Restoring Ecological Health of Restoring Ecological Health of America’s ForestsAmerica’s Forests

Wally CovingtonWally Covington

Regents’ Professor, School of ForestryRegents’ Professor, School of Forestryand Executive Director,and Executive Director,

Ecological Restoration InstituteEcological Restoration InstituteNorthern Arizona UniversityNorthern Arizona University

The Least You Need to KnowThe Least You Need to Know

America’s forests are out of whackAmerica’s forests are out of whack Frequent fire forests, in particular, have Frequent fire forests, in particular, have

unnaturally high tree densities and fuel loadsunnaturally high tree densities and fuel loads Under these conditions, fire intensity and size Under these conditions, fire intensity and size

have been steadily increasinghave been steadily increasing Research shows that restoration can solve Research shows that restoration can solve

forest health problems and provide economic forest health problems and provide economic benefitsbenefits

We must increase the scale and pace of We must increase the scale and pace of treatmentstreatments

What Do We Mean by the What Do We Mean by the Term Frequent Fire Forests?Term Frequent Fire Forests?

Forests which over evolutionary time have Forests which over evolutionary time have become adapted to frequent, low intensity become adapted to frequent, low intensity surface firesurface fire

Examples include longleaf pine, red pine, Examples include longleaf pine, red pine, ponderosa pine, Jeffrey pine, and a wide ponderosa pine, Jeffrey pine, and a wide range of dry oak-hickory forestsrange of dry oak-hickory forests

Under natural conditions, these frequent Under natural conditions, these frequent fires kept tree populations in check, fires kept tree populations in check, recycled nutrients, and prevented fuel recycled nutrients, and prevented fuel accumulationaccumulation

Unnaturally High Tree Densities and Unnaturally High Tree Densities and

Climate Change are a Recipe for Climate Change are a Recipe for Disaster Disaster Tree densities in many forest types in Tree densities in many forest types in

the U.S. exceed the carrying capacity of the U.S. exceed the carrying capacity of the land, especially in frequent fire the land, especially in frequent fire forest typesforest types

Excessive tree densities (20 to 100 Excessive tree densities (20 to 100 times natural densities) make forests times natural densities) make forests weak and vulnerable to unnatural insect weak and vulnerable to unnatural insect and disease outbreaks and increasingly and disease outbreaks and increasingly large and devastating crown fireslarge and devastating crown fires

How Did Forests Become How Did Forests Become Excessively Dense and at Excessively Dense and at

Risk?Risk? Overgrazing eliminated natural Overgrazing eliminated natural

surface firessurface fires Fire suppression allowed tree Fire suppression allowed tree

establishment far beyond the establishment far beyond the carrying capacity of the landcarrying capacity of the land

We failed to adequately control We failed to adequately control tree density and fuel loadingtree density and fuel loading

Increased Tree Density and Timber Increased Tree Density and Timber Volume Have Come at Costs to Other Volume Have Come at Costs to Other

Resources Resources decreased stream flowdecreased stream flow decreased groundwater rechargedecreased groundwater recharge decreased herbaceous productiondecreased herbaceous production decreased wildlife habitatdecreased wildlife habitat decreased biological diversitydecreased biological diversity increased fuel loading and crown fire riskincreased fuel loading and crown fire risk increased susceptibility to unnatural increased susceptibility to unnatural

insect and disease outbreaksinsect and disease outbreaks

Principles for Developing Principles for Developing Restoration PrescriptionsRestoration Prescriptions

Protect old trees which are rareProtect old trees which are rare Retain post-settlement trees needed Retain post-settlement trees needed

to re-establish sustainable forest to re-establish sustainable forest structurestructure

Thin and remove excess trees; Thin and remove excess trees; where feasible, provide wood for where feasible, provide wood for economic useseconomic uses

Burn at more or less natural Burn at more or less natural intervals to hold tree densities and intervals to hold tree densities and fuel loads in checkfuel loads in check

We must act a scale and pace in keeping with the character of the crises We must act a scale and pace in keeping with the character of the crises at hand. Large, collaborative landscape scale projects are our best hope. at hand. Large, collaborative landscape scale projects are our best hope.

The catastrophic “mega-fires” The catastrophic “mega-fires” of 2000, 2002, and 2011, and of 2000, 2002, and 2011, and the bark beetle outbreaks of the bark beetle outbreaks of 2000, 2007, and 2010 were 2000, 2007, and 2010 were predictedpredicted

The trend will continue until The trend will continue until we intervene, and intervene we intervene, and intervene in a big way.in a big way.

Tree densities must be Tree densities must be reduced to levels consistent reduced to levels consistent with natural with natural conditionsconditions

Comprehensive ecological Comprehensive ecological restoration is prudent. restoration is prudent. It not only reduces crown fire It not only reduces crown fire threat, but converts forest threat, but converts forest which have become a liability which have become a liability into an asset for present and into an asset for present and future generations. future generations.

Scientific and technical Scientific and technical support for restoring the support for restoring the ecological and economic ecological and economic

health of forested health of forested landscapeslandscapes

eri.nau.edueri.nau.eduDiane Vosick, Director Diane Vosick, Director

of Policy and of Policy and PartnershipsPartnerships