Impact of Pine Conversion

Ecological Consequences of Hardwood Conversion to Pine Plantations on the Cumberland Plateau

Starting in the 1950’s and through to the 2000's, increased amounts of native forest were converted to loblolly pine plantations on the southern Cumberland Plateau. The Landscape Analysis Lab at the University of the South used aerial photography, satellite images, and on-the-ground assessment to measure changes in forest cover between 1981 to 2003 across a seven-county, 614,000-acre portion of the Cumberland Plateau in southern Tennessee. During this 22 year period, approximately 20% (95,000 acres) of the native forest was cleared or converted to other uses. The annual rate of forest conversion accelerated during this time period such that nearly as much forest was lost between 2000 and 2003 as was lost in the 16 years between 1981 and 1997. The highest rate of conversion to pine plantations occurred between 1997-2000 (Evans et al. 2002). Through a grant from the U.S. EPA and US Fish and Wildlife Service, we examined the ecological consequences of this land-use activity in the region.

Publications:

Haskell. D.G., J.P. Evans, and N. Pelkey. 2006. Depauperate avifauna in plantations compared to forests and residential areas. PLOS ONE 1: e63. doi:10.1371/journal.pone.0000063.

*Lemoine, D, J.P. Evans, and K. Smith. 2006. A landscape-level GIS analysis of streamside management zones on the Cumberland Plateau. Journal of Forestry 104:125-131.

McGrath, D., J.P. Evans, K. Smith, N. Pelkey, D. Haskell, R. Gottfried, C. Brocket, M. Lane, and E.D. Williams. 2004. Mapping land-use change and monitoring the impacts of hardwood-to-pine conversion on the southern Cumberland Plateau in Tennessee. Earth Interactions 8:1-24.

Evans, J.P. 2003. The southern pine bark beetle and forestry on the Cumberland Plateau in Tennessee: uniformity and vulnerability. Journal of the Forest Stewards Guild 16: 10-11.

Evans, J.P., N. Pelkey, and D. Haskell. 2002. An assessment of forest change on the Cumberland Plateau in Southern Tennessee: Small Area Forestry Demonstration Project for the Southern Forest Resource Assessment. Report on file with U.S. Environmental Protection Agency and the U.S. Fish and Wildlife Service. (Agency peer-reviewed).

Investigating Compliance with Sustainable Forestry Standards

The rate and magnitude of pine conversion and native forest loss varied across counties and watersheds within the study area. However, all counties showed a net loss of native forest, with Van Buren County being the highest. Pine conversion activity was highly clustered, causing a concentration of impact in certain counties and watersheds. The trends in clearing/conversion of intact native forests for pine conversion were observed mainly on land parcels owned by forestry industry corporations that claimed to be compliant/certified with forestry industry standards for sustainable forestry practices. From 1997 to 2000, 90% of all native forest removal resulted from clearings that were greater than 40 acres in size (Forest Stewardship Council certification limit) (Evans et al. 2002). Seventy percent of this native forest removal resulted from clearings that were greater than 120 acres in size (Sustainable Forestry Initiative certification average clearcut size limit). In study using GIS to assess streamside management zone compliance in areas impacted by pine conversion, we found very poor compliance with sustainable forestry certification standards for stream protection (Lemoine et al. 2006). Water quality in streams, as measured by the abundance of critical macroinvertebrates, was significantly lower in recently logged sites associated with pine conversion than in undisturbed native forest (Evans et al. 2002).

Tennessee Media Coverage:

Chattanooga Times Free Press May 30, 2006): “Study calls for better stream protection.”
Memphis Commercial Appeal (May 15, 2006): Guest Column: Logging bill chops into necessary protection.”
Chattanooga Times Free Press (July 19, 2005): “Spraying accord hailed.”
Chattanooga Times Free Press (July 13, 2005): “Bowater changes respond to market; environmentalists say company can, should do more.”
Chattanooga Times Free Press (July 13, 2005): “Neighbors welcome limits on aerial spraying.”
Chattanooga Times Free Press (July 3, 2005): Editorial: “A hopeful accord on forestry.”
Tennessean (June 30, 2005): “Southern forests, including the Cumberland Plateau, gain protection.”
Chattanooga Times Free Press (June 30, 2005 - front page story): “Bowater agrees to stop pine plantings.”
Crossville Chronicle (Mar. 4, 2005): “Protecting the Plateau’s Forests.”
Tennessean (Oct. 31, 2004): “Environmentalists working hard to protect the Cumberland Plateau.”
Tennessee Globe (Oct. 25, 2004). “Diverse Tennessee forest in danger.”
Nashville Scene (May 20-26): Editorial: “Hey Bredesen, it’s the land stupid.”
Chattanooga Times Free Press (Apr. 11, 2004): Invited Guest Editorial: “Trees in the balance - Commentary: State policies fail to address question of sustainability.”
Tennessean (Mar.21, 2004): Editorial: “Clear-cutting devastates environment, economy.”
Chattanooga Times Free Press (Mar. 15, 2004): “Fed, state at odds over spread of pine plantations.”
Chattanooga Times Free Press (Mar. 14, 2004 - front page story): “Finding a balance: timber is both a commodity and a natural resource.”
Tennessean (Mar 11, 2004); LTE: “It's not a secret - Plateau is endangered.”
Tennessean (Mar. 11, 2004): “Forest report skips plateau’s real plight, some activists say.”
Oneida Independent Herald (Mar. 8, 2004): “Plateau classified as “endangered.”
Tennessean (Feb. 28, 2004 - front page story): “Is the Cumberland Plateau among the most endangered.”
Sewanee Magazine (Spring 2003): “Fields of green.”
Chattanooga Times Free Press (Apr. 6, 2003): Editorial: “Threat to Cumberland Plateau.”
Chattanooga Times Free Press (Mar. 13, 2003): Editorial: “Flawed and costly forest policy.”
Chattanooga Times Free Press (Jan. 21, 2003 ): “Timber harvest could boost region’s economy.”
Chattanooga Times Free Press (Jan. 21, 2003 - front page story): “South’s changing landscape: pine plantations filling 13-state region to provide timber products.”
Chattanooga Times Free Press (Oct. 7, 2002): “EPA grant to fund Cumberland Plateau study.”
Knoxville News-Sentinel (May 28, 2002): “Harvest of pine changing nature, nurture of forest across South.”
Tennessean (May 26, 2002): “Demand, development put strain on Southern forests.”
Tennessean (April 22, 2002): “Native forests shrink quickly on Cumberland Plateau.”
Chattanooga Times Free Press (Mar. 30, 2002): “Study says plateau forests thinning.”
Franklin County Herald-Chronicle (Mar. 29, 2002): “New Sewanee study tracks forest changes”
Oak Ridger (Mar. 25, 2002): “Chipmill bill fails in legislative commitee.”
Grundy County Hearld (Mar. 21, 2002): “Sewanee study tracks declining plateau forests.”
WPLN, Nashville Public Radio (Mar. 14, 2002): Interview about SAA findings – loss of hardwoods on the Cumberland Plateau.
Franklin County NewsLeader (Mar.14, 2002): “Sewanee study tracks declining plateau forests.”
Chattanooga Times Free Press (Feb. 11, 2002): Times Editorial: “Threat to Cumberland Plateau.”
Chattanooga Times Free Press (Feb. 8, 2002– front page story): “Pine plantations overshadow forests.”
Chattanooga Times Free Press (Feb. 8, 2002): “New study provides tools for monitoring.”
Chattanooga Times Free Press (Dec. 5, 2001): “Study shows urbanization gobbling up forest land.”
Chattanooga Times Free Press (Nov. 16, 2001): “Environmentalists urge state water permit notification.”
Sewanee Magazine (Fall 2001): “This place: Sewanee’s dedication to environments near and far.”
Tullahoma Sunday News (July 29, 2001): “Sewanee forestry research study receives $90,000 grant from World Wildlife Fund.”
Chattanooga Times Free Press (May 3, 2001): “Chip mill regulation bill delayed.”
Chattanooga Times Free Press (April 11, 2001): Times Editorial: “Prayers for sane forestry bills.”
Chattanooga CityScope Magazine (Fall 2000): “Chip mills become a growing concern.”
Tennessean (Sept. 22, 2000): “Condition of state’s forests debated: Data lends itself to opposing sides.”
Knoxville News-Sentinel (Aug. 8, 2000): “Forest issues spark comment.”
Chattanooga Times Free Press (August 14, 2000): “Forests in South getting attention.”
Chattanooga Times Free Press (July 14, 2000): “Tennessee timber being replaced faster than it’s cut, Survey says.”
Knoxville News-Sentinel (July 13, 2000 – front page story): “Some concerned by trend to clear hardwoods, plant pine plantations.”
Tennessean (March 16, 2000): “Aerial view of cut trees opens eyes of senator.”
Chattanooga Times Free Press (Feb. 14, 2000): “Aerial service monitoring area forests.”

Projects

Southern Pine Bark Beetle Epidemic

Between 1998 and 2002, vast acreages of loblolly pine plantations on the Plateau were decimated by southern pine bark beetle (Dendroctonus frontalis) whose epidemic-level infestations occurred at unprecedented proportions (Evans 2003). Pine stands located on state recreation lands and owned by small landowners were also severely affected. The economic loss associated with this recent southern pine bark beetle (SPB) epidemic on the Plateau in TN has been estimated at over 100 million dollars, in a region already considered to be one of the most economically depressed in the nation. The drought-prone, upland environment of the Cumberland Plateau is outside the native range of loblolly pine, a species adapted to bottomland, coastal plain environments. Heavily stocked stands of loblolly pine (such as those intended for pulping) and loblolly stands that are stressed by limited water availability have been shown to be particularly susceptible to epidemic-level SPB infestations in which immature and healthy trees are killed. The presence of these large continuous monocultures of pine greatly enhance the dispersability and outbreak intensity of SBP across the landscape. Ecological models predict that the SPB range will expand northward in the coming decades and become more established in areas such as the Cumberland Plateau (which is currently on the edge of its range) as major epidemics in plantations become less inhibited by low winter temperatures. We suggest that epidemic-level outbreaks of SPB are not going to go away in landscapes such as the Cumberland Plateau that are becoming increasingly dominated by pine plantation activity, putting into question the future sustainability of this enterprise (Evans 2003).

Loss of Forest Soil Productivity

In a study comparing the effects of whole-tree harvesting on the cation budgets of several forests throughout the United States, the Cumberland Plateau was one of the few sites studied where cation export from whole-tree removal greatly exceeded loss due to leaching. This was partly attributable to the large amount of stored calcium in the dominant plateau tree species. The Landscape Lab examined the biogeochemistry of hardwood conversion to pine plantations on the Plateau and found that a considerable loss of calcium and other nutrients from the system occurred by the second rotation of pine (McGrath et al 2004). The research suggested that this nutrient depletion process can seriously impact the productivity of future rotations of pine as well as potentially alter the species composition and reduce the long-term health of any native forest that is restored to lands previously dominated by pine plantations.

Impacts on Bird Communities

We found that forest conversion resulted in significant impacts on the diversity of bird communities on the Plateau (Haskell et al. 2006). Pine plantations were shown to have the lowest bird diversity and had the lowest conservation value, as measured by independently-derived Partners in Flight (PIF) priority scores. The intact native forests had the next highest diversity and PIF conservation value. Native forests on the Plateau had some of the highest levels of bird diversity found anywhere in the forests of the south-eastern U.S., indicating that this region offers high quality habitat for forest-dwelling birds. Neither pine plantations nor residential areas can support the bird communities found in the native forests of the Cumberland Plateau. However, residential areas do provide habitat for several species that are found in no other habitat types on the Plateau. In addition, residential areas, young pine plantations, and thinned native forests all provide habitat for a few specialist bird species that require a more open or grassy habitat. Some of these specialists are also present in patches of natural disturbance in native forests. Our research suggested that the species-rich bird communities of the Cumberland Plateau are more vulnerable to loss of bird diversity when subjected to intensive timber management than are bird communities with relatively low species richness in other regions such as boreal and sub-boreal forests.

Consequences of Clearcutting

We found that on the Plateau, the primary use of clearcutting was for forest removal, not the regeneration of hardwoods (Evans et al. 2002). Clearcutting was the first step in the conversion process from hardwood to pine plantation, agriculture or residential development. Clearcutting for hardwood regeneration increased the likelihood of future conversion to other land uses. Only 50% of land that was clearcut for this purpose in 1981 was still in hardwood by 2000. Forest conversion on the Plateau is currently unidirectional process. Between 1980 and 2003 less than 2% of the land in pine plantation, agriculture of residential had been allowed to revert back to native hardwood.

New York Times (Aug. 8, 2000 – front page story): “Logging’s shift South brings concern on oversight"

Chattanooga Times Free Press (July 14, 2000): “Tennessee timber being replaced faster than it’s cut, Survey says.”

Knoxville News-Sentinel (July 13, 2000 – front page story): “Some concerned by trend to clear hardwoods, plant pine plantations.”

Washington Post (June 3, 2000 – front page story): “Chipping away at the South’s forests.”

Suite101.com (May 12, 2000): “The case against pine plantations.”

Newshour with Jim Leher (May 1, 2000): “Forest fight.”

Mother Jones Magazine (May/June 2000): “False forests.”

Sports Afield Magazine (March 2000 Issue): “The browning of the southland.”

CNN Earth Matters (Dec. 19, 1999): “Chipping Dixie.”

CNN Headline News (Dec. 18, 1999): “Chipping Dixie.”

Wall Street Journal (Sept. 27, 1999 – front page story): “Forget spotted owls, clear-cutting in the South is the latest forestry flap.”

National Media Coverage:

New Orleans Times-Picayune (Oct. 8, 2013): Tennessee’s fragile Cumberland Plateau ecosystem threatened by human interaction, scientists say.

ACS Green Times (Aug 2010) Mighty oaks from tiny acorns: Sewanee’s Landscape Analysis Lab and Environmental Institute

UPI (June 6, 2006): “Timber harvesters ignore streamside areas.”

LAL Plateau Case Study included in: Making Maps : A Visual Guide to Map Design for GIS (2006) by John Krygier, Denis Wood.

Appalachian Voice (Early Winter 2005): Conservationists, industry reach historic agreement to protect forests on the Cumberland Plateau.

Daily Grist (Oct. 25, 2004): “Tennessee faults: conservationists use market to save Cumberland Plateau hardwood.”

Greenwire (Oct. 25, 2004). Forests: enviros take on Cumberland Plateau logging practices.

Detroit News (Oct. 24, 2004). “Diverse Tennessee forest in danger.”

Washington Post (Oct. 24, 2004). Conservation's company plan -- firms are asked to examine paper use in effort to save forest.

E Magazine (May/June 2004): "Plantation pines: the paper industry moves South"

Onearth Magazine - NRDC (Winter 2004 - Cover Story): “The Tennessee chainsaw massacre.”

Orlando Sentinel (June 2, 2002): “Forests in flux.”

MSNBC (May 31, 2002): “Southern U.S. rooted in private forests: Tree growing becomes area’s largest resource.”

St. Louis Post-Dispatch (May 30, 2002): “Private ownership rules in the South’s timberlands.”

Winston-Salem Journal (May 28, 2002): “Remaking nature: With tree farms privately owned and development growing, Southern forests are losing hardwoods, longleaf pines.”

Savannah Morning News (May 25, 2002): “Plantation culture: Pine farms redraw the Southern landscape.”

AP News (May 25, 2002): “Plantation culture: Pine farms redraw the Southern landscape.”

Tampa Tribune (May 24, 2002): “Face of the forests: Private owners stewards of South's biggest resource.”

AP News (May 24, 2002): “Face of the forests: Private owners stewards of South's biggest resource.”

Los Angeles Times (May 23, 2002 – front page story): “Mistaking trees for a forest?; Southern timber harvest replaces native hardwoods with rows of pines.”

Atlanta Journal-Constitution (Nov. 27, 2001): “Vast loss of forests forecast”

New York Times (Nov. 27, 2001): “Sprawl seen hurting South’s forests.”

WILDlines (April 16, 2001): “Hardwood protection a hard sell in Tennessee.”

Forest Conservation

Plant Ecology & Conservation Lab

Jon Evans, Ph.D.

Sewanee Herbarium

Ecological Consequences of Hardwood Conversion to Pine Plantations on the Cumberland Plateau