interfacesouth.org/products/pdf.php?id=2912).
Fuel Reduction Options for Landowners Study
This study is being conducted to assess the ecological and
cost effectiveness of different fuel reduction treatment options
for small landowners in the southern WUI. Fuel management treatments
include prescribed fire, herbicide treatments, and mechanical
treatments; untreated plots were also included for comparison
with the treatments.
This field investigation is being conducted in Alachua County, Florida. Measurements taken on each experimental treatment and untreated plot included percent cover, density and height of gallberry (Ilex glabra), saw palmetto (Serenoa repens), and wiregrass (Aristida beyrichiana), which are abundant shrub and grass species throughout much of the southern Coastal Plain region. Each of the four treatments was applied to different experimental plots in 2002 and the cost associated with each treatment was estimated (see Table 1). The effectiveness and longevity of fuel reduction for each treatment will be compared by re-measuring the variables for each species two times each year for several years.
Table 1.Cost comparison of fuel reduction options (2002).
Treatment | Cost per Acre |
Prescribed Fire | $50 |
Herbicide | $87 |
Mechanical Mowing | $150 |
Control | $0 |
Summary
In most situations WUI landowners must assume some responsibility
for reducing the vegetative fuels around their homes to reduce
fire risk on their property. In order to lessen the fuel reduction
burden on state and local governments and reduce the risk of
catastrophic fires in WUI communities, it is necessary to educate landowners
about fuel reduction and the options available for management
of vegetative fuels. The fuel reduction options report and
research
study provide this type of educational information and will
contribute to reducing human and property casualties resulting from fires
in the wildland-urban interface.
Links to Additional Information about Fire in the Wildland-Urban Interface:
-
Wildfire Risk Assessment Guide for Homeowners in
the Southern United States - See this
guide to determine whether your property is at risk
of damage
from wildfires. It is available in three formats:
- Download and print as a PDF: http://www.interfacesouth.org/fire/WildfireRAGH.pdf
- View interactive online version: http://www.interfacesouth.org/products/wildfire_ra.html
- Order full color print version: Add
to Cart
- Preparing a Firewise Plant List for WUI Residents - Use
this fact sheet for making local firewise plant lists
that can assist local homeowners with firewise landscaping.
It is available in three formats
- Download and print as a PDF: http://www.interfacesouth.org/products/fact_sheets/Preparing_Firewise_Plant_List.pdf
- View interactive online version: http://www.interfacesouth.org/products/flammability_key.html
- Order full color print version: Add
to Cart
- Reducing Wildfire Risk While Achieving Other Landscape
Goals - See this fact sheet to learn how to
achieve multiple goals with your firewise landscaping.
This
fact sheet is available in two formats:
- Download and print as a PDF: http://interfacesouth.org/products/fact_sheets/Reducing_Wildfire_Risk.pdf
- Order full color print version: Add
to Cart
- Selecting and Maintaining Firewise Plants for Landscaping -
Download this fact sheet to learn to choose and maintain low flammability plants for your firewise landscape. This fact sheet is available in two formats:- Download and print as a PDF: http://www.interfacesouth.org/products/fact_sheets/Selecting_Maintaining_Firewise_Plants_Landscaping.pdf
- Order full color print version: Add
to Cart
- Understanding Fire Behavior - See this fact sheet
for an in-depth description of how and why wildfires burn.
http://edis.ifas.ufl.edu/FR138
- Considering Fire in Florida's Ecosystems - Download this fact sheet to learn about the fire hazards for nine Florida ecosystems. http://edis.ifas.ufl.edu/pdffiles/FR/FR13700.pdf