See Tom’s Blog for narratives of burns of recent years.

Summary of Burns Carried out at Pleasant Valley Conservancy

Most of the 140 acres of Pleasant Valley Conservancy have been burned at one time or another, and many areas are burned annually. The table below provides a brief summary.

AreaUnitsType of habitatCharacterFrequency of burnsNotes
Barn Prairie0.8 acresPlanted 2001Wet mesicAnnual ( spring or fall)Formerly cropped
Crane Prairie3 acresPlanted 2005Wet mesicAnnual (usually spring)Wooded marsh edge restored
North-facing slopeUnits 15, 16, 17WoodlandMesicBiennially (seven times since restoration began in 1998)Last burned fall 2014
Pocket Prairie4.5 acresPlanted 1999Dry mesic to wet mesicAnnual (usually spring)CRP
Ridge Prairie2 acresPlanted 2005Dry mesicAnnual (usually spring)CRP
East Basin5 acresPlanted 2009Dry-mesic to wet-mesic prairie; partly open savannaAnnual (usually spring)Major tree removal in 2008
SavannaUnits 8, 10, 11, 12, 18, 19, 21Restored savannasDry mesic to mesicAnnually (fall or spring)Bur oak and white oak savanna
South-facing slope1, 2, 3, 4, 5, 6, 7, 9, 23Prairie and savanna remnantDry mesicAnnual (spring)Short to tallgrass prairie grading into bur oak savanna
Toby’s Prairie3.5 acresPlanted 1998Dry mesicAnnual (spring)CRP
Valley Prairie4 acresPlanted 2002Dry mesic to wet mesicAnnual (usually spring)CREP
Wetland40 acresMarsh, sedge meadow, shrub carr, stream bankWet (standing water) or wet mesicWhole wetland in 2005, 2010, 2013; small parts occasionallyMajor effort; expensive
Woods thru service road areaUnits 20, 21Prairie, savanna, and woodlandDry-mesic to mesicAnnually (usually spring)Restored 2002; part faces steep ravine
North-facing oak woodsUnits 15, 16, 17Oak woodsCool, mesicBiennially in fall on even yearsRed oak forest; spring ephemerals
CRP: Conservation Reserve Program; CREP: Conservation Reserve Enhancement Program

20-year burn history

The table below provides a unit-by-unit summary of burns between the years 1997 (when the first burn was held) and 2017. Spring and fall burns are separated and vegetation types are shown. The numbers in some of the cells are the designations of individual management units. North woods (Units 15 and 16) has been burned biennially from 2006 thru 2016 and parts again in the spring of 2017.

YearSeasonSouth slopeRidge-top savannasWhite-oak savannas<<<<<Unit 13 + TriangleUnits 20 + 21North woods
1997Spring1 only           
1998Spring7-Jan12B Toby N 1/2        
1999Spring1-4, 6-711, 12B  Pocket (August)Valley (Brome)      
1999Fall           15 +16
2000Spring1-6, 238, 10, 1112BToby N+S        
2000Fall 11          
2001Spring2-7, 9, 238, 10 Toby N+S        
2001Fall 19          
2002Spring1-7, 9  Toby N+S Valley (after glypho)Barn     
2002Fall 8, 10, 1912AB      Tri  
2003Spring1-7, 9, 23  Toby N+SPocket Barn    17 (part) with Toby
2003Fall 8, 10, 11, 1912AB +18         
2004Spring1-7, 9, 23  Toby N+SPocket Barn  13 + Tri20 + 2117 (part) with Toby
2004Fall 8, 10, 1112AB+18   Barn     
2005Spring1-7, 9, 23  Toby NPocketValley   1320 + 2117 (part) with Toby
2005Fall      Barn  Tri  
2006Spring6-7, 238, 10, 11A-C, 19B12ABToby SPocket (W 2/3)    13 + Tri  
2006Fall 8, 10, 1112B+18  ValleyBarn     
2007Spring1-7, 9, 2311D, 19C-E12A+18Toby N+SPocket    13 + Tri20 + 2115+16
2007Fall        Crane   
2008Spring1-7, 9, 238, 10, 11, 19B-E12AB+18Toby N+SPocketValley   Tri20 + 21 
2008Fall   Toby N+SPocketValley (partial)   Tri 15+16+19A
2009Spring1-7, 9, 238, 10, 11, 19B-E12AB+18Toby reburnedreburned PocketValley RidgeCraneTri20 + 21rebrned+17 (part)
2009Fall            
2010Spring1-7, 9, 238, 10, 11, 19A-E12AB+18Toby N+SPocketValleyBarnRidgeCrane13 + Tri20 + 21 
2010Fall 19A         15+16+19A
2011Spring1-7, 9, 238, 10, 11, 19A-E12AB+18Toby N+SPocketValleyBarnRidge + East BasinCrane13 + Tri20 + 21 
2011Fall      Barn Crane   
2012Spring1-7, 9, 238, 10, 11, 19A-E12AB+18Toby N+SPocketValley + Nearby WetlandBarnRidge + East BasinCrane13 + Tri20 + 21 
2012Fall 19A      Crane  15+16
2013Spring1-7, 9, 238, 10, 11, 19A-E12AB+18Toby N+SPocketValley + Nearby WetlandBarnRidge + East BasinCrane13 + Tri  
2014Spring1-7, 9, 238, 10, 11, 19A-E12AB+18Toby N+SPocketValley + Marsh stripBarnRidge + East BasinCrane13 + Tri20 + 21 
2014Fall           14 +15+16 + Quarry
2015Spring1-7, 9, 238, 10, 11, 19A-E12AB+18Toby N+SPocketValley + Nearby WetlandBarnRidge + East BasinCrane13 + Tri20 + 21 
2016Spring1-7, 9, 238, 10, 11, 19A-E12AB+18Toby N+SPocketValley + Nearby WetlandBarnRidge + East BasinCrane13 + Tri20 + 21 
2016Fall           14 + 15+16 + 17 +Quarry
2017Spring1-7, 9, 238, 10, 11, 19A-E12AB+18Toby N+SPocketValley + Nearby WetlandBarnRidge + East BasinCrane13 + Tri20 + 21 
2017Fall           16 +17
2018Spring1-7, 9, 238, 10, 11, 19B-E12AB+18Toby N+SPocketValley + Nearby WetlandBarnRidge + East BasinCrane13 + Tri20 + 21 

March 2019 burns

After a cold early March, the weather improved and over 4 days we were able to get lots of our big burns done. Over 80 acres, as shown on the map. Only the North Woods and Wetland remain to be burned.

Why do we burn?

One of the most important management tools in restoration ecology is fire.

Fire is a natural element in the ecosystem, and under appropriate conditions may develop spontaneously as a result of lightning strikes. Lightning-caused fires occur mainly during warm windy dry conditions and hence occur rather randomly. However, tree ring studies have shown that most oak savannas were burned frequently, generally every few years.

Imitating nature, humans throughout the world have used fire for thousands of years. In North America, fire was used by Native Americans to encourage berry production, expose acorns for collection, prepare planting sites, control undesirable pests, fireproof villages, create and maintain open woodlands and savannas, concentrate game, and help maintain trails. Fires were ignited in the dormant season, either in spring, before plants had started to grow, or in fall, after frosts had killed above-ground parts of plants.

When European settlers displaced Native Americans, the use of fire continued, for many of the same reasons. In the hill country of southwestern Wisconsin, farmers continued to use fire to keep grazing land from getting choked with brush and weeds. Early spring burns encourage the growth of grasses by removing detritus and debris, and by top-killing shrubs.

However, the 20th century introduced the era of “fire suppression”, which as we now know was misguided. It was eventually understood that fire suppression was having unintended consequences, destroying the values that prairies and oak forests provided, and replacing native habitat with undesirable trees and shrubs. It was not until the 1980s that fire was seriously reintroduced as a management tool for oak savannas and woodlands, introducing what the U.S. Forest Service calls the “fire management era”. “The Fire Management era is generally characterized by a major shift from fire suppression to a period of increasing knowledge and understanding of fire ecology and the response of varied ecosystems to altered fire regimes.”

A typical prairie/savanna burn on the south-facing slope at Pleasant Valley Conservancy. The two photos were taken at the same location (note the small double tree in the middle). The burn was done on March 19. The photo on the left was taken on September 13, 2019

Prescribed Fire

The term “prescribed fire” refers to fires that are set on purpose according to a written and approved plan, the prescription. The plan describes the objectives of the burn and the expected results. The burn plan specifies, either in words or by a map, the parcel of land to be burned, the landowner(s), and owners of adjacent land not included in the burn. Any considerations of smoke management are identified. The burn plan specifies the required governmental permits and lists those who must be notified on the day the burn is to take place. The locations and characteristics of all fire breaks are given, as well as strategies for the containment of fire within the burn unit. Any preparations of the burn unit needed before the burn can take place are indicated, including a list of fire-sensitive elements within or near the burn unit that must be protected. The burn plan should state the personnel needed, as well as their qualifications and duties. The burn plan also lists the equipment needed to conduct the burn.

In Wisconsin, prescribed fire is now a critical management tool for organizations such as The Nature Conservancy, The Prairie Enthusiasts, Pheasants Forever, and the Wisconsin Department of Natural Resources. Many private landowners also use prescribed fire on a regular basis. The U.S. Department of Agriculture, through its Natural Resources and Conservation Service, strongly promotes the use of prescribed fire in the management of private lands that have been dedicated to various soil and water conservation programs. The Wisconsin Prescribed Fire Council strives to make the use of fire in Wisconsin safer and more accepted. A number of commercial contractors carry out prescribed burns for landowners.

Even the forest industry now realizes that fire plays a major role in the oak forest, removing many weedy trees and shrubs. Prescribed fire removes the thin-barked shrubs and trees from the midstory and understory of the forest without harming the dominant oaks. Fire also consumes the litter, thus promoting the growth of grasses and forbs, and encouraging the regeneration of oak. Long-term research studies have shown that annual burns over a number of years gradually restore the oak savanna to its original state.

Prescribed burn in a bur oak savanna. Note how the fire hugs the ground. The principal fuel is oak leaves.

History of Fire Use at Pleasant Valley Conservancy

Pre-restoration burn history

According to oral reports, the farmers who had settled the Pleasant Valley Conservancy area (the Lockwoods) had used fire every year to encourage early “green up” of the grazing land. The south-facing slope as well as the white oak savannas surrounding the Pocket Prairie were burned. There is photographic evidence that the south-facing slope was treeless, which would only occur with frequent fire.

After landowner Harold Lockwood died in the 1950s, the land fell into absentee ownership, and fire was no longer carried out.

Early restoration burns

Fire was introduced to Pleasant Valley Conservancy soon after restoration work began in 1997. The first burn was a small one (about 0.5 acre) carried out on the Unit 1 remnant. This was successful and the prairie responded dramatically.

In 1998 the first major burn was done by The Prairie Enthusiasts. The two prairie remnants burned well but most of the south slope burned poorly or not at all. The following day Kathie returned to the south slope with a drip torch and carefully relighted the whole thing. The photo shows her in action.

The results were dramatic. The south-facing slope that had originally been heavily brushed in was opened up, prairie grasses began to flourish, and many prairie forbs appeared.

Kathie stripping the south-facing slope on 8 April 1998. The Prairie Enthusiasts had unsuccessfully tried to burn this slope the day before. After Kathie’s work, the slope responded dramatically with lots of prairie grasses and forbs.

Thus, beginning with two small prairie remnants of about 0.5 acre each (Units 1 and 4), the whole south slope eventually was restored and burned. In recent years, south slope burns of 20-25 acres have been carried out.

Present burn policy

Most of the upland areas are burned annually, generally in the spring although occasionally in the fall. Prescribed burns are our most important management tool, and are closely integrated into our invasive plant control program. Without prescribed burns, the control of invasive plants would be much more difficult and, in many places almost impossible.

The way we do them, burns do not harm wildlife. Midwestern wildlife evolved in a fire-prone environment and has adapted to fire. The larger animals are able to move away from fire. We burn in the dormant season of either early spring or late fall. No burn is 100% complete and smaller animals survive in the numerous refugia that remain unburned.

Burn refuges

Unburned areas always occur during prairie burns, and provide refugia for small animals. The photo here shows a typical example in the Crane Prairie. Refuges are even more common in savanna and woodland burns. Likewise, major unburned areas occur in wetland burns.

A prescribed burn of the south-facing slope was carried out in March 2003, after 5 years of restoration work. The principal fuel is little bluestem and Indian grass.

Starting in 1998, annual savanna burns have also been carried out. These burns have proceeded in tandem with control of brush and weedy trees. These burns of 50 or more acres of oak savanna or oak woodland are responsible for the high quality of the Pleasant Valley Conservancy oak habitats.

Burns have also been carried out in the north-facing oak woodlands. The first burn was done in the fall of 1999 and was very successful. The North Woods was burned again in spring 2007, fall 2008, spring 2009, fall 2010, fall 2012, fall 2014, and biennially since. Fall burns are the best for the north woods because of their aspect (N-facing). Occasionally the north slope is burned in the spring.

Lady slipper orchid (Cypripedium caleolus) growing out of the ashes of the fall burn of the north woods. A large number of these orchids developed in the spring after the burn, noticeably more than usually develop.

Each year using GIS we prepare a map of areas that were burned. The ones for the 2007-2008 and 2008-2009 burn seasons are shown below.

Burns were done in Fall of 2008 and Spring of 2009. Dates are shown on the labels.

The Burn Permitting System

Burn permits are required in our part of Wisconsin between January 1 and May 31. The rest of the year we can burn without a permit, although we must notify the local fire department (Black Earth Joint Fire District) that we will be burning. Therefore, we can carry out fall burns without a permit, but need one for spring burns. Our permits are issued by the Fire Control Ranger of the Division of Forestry of the Wisconsin Department of Natural Resources. Most of our burns are carried out between the middle of March and the end of April. (These permits are for daytime burns. Burns carried out after 6 PM can be done with a permit issued by the local fire warden.)

Every February we submit to the Ranger our spring burn plan. Based on this plan, our permits are issued, one for each burn in our plan. However, we must obtain oral authorization from the Ranger on the day of the burn. We reach the Ranger through the District Office in Dodgeville. Once we have authorization, we can proceed with the burn.

Note that although the prescribed burn program is administered through the Division of Forestry, it does not include only forests. Prairie and wetland burns are also regulated by the Forest Ranger.

Burn Equipment Used at Pleasant Valley Conservancy

We are well-equipped to carry out safe and effective prescribed burns.

Water Our electrically operated well provides an unlimited amount of water.

Pumper Units Kawasaki Mule (4 WD All Terrain Vehicle) with 65 gallon tank, 100 feet of hose, high-pressure hose nozzle, 5.5 HP Honda gasoline operated engine. An additional 200 feet of hose can be added if needed.

Backpack Water Sprayers We have six backpack water sprayers with special waistband harnesses. These 5-gallon units have brass slide-action hand-operated pumps. It is possible to spray precisely and accurately. This sort of unit is useful for putting out small (spot) fires or for controlling fires in areas inaccessible to ATVs or trucks.

Flappers We have two flappers for use in putting out small spot fires.

Drip torches We have three drip torches capable of dispensing fire (lighted fuel) along a fire line or throughout a burn unit. The tank is a heavy-duty aluminum canister with a specially designed fire nozzle equipped with a safety loop that prevents flashback. A check valve in the cover provides a second level of protection against flashback. The fuel is a mixture of 2 parts diesel and 1 part gasoline. Once lighted, the fire drips slowly out of the end.

Two-way radios We have ten wide-range two-way radios, each capable of reaching anywhere in the Conservancy. Our radios are Kenwoods that are capable of transmitting up to 6 miles, even over rough terrain and through smoke. Special hands-free harnesses are used.

Fire protective clothing We wear Nomex fire protective clothing.

Additional equipment from the Prairie Enthusiasts We can also borrow additional equipment from the Empire-Sauk Chapter of the Prairie Enthusiasts including more two-way radios operating on the same frequencies, more drip torches, more backpack water cans, and more flappers.

Mule pumper unit

Use of the drip torch
Worker equipped with fire-resistant jumpsuit of Nomex. The water can is mounted on a used knapsack frame.
Custom-made signs are used at the road corners to inform people of what is going on. If there is any danger of smoke blocking the road, personnel are assigned to control traffic.

Burn photographs