Table 1.―Annual estimates, uncertainty, and change.

Figure 1.―Area of forest land and timberland by year.

Figure 2.―Area of forest land by size class and top six 

forest types.

Pennsylvania’s Forest Resources, 2011 Research Note NRS-157

This publication provides an overview of forest resource attributes for Pennsylvania based on an annual inventory 

conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest 

Service. These annual estimates, along with web-posted core tables, will be updated annually. For more information 

please refer to page 4 of this report.

1

Note: When available, sampling errors and bars provided in the 

figures and tables represent a 68 percent confidence interval. 

Figure 3.―Area of timberland by stand size class and 

year.

Estimate 

(2011)

Sampling 

error (%)

Change(%) 

since 2006

Forest Land Estimates

Area (1,000 acres) 16,782 0.7 1.1

Number of live trees > 1-inch 

diameter (million trees) 8,166 1.7 -3.2

Dry biomass of live trees > 1-inch 

diameter (1,000 tons) 1,044,899 1.0 4.9

Net volume of live trees > 5-inch 

diameter (million ft3

) 36,587 1.1 5.3

Annual net growth of live trees > 

5-inch diameter (1,000 ft3

/year) 872,877 3.0 2.1

Annual mortality of live trees 

(1,000 ft3

/year) 335,341 4.1 11.5

Annual harvest removals of live 

trees (1,000 ft3

/year) 398,856 7.2 -1.6

Annual other removals of live 

trees (1,000 ft3

/year) 11,565 28.7 -66.9

Timberland Estimates

Area (1,000 acres) 16,241 0.8 1.0

Number of growing-stock trees > 

5-inch diameter (million trees) 7,955 1.7 -3.5

Dry Biomass of live trees > 

1-inch diameter (1,000 tons) 1,009,147 1.1 4.6

Net volume of live trees > 5-inch 

diameter (million ft3

) 35,320 1.2 4.9

Net volume of growing-stock trees 

(million ft3

) 32,431 1.2 2.0

Annual net growth of growingstock trees (1,000 ft3

/year) 752,639 3.1 -2.0

Annual mortality of growing-stock 

trees (1,000 ft3

/year) 247,629 4.6 14.7

Annual harvest removals of 

growing-stock trees(1,000 

3

340,253 7.2 0.2

Annual other removals of growingstock trees (1,000 ft3

/year) 37,230 27.2 -52.3
Table 2.―Top 10 species by statewide volume estimates 2011.

2

Figure. 4.―Area of forest land (acres) by major owner group, 2011.

1 Red maple 6,696.8 2.6 3.3 16,331.4 3.8 10.4

2 Black cherry 3,980.0 4.0 10.2 12,615.0 5.3 13.2

3 Northern red oak 3,550.7 3.9 6.2 14,085.7 4.5 10.4

4 Sugar maple 2,660.8 4.8 6.7 7,935.7 6.0 14.5

5 Chestnut oak 2,539.5 4.3 -1.7 6,852.0 5.2 2.9

6 Eastern hemlock 1,845.6 5.8 4.7 5,302.9 6.7 6.4

7 White ash 1,727.7 5.1 4.9 5,237.2 6.8 3.0

8 Yellow-poplar 1,709.2 7.8 11.6 7,400.4 8.7 18.7

9 White oak 1,625.8 5.3 2.2 5,426.9 6.6 5.9

10 Sweet birch 1,541.5 4.6 7.7 2,880.3 6.6 10.2

Other hardwoods 1,648.5 6.6 6.5 5,297.5 7.6 9.3

Other softwoods 7,060.7 2.3 4.9 19,324.2 3.3 10.7

All species 36,586.8 1.1 5.3 108,689.0 1.6 10.2

Change 

(%) 

since 

2006

Volume of live 

trees on forest 

land (million 

ft3)

Change 

(%) 

since 

2006 

Volume of 

sawtimber trees on 

timberland (million 

bdft)

Rank Sampling 

error 

(%)

Sampling 

error 

(%)

Species

510,727

137,086

3,806,553

538,254

11,799,340

National Forest

Other federal

State

Local and Municipal

Private
3

Chestnut Oak Dynamics

Chestnut oak (Quercus prinus) is the second most prominent oak in Pennsylvania containing 2.54 

billion cubic feet. The species grows on mesic rolling uplands and on drier slopes and ridges. It can 

out-compete the other oaks on the more xeric ridge tops (Collins and Carson 2004). The species is 

commonly found with scarlet oak and black oak on the drier rockier ridge tops; and with red oak, 

white oak, and pignut hickory on the more mesic sites (Iverson et al. 2008). The species stocking is 

primarily concentrated in the chestnut oak, and the chestnut oak-black oak-scarlet oak, forest types. 

Lower concentrations are found in the white oak-red oak-hickory, white oak, and the yellow-popularwhite oak-northern red oak, forest types. 

In comparison to the other associate oak species, chestnut oak has a higher level of mortality while 

being exposed to many of the same stressors (Table 3).

Table 3. Chestnut verses other oaks in volume, net growth, and mortality (cubic feet) for all 

live trees >5 inches diameter at breast height (d.b.h.) in Pennsylvania, 2011.

One of the common stressors to the oaks is the gypsy moth (Lymantria dispar L.), an introduced 

defoliator of oak forests. Gypsy moths has the ability to change the stand composition away from oak 

dominance (Rieske 2002). During the 2005-2009 period, gypsy moth defoliation coupled with drought 

and attacks by two secondary pests, two-lined chestnut borer and Armillaria root rot, had major 

impacts. Research needs to be conducted to determine if this insect prefers chestnut oak over the 

other oak species; or is this mortality due to a combination of stressors including forces of 

succession? 

There are treatments which benefit oaks while inhibiting gypsy moth. Prescribed fire can be an 

effective tool at reducing the insect’s effects while improving oak regeneration. Midstory thinnings can 

also improve stand regeneration on less rocky sites (Iverson et al. 2008). 

Attribute Northern red oak Chestnut oak White oak Black oak Scarlet oak

Volume (ft3) 3,550,735,661 2,539,497,258 1,625,832,328 951,565,112 457,881,672

Net growth (ft3) 98,601,843 29,507,390 33,981,833 27,635,606 12,692,290

Mortality(ft3) 22,119,154 29,976,492 11,835,018 6,682,783 5,631,641

Net growth / volume (%) 2.8 1.2 2.1 2.9 2.8

Mortality / volume (%) 0.6 1.2 0.7 0.7 1.2

Mortality / Net growth (%) 22.4 101.6 34.8 24.2 44.4
Bechtold, W.A.; Patterson, P.L. 2005. The enhanced Forest Inventory and Analysis Program: national sampling 

design and estimation procedures. Gen. Tech. Rep. SRS-80. Asheville, NC: U.S. Department of Agriculture, Forest 

Service, Southern Research Station. 85 p.

Marquis, David A., ed. 1994. Quantitative silviculture for hardwood forests of the Alleghenies. Gen. Tech. Rep. NE183. Radnor, PA: U.S. Department of Agriculture Forest Service, Northeastern Forest Experiment Station. 143 p.

Smith, W.B. 2002. Forest inventory and analysis: a national inventory and monitoring program. Environmental 

Pollution. 116: 233-242.

USDA Forest Service. 2009. Forest inventory and analysis national core field guide, Vol. 1, field data collection 

procedures for Phase 2 plots, Ver. 5.0. Available at www.fia.fs.fed.us/library/field-guides-methods-proc(verified July 

2009). 

FIA Program Information

McCaskill, G.L.; McWilliams, W.H.; Barnett, C.J. 2012. Pennsylvania’s forest resources, 2011. Res. Note. NRS-157. 

Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. 4 p.

Citation for this Publication

4

Additional Pennsylvania Inventory Information

Alerich, Carol A. 1993. Forest statistics for Pennsylvania--1978 and 1989. Res. Bull. NE-126. Radnor, PA: U.S. 

Department of Agriculture, Forest Service, Northeastern Forest Experiment Station. 244 p.

Widmann, Richard H. 1995. Forest Resources of Pennsylvania. Res. Bull. NE-131. Radnor, PA: U.S. Department of 

Agriculture, Forest Service, Northeastern Forest Experiment Station. 41 p.

McWilliams, William H.; Cassell, Seth P.; Alerich, Carol L.; Butler, Brett J.; Hoppus, Michael L.; et al. 2007. 

Pennsylvania’s Forest, 2004. Resour. Bull. NRS-20. Newtown Square, PA: U.S. Department of 

Agriculture, Forest Service, Northern Research Station. 86 p.

The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national 

origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic 

information, political beliefs, reprisal, or because all or part of an individual’s income is derived from any public assistance program (Not all 

prohibited bases apply to all programs.) Persons with disabilities who require alternate means for communication of program information 

(Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of 

discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, DC 20250-9410, or call 

(800)795-3272 (voice) or (202)720-6382 (TDD). USDA is an equal opportunity provider and employer.

Contact Information Pennsylvania Analyst: George L. McCaskill 610-557-4045 georgemccaskill@fs.fed.us

Data Acquisition / web sites: Charles J. Barnett, 610-557-4031, cjbarnett@fs.fed.us

Website: fiatools.fs.fed.us

Additional Information

Collins, R.J.; Carson, W.P. 2004. The effects of environment and life stage on Quercus abundance in the 

eastern deciduous forest, USA: are sapling densities most responsive to environmental gradients? Forest 

Ecology and Management. 201:241-258.

Iverson, L.R.; Hutchinson, T.F.; Prasad, A.M.; Peters, M.P. 2008. Thinning, fire, and oak regeneration across a 

heterogeneous landscape in the eastern U.S.: 7-Year results. Forest Ecology and Management. 255: 3035-3050. 

Rieske, L.K. 2002. Wildfire alters oak growth, foliar chemistry, and herbivory. Forest Ecology and Management. 

168: 91-99.