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John Blanton, Forest SilviculturistJohn Blanton, Forest SilviculturistUSDA Forest ServiceUSDA Forest Service
Asheville, NCAsheville, NC
Upland Hardwood Silviculture TrainingUpland Hardwood Silviculture TrainingBent Creek Experimental ForestBent Creek Experimental Forest
July 23, 2007July 23, 2007
We will discuss 500 years of We will discuss 500 years of disturbance on 37 million acres in the disturbance on 37 million acres in the Southern Appalachians;Southern Appalachians;
Discussion is based upon available Discussion is based upon available literature, notably, the 1996 literature, notably, the 1996 Southern Appalachian Assessment; Southern Appalachian Assessment;
Thanks to Dr. Scott Schlarbaum, Thanks to Dr. Scott Schlarbaum, Professor of Forestry at Univ. of TN at Professor of Forestry at Univ. of TN at Knoxville, for his assistance and Knoxville, for his assistance and additional slides.additional slides.
Occurrence of disturbances is irregular in both space Occurrence of disturbances is irregular in both space and time.and time.
Fire History Reconstruction, Brush MountainFire History Reconstruction, Brush Mountain
MEI: 4 yrs
LEI: 1yr
UEI: 8 yrs
82% Dormant Season Fires
Importance of understanding Importance of understanding
disturbance historydisturbance history Human activities can cause or postpone Human activities can cause or postpone
certain types of disturbance.certain types of disturbance.
Disturbances will always occur across Disturbances will always occur across the landscape at varying intervals.the landscape at varying intervals.
The forests we have today are a result The forests we have today are a result of past disturbances or lack of them.of past disturbances or lack of them.
Causes of disturbance: FireCauses of disturbance: Fire
2000 & 2002: 7 million acres burned each year
Average of 6 lightning fires/million acres occurs in SA’s
May 2003: 400 tornadoes in one weekMay 2003: 400 tornadoes in one week
Since 1871: 14 hurricane-related windstorms in Southern AppalachiansSince 1871: 14 hurricane-related windstorms in Southern Appalachians
Causes of disturbance: WindCauses of disturbance: Wind
With an aging, even-aged forest, the percentage of With an aging, even-aged forest, the percentage of windthrow will increase (oak decline, heart rots)windthrow will increase (oak decline, heart rots)
Causes of disturbance: WindCauses of disturbance: Wind
Blowdown of individual trees: Perhaps 4-6% of acres could be Blowdown of individual trees: Perhaps 4-6% of acres could be affected in 200 years, including single treefallsaffected in 200 years, including single treefalls
Causes of disturbance: WindCauses of disturbance: Wind
Causes of disturbance: WindCauses of disturbance: Wind
Hurricane Hugo – 1989: high winds, microbursts in mtns.Hurricane Hugo – 1989: high winds, microbursts in mtns. Opal – 1995: 8” rain, 60-80 mph in NC mountains Opal – 1995: 8” rain, 60-80 mph in NC mountains
Canopy gaps were 0.5-2.7 acres on Bent CreekCanopy gaps were 0.5-2.7 acres on Bent Creek Within gaps, 28% of trees windthrown, nearly all uprootedWithin gaps, 28% of trees windthrown, nearly all uprooted Black oak & scarlet oak most vulnerable to uprootingBlack oak & scarlet oak most vulnerable to uprooting At Coweeta, SO composed 6% density, but created 44% At Coweeta, SO composed 6% density, but created 44%
gapsgaps
Landslides - saturated soils on steep slopes
Hurricane Frances, 2004
Causes of disturbance: WaterCauses of disturbance: Water
Causes of disturbance: IceCauses of disturbance: Ice
Ice storms & wet snows (worse if vines are in trees)Ice storms & wet snows (worse if vines are in trees)
- 1993 blizzard: 24-48” snow, high winds, - 1993 blizzard: 24-48” snow, high winds, tornadoes in Easttornadoes in East
- 1994, southeast states ice storm: 9 deaths, $3 - 1994, southeast states ice storm: 9 deaths, $3 billionbillion
- Yellow-poplar, black cherry, & VA Pine very - Yellow-poplar, black cherry, & VA Pine very susceptiblesusceptible
Causes of disturbance: IceCauses of disturbance: Ice
Hail aloneHail alone
Hail + Hail + insectsinsects
Causes of disturbance: Native InsectsCauses of disturbance: Native Insects
Southern Pine Beetle: From 2000-Southern Pine Beetle: From 2000-2003,2003,
1.5 million acres in western NC1.5 million acres in western NC
Causes of disturbance: Native Causes of disturbance: Native InsectsInsects
SPB: 75% of pine on Daniel Boone NF in KY was killed
Causes of disturbance: Native InsectsCauses of disturbance: Native Insects
Red oak borer in Ozark Mtns.in 2002: Red oak borer in Ozark Mtns.in 2002: Populations over 18 adults/m2 of barkPopulations over 18 adults/m2 of bark 300-500 borer attacks per tree instead of the usual 10 attacks300-500 borer attacks per tree instead of the usual 10 attacks Oak decline on Ozark NF: 300,000 acres (over 400 sq mi) in Oak decline on Ozark NF: 300,000 acres (over 400 sq mi) in
20012001
Exotic forest Exotic forest pests in Eastern pests in Eastern
forestsforests
Chestnut Blight
Butternut CankerDisease
Dutch ElmDisease
Before
After
White and Black Oaks –White and Black Oaks – Gypsy Moth Gypsy Moth
Eastern White Pine –Eastern White Pine – White Pine Blister Rust White Pine Blister Rust
American Chestnut –American Chestnut – Phytophthora cinnamomiPhytophthora cinnamomi, , Chestnut Blight, Chestnut Gall Wasp, Asian Chestnut Blight, Chestnut Gall Wasp, Asian Ambrosia BeetleAmbrosia Beetle
Spruce (Eastern Hemlock) –Spruce (Eastern Hemlock) – Hemlock Woolly Hemlock Woolly AdelgidAdelgid
Tree species recorded by Tree species recorded by Naturalist John Bartram’s Naturalist John Bartram’s first trip (1749) through first trip (1749) through Pennsylvania and their Pennsylvania and their
exotic pests (2007)exotic pests (2007)
Sugar Maple –Sugar Maple – Pear Thrips, Asian Longhorned Pear Thrips, Asian Longhorned BeetleBeetle
Linden –Linden – Basswood ThripsBasswood Thrips
Pitch Pine –Pitch Pine – Pine Shoot Beetle, Sirex woodwasp Pine Shoot Beetle, Sirex woodwasp
Elm –Elm – Dutch Elm Disease (2 strains) Dutch Elm Disease (2 strains)
Beech –Beech – Beech Bark Disease Complex Beech Bark Disease Complex
White Walnut (Butternut) -White Walnut (Butternut) - Butternut CankerButternut Canker
Tree species recorded by Tree species recorded by Naturalist John Bartram’s Naturalist John Bartram’s first trip (1749) through first trip (1749) through Pennsylvania and their Pennsylvania and their
exotic pests (2007)exotic pests (2007)
Causes of disturbance: Exotic InsectsCauses of disturbance: Exotic InsectsGypsy moth: 80,000 acres of defoliation in Virginia in 2003Gypsy moth: 80,000 acres of defoliation in Virginia in 2003
The cumulative effect is alteration of forests as we know them today.
Causes of disturbance: Exotic Causes of disturbance: Exotic InsectsInsects
Hemlock Hemlock Woolly Adelgid: Woolly Adelgid:
Most hemlocks Most hemlocks will die within will die within the next 5 years!the next 5 years!
Causes of disturbance: Exotic DiseasesCauses of disturbance: Exotic Diseases
Chestnut BlightChestnut Blight Up to one quarter of the dominant Up to one quarter of the dominant
trees were chestnuttrees were chestnut 1904 to 1950: American chestnuts on 9 1904 to 1950: American chestnuts on 9
million acres diedmillion acres died
Causes of disturbance: Exotic Causes of disturbance: Exotic DiseaseDisease
Phytophthora cinnamomi:Phytophthora cinnamomi:
Chestnut ink diseaseChestnut ink disease - By - By 1824, great losses of 1824, great losses of American chestnut on American chestnut on poorly drained soils.poorly drained soils.
Littleleaf diseaseLittleleaf disease on on shortleaf pine on shortleaf pine on poorly drained, poorly drained, eroded clay soilseroded clay soils.
Causes of disturbance: AgeCauses of disturbance: Age
Oak Decline Oak Decline Complex:Complex:
(age, site (age, site productivity, productivity,
drought, insects, drought, insects, fungi, pollution):fungi, pollution):
Older, even-aged Older, even-aged forests (on N/P, forests (on N/P, 82% >60 years old)82% >60 years old)
Loss of vigor Loss of vigor predisposes trees predisposes trees to other agents to other agents
Two-lined Chestnut Borer Armillaria Root Rot
Causes of disturbance: DroughtCauses of disturbance: Drought
2002: $10 billion in damages in 30 states;1988: $40 billion in damages in central/eastern
US;1736, 1756, 1863, 1911, 1925, early-1930’s
(Dust Bowl), 1954, 1956, 1977
Periods of History:Periods of History:
Over 5,000 years ago, the climate Over 5,000 years ago, the climate continued to warm as the ice age continued to warm as the ice age
ended.ended.
Population of Native Americans Population of Native Americans increased over time to 10-12 million increased over time to 10-12 million
(mostly along major rivers).(mostly along major rivers).
Native Americans & the Native Americans & the North American North American
LandscapeLandscape
Native Americans & the Native Americans & the North American North American
LandscapeLandscape
Was the North American landscape undisturbed
when the Europeans began colonization?
Was the North American landscape undisturbed
when the Europeans began colonization?
Native Americans & the North Native Americans & the North American LandscapeAmerican Landscape
Native Americans & the North Native Americans & the North American LandscapeAmerican Landscape
Often viewed as nomadic hunter-Often viewed as nomadic hunter-gatherer tribes such as the gatherer tribes such as the
Lakotas (Sioux) in the Great PlainsLakotas (Sioux) in the Great Plains
Native Americans & the North Native Americans & the North American LandscapeAmerican Landscape
Native Americans & the North Native Americans & the North American LandscapeAmerican Landscape
In reality, there were a number of tribes In reality, there were a number of tribes with permanent villages, all dependent with permanent villages, all dependent
upon the surrounding land for food, upon the surrounding land for food, water, and shelter.water, and shelter.
In reality, there were a number of tribes In reality, there were a number of tribes with permanent villages, all dependent with permanent villages, all dependent
upon the surrounding land for food, upon the surrounding land for food, water, and shelter.water, and shelter.
Trees killed by Trees killed by firefire
Native Americans & the Native Americans & the North American North American
LandscapeLandscape
Native Americans & the Native Americans & the North American North American
LandscapeLandscapeAgriculture
Nomadic Nomadic Hunter – Gatherer Hunter – Gatherer
SocietySociety
Paleoindian PeriodPaleoindian Period10,000 BC – 8,000 10,000 BC – 8,000
BCBC
Paleoindian PeriodPaleoindian Period10,000 BC – 8,000 10,000 BC – 8,000
BCBC
Archaic PeriodArchaic Period8000 BC - 1000 8000 BC - 1000
BCBC
Archaic PeriodArchaic Period8000 BC - 1000 8000 BC - 1000
BCBC
Hunter–Hunter–Gatherer Gatherer
SocietySociety
Small VillagesSmall Villages
Village Gardener Village Gardener SocietySociety
Domestication of Domestication of plants including corn, plants including corn, sunflowers, squashessunflowers, squashes
Woodland PeriodWoodland Period1000 BC - 1000 1000 BC - 1000
ADAD
Woodland PeriodWoodland Period1000 BC - 1000 1000 BC - 1000
ADAD
Mississippian PeriodMississippian Period1000 AD - 1600 AD1000 AD - 1600 AD
Mississippian PeriodMississippian Period1000 AD - 1600 AD1000 AD - 1600 AD
Highly structured societyHighly structured societyDevelopment of large villagesDevelopment of large villages
Mississippian PeriodMississippian Period1000 AD - 1600 AD1000 AD - 1600 AD
Mound BuildersMound Builders
Mississippian PeriodMississippian Period1000 AD - 1600 AD1000 AD - 1600 AD
Mound BuildersMound Builders
Etowah Etowah MoundsMounds
circa 800 ADcirca 800 AD
Etowah Etowah MoundsMounds
circa 800 ADcirca 800 AD
54 acre site in northern 54 acre site in northern GeorgiaGeorgia
Fortified cities led by high Fortified cities led by high priestpriest
Mississippian PeriodMississippian Period1000 AD - 1600 AD1000 AD - 1600 AD
Mississippian PeriodMississippian Period1000 AD - 1600 AD1000 AD - 1600 AD
Substantial Substantial AgricultureAgriculture
Maximum influence around 1680, controlling Maximum influence around 1680, controlling most of the northeastern United States and most of the northeastern United States and
eastern Canadaeastern Canada
Iroquois Iroquois ConfederacyConfederacy
Iroquois Iroquois ConfederacyConfederacy
Hunter – Agricultural SocietyHunter – Agricultural Society
Iroquois Iroquois ConfederacyConfederacy
Iroquois Iroquois ConfederacyConfederacy
Planting the Three SistersPlanting the Three Sisters
Squash (700 BC), Corn (800 AD), Beans (1200 Squash (700 BC), Corn (800 AD), Beans (1200 AD)AD)
Iroquois Iroquois ConfederacyConfederacy
Iroquois Iroquois ConfederacyConfederacy
Historic PeriodHistoric Period1600 AD - Present1600 AD - Present
Historic PeriodHistoric Period1600 AD - Present1600 AD - Present
Hunter-Hunter-Agricultural Agricultural
SocietySocietyEastern Eastern
Tennessee and Tennessee and western North western North Carolina was Carolina was
occupied by the occupied by the Cherokee Nation; Cherokee Nation; the Chickasaws the Chickasaws
controlled controlled hunting rights in hunting rights in west Tennessee.west Tennessee.
Native Americans & FireNative Americans & FireNative Americans & FireNative Americans & Fire
Early explorers and trappers often observed Early explorers and trappers often observed huge burned over or cleared areas with many huge burned over or cleared areas with many
dead treesdead trees
Native Americans & Native Americans & FireFire
Native Americans & Native Americans & FireFire
Native Americans burned Native Americans burned parts of the ecosystem to parts of the ecosystem to
promote a diversity of promote a diversity of habitatshabitats
Native Americans & FireNative Americans & Fire
Purposeful fires differed from Purposeful fires differed from natural or accidental firesnatural or accidental fires
Native Americans & FireNative Americans & Fire
Purposeful fires differed from Purposeful fires differed from natural or accidental firesnatural or accidental fires
Seasonality of Seasonality of burningburning
Frequency of Frequency of burning burning certain areascertain areas
Intensity of Intensity of firefire
Native Americans used fire Native Americans used fire for:for:
Native Americans used fire Native Americans used fire for:for:
Driving big game to improve huntingDriving big game to improve hunting
Maintaining prairies or meadows for grass Maintaining prairies or meadows for grass production (basket grasses, grain foods, production (basket grasses, grain foods, habitat for grazing animals)habitat for grazing animals)
Clearing riparian areas to promote better Clearing riparian areas to promote better habitat for beaver, muskrat, moose, and habitat for beaver, muskrat, moose, and waterfowlwaterfowl
Felling trees and clearing wooded areas for Felling trees and clearing wooded areas for crop and berry productioncrop and berry production
Native Americans used fire for:Native Americans used fire for:Native Americans used fire for:Native Americans used fire for:
Favoring plants such as strawberries, Favoring plants such as strawberries, raspberries, and tobaccoraspberries, and tobacco
Protecting medicinal plants by maintaining a Protecting medicinal plants by maintaining a burned area around themburned area around them
Concentrating populations of insects for Concentrating populations of insects for collectioncollection
Reducing pests like black flies, ticks, fleas, Reducing pests like black flies, ticks, fleas, mosquitoes, rodents, and poisonous snakesmosquitoes, rodents, and poisonous snakes
Native Americans used fire Native Americans used fire for:for:
Native Americans used fire Native Americans used fire for:for:
Clearing brush and vines along travel routes Clearing brush and vines along travel routes and to increase accessibility into the forestand to increase accessibility into the forest
Depriving enemies of cover/ambush placesDepriving enemies of cover/ambush places
Signaling in war & announcing gatherings of Signaling in war & announcing gatherings of tribestribes
Driving enemies away or burning themDriving enemies away or burning them
Because burning was done frequently, fuel accumulations were low, and most fires burned only the understory, not killing the dominant trees.
Native Americans & FireNative Americans & Fire
Pre-European SettlementPre-European Settlement1492 AD until 1607 AD1492 AD until 1607 AD
Columbus, Ponce de Leon, Cortes, Verrezano, DeSoto, and other explorers introduced smallpox, measles,
typhus, and malaria to North America, resulting
in up to 90% mortality among Native American populations.
Villages were abandoned, and canebrakes and agricultural fields in river bottoms reverted to
forest.
Early European Settlement Early European Settlement 1607 until 1880 – A Closed-Canopy 1607 until 1880 – A Closed-Canopy
ForestForest
Early colonial settlers and exploratory Early colonial settlers and exploratory expeditions reported relatively complete expeditions reported relatively complete coverage of closed-canopy forests from coverage of closed-canopy forests from the Atlantic Coast westward to the Great the Atlantic Coast westward to the Great Plains.Plains.
The open conditions written about by the The open conditions written about by the early explorers like DeSoto were gone early explorers like DeSoto were gone except near the remaining Native except near the remaining Native American villages.American villages.
Early European Settlement Early European Settlement 1607 until 1880 – A Closed-Canopy 1607 until 1880 – A Closed-Canopy
ForestForest
Early colonial settlers began to clear the land for Early colonial settlers began to clear the land for agriculture harvest the forest to export wood to Europe, agriculture harvest the forest to export wood to Europe, as European forests had been exhausted of old growths as European forests had been exhausted of old growths or virgin timber. or virgin timber.
Many of the forest products exported were related to Many of the forest products exported were related to construction of naval ships. construction of naval ships.
As European settlers moved into the Southern As European settlers moved into the Southern Appalachians during the 1700’s, their approach to land Appalachians during the 1700’s, their approach to land management, including agriculture and timber harvest, management, including agriculture and timber harvest, was much more intense than those of Native Americans.was much more intense than those of Native Americans.
Colonial settlers received land from the Public Domain, Colonial settlers received land from the Public Domain, cleared forest land for pasture, exhausted the land and cleared forest land for pasture, exhausted the land and
moved westward repeating the same land clearing moved westward repeating the same land clearing procedures.procedures.
Colonial settlers received land from the Public Domain, Colonial settlers received land from the Public Domain, cleared forest land for pasture, exhausted the land and cleared forest land for pasture, exhausted the land and
moved westward repeating the same land clearing moved westward repeating the same land clearing procedures.procedures.
Abandoned Native American fields were sought out and cleared using tree girdling
and fire.
Early Early SettlementSettlement
This photo of a ‘deadening’ for sheep pasture was taken August 1, 1901 on White Top Mt. in Virginia by H.B. Ayres.
Cattle, hogs, and sheep ranged freely and in large numbers. John Muir called sheep ‘hoofed locusts’
Razorback hogRazorback hog
Annual burning of the mountain slopes became a standard practice to increase forage (broom sedge and wild legumes) for hogs and cattle, which grazed freely across the landscape.
Mountain farmstead subsistence farms dotted the mountain coves by 1900. Cattle and sheep ranged freely through the woods which were burnt each year to maintain forage.
1Cumberland NF 1934 McKee-Driprock Road E.S. Shipp
Photo #1: U.S. Forest Service Southern Research Station Collection, D.H. Ramsey Library, Special Collections, University of North Carolina at Asheville 28804
FARMING
Source: American Memory online photographic collection, Library of Congress
A mountain farm at Unicoi Gap in Georgia on the Blue Ridge Divide crest about 1930. Note the crown density on the skyline.
FARMING
Photo courtesy of R8 Digital Image Library at http://fsweb.r8.fs.fed.us/rf/pao/image_library/
Without fertilize ‘new grounds’ had to be cleared about every 5 to 7 years. But with only human and animal power available, the best technique was to girdle the trees in placeand plant underneath them.‘Grubbing’ with a ‘grubbinghoe’ removed hardwood rootstocks. Without cover crops winter erosion also depleted natural fertility.
U.S. Forest Service Southern Research Station Collection, D.H. Ramsey Library, Special Collections, University of North Carolina at Asheville 28804
The photo is of corn planted in 1922 on land burned in 1913. It is on the head of Harper Creek near Pineola, NC. The picture was taken by E.F. McCarthy.
FARMING
1880 AD until 1920 AD1880 AD until 1920 AD Near mountain communities, about 25% of Near mountain communities, about 25% of
the land was cultivated, 20% was cleared the land was cultivated, 20% was cleared pasture, and the remainder was forestpasture, and the remainder was forest
After the Civil War, the Industrial After the Civil War, the Industrial Revolution and the railroad made timber Revolution and the railroad made timber harvesting very profitable. Annual lumber harvesting very profitable. Annual lumber production in the South increased 1,000 production in the South increased 1,000 percent. In 1901, it was estimated that percent. In 1901, it was estimated that only 10% of the forest was still virgin only 10% of the forest was still virgin growth.growth.
A 1908 report estimated that 50% of A 1908 report estimated that 50% of Southern Appalachian timberland was Southern Appalachian timberland was owned by large companies, and 86% of the owned by large companies, and 86% of the acreage in the Southern mountains was acreage in the Southern mountains was either cleared, burned, or both.either cleared, burned, or both.
Steam skidders, railroads, and buying land outright set the stage for the ‘cut outand get out’ with much closer utilization.Note the smallest logs in these pictures.
CUT OUT & GET OUT
Earliest logging was near valley bottoms and concentrated on the best trees. Timber buyers bought individual trees for $0.50 to $1 on the stump and branded them for later cutting.
HIGH GRADING
1920 AD until Present1920 AD until Present Starting after passage of the Weeks Act in 1911, Starting after passage of the Weeks Act in 1911,
the Forest Service began to purchase land in the the Forest Service began to purchase land in the Southern Appalachians.Southern Appalachians.
Reforestation was not occurring on much of the Reforestation was not occurring on much of the land due to frequent large fires on cutover areas, land due to frequent large fires on cutover areas, so fire prevention became a primary task. In so fire prevention became a primary task. In southwestern Virginia, approximately 15 fires southwestern Virginia, approximately 15 fires burned a table mountain pine site from 1798 to burned a table mountain pine site from 1798 to 1935; since 1936, the study area has burned 1935; since 1936, the study area has burned only once. only once.
Proponents of open range were opposed to fire Proponents of open range were opposed to fire control, and arson was commonplace. New laws control, and arson was commonplace. New laws requiring fencing and ending open range requiring fencing and ending open range reduced the incentive for general burning.reduced the incentive for general burning.
Fires in heavy logging slash with fuel loadings ranging from 20 to over 50 tons/acre were intense and exposed mineral soil for the establishment of light-seeded, shade intolerant species. These fires werenot typical of the pre-historic or even early historic fire regime.
AFTERMATH
Source: USDA Forest Service Chattahoochee-Oconee NF file photo
Source: USDA Forest Service Chattahoochee-Oconee NF file photo
The combination of large-scale timber harvesting, chestnut blight,
and fire prevention has created a forest in the Southern Appalachians
probably unlike any forest that occurred in the past.
ConclusionsConclusions
It may not be possible to reproduce the chain It may not be possible to reproduce the chain of events that caused conditions in the pastof events that caused conditions in the past
Dense overstory shade often results in forests Dense overstory shade often results in forests with open understories, while sunlight on the with open understories, while sunlight on the ground can result in more dense growthground can result in more dense growth
Vegetation conditions can’t always be achieved Vegetation conditions can’t always be achieved by disturbing site at an average intervalby disturbing site at an average interval
ConclusionsConclusions
Past conditions might have developed due Past conditions might have developed due to irregular disturbances and intervalsto irregular disturbances and intervals
Exotic forest pest problems are Exotic forest pest problems are progressively affecting more native progressively affecting more native species, altering forest structure and species, altering forest structure and function. function.
ConclusionsConclusions
Vegetation effects vary according to the Vegetation effects vary according to the vegetation in place at the time of the vegetation in place at the time of the disturbancedisturbance
Management prescription should consider Management prescription should consider existingexisting species composition, stand species composition, stand structure, and site characteristicsstructure, and site characteristics
Use Use direct observationdirect observation along with academic along with academic conclusions based on indirect evidenceconclusions based on indirect evidence