New Hampshire Forests 

2017

United States Department of Agriculture

Forest Service Northern 

Research Station

Resource Bulletin

NRS-119

Publication Date

January 2020
Abstract

The second full remeasurement of the annual inventory of the forests of New Hampshire was 

completed in 2017 and covers more than 4.7 million acres of forest land, with an average volume of 

over 2,300 cubic feet per acre. The data in this report are based on 1,162 plots located across New 

Hampshire. Forest land is dominated by the maple/beech/birch forest-type group, which occupies 

52 percent of total forest land area. Of the forest land, 64 percent consists of large diameter trees, 25 

percent contains medium diameter trees, and 11 percent contains small diameter trees. The volume 

of growing stock on timberland has continued to increase since the 1980s and currently totals nearly 

9.5 billion cubic feet. The average annual net growth of growing stock on timberland from 2012 to 

2017 was over 180 million cubic feet per year. Additional information is presented on forest attributes, 

land use change, carbon, species composition, regeneration, and forest health. Sets of supplemental 

tables are available online at https://doi.org/10.2737/NRS-RB-119 and contain: 1) tables that 

summarize quality assurance and 2) a core set of estimates for a variety of forest resources.

Acknowledgments

The authors would like to thank inventory crew members from New Hampshire for their help during 

the 2008–2017 inventory years: Aaron Clark, Robert Gregory, John Higham, Katherine Locke, Jason 

Morrison, Joyce Quinn, Bryan Tirrell, and Ashley Zickefoose. Thanks also to Susan Francher and 

Paul Frederick for serving as external reviewers and providing insightful, constructive comments.

Manuscript received for publication July 2019

Published by

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January 2020

For additional copies:

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Cover: View of the Presidential Range of the White Mountains. Photo by Randall Morin, USDA Forest 

Service.

Visit our homepage at: https://www.nrs.fs.fed.us

Printed on recycled paper
Hew Hampshire Forests 2017

Randall S. Morin, Brett J. Butler, Susan J. Crocker, Jonathan Horton, Cassandra M. Kurtz, 

Tonya W. Lister, William H. McWilliams, Mark D. Nelson, Rachel Riemann, Brian F. Walters, 

and Christopher W. Woodall

Contact Author:

Randall S. Morin

randall.s.morin@usda.gov

610-557-4054

About the Authors

Randall S. Morin, Tonya W. Lister, and William 

H. McWilliams are research foresters with the 

Forest Inventory and Analysis (FIA) program, 

Northern Research Station, Newtown Square, PA.

Brett J. Butler is a research forester with the 

FIA program, Northern Research Station, 

Amherst, MA.

Susan J. Crocker and Mark D. Nelson are 

research foresters with the FIA program, 

Northern Research Station, St. Paul, MN.

Jonathan Horton is a forest resource analyst 

with the New Hampshire Division of Forests and 

Lands, Concord, NH.

Cassandra M. Kurtz and Brian F. Walters are 

foresters with the FIA program, Northern 

Research Station, St. Paul, MN.

Rachel Riemann is a research forester with 

the FIA program, Northern Research Station, 

Troy, NY.

Christopher W. Woodall is a research forester 

with the Northern Research Station, 

Durham, NH.
Foreword

The landscape of New Hampshire has undergone many changes during its history. 

One of the constants has been a working forest landscape that provides goods and 

services through stewardship, management, and conservation. We depend upon the 

forest for timber, maple syrup, and firewood, along with values and services such 

as watershed protection, wildlife habitats, carbon sequestration, outdoor recreation 

opportunities, and scenic beauty. Forests dominate the landscape of New Hampshire; 

decisions we make and actions we take today to care for those lands need to be 

informed by accurate and timely data.

The New Hampshire Division of Forests and Lands is pleased to be a partner of 

the U.S. Forest Service in the Forest Inventory and Analysis (FIA) inventory of 

New Hampshire forests. The more we know and understand the resources of our 

forests, the better we can sustain our forests. Sustainable forests begin with healthy 

forests, and we encourage you to become familiar with information contained in this 

publication.

Brad W. Simpkins

New Hampshire State Forester
Contents

Highlights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Forest Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Ecosystem Indicators and Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Literature Cited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

New Hampshire Forests Summary Tables

 Online at https://doi.org/10.2737/NRS-RB-119

Additional Resources

 Online at https://doi.org/10.2737/NRS-RB-119
Wooded stream in Franconia State Park. Photo by Elizabeth Morin, used with permission.
 | 1

Highlights

On the Plus Side

• New Hampshire is the second most forested state in the United States.

• Participation in New Hampshire’s current use taxation has increased, which may 

reduce the amount of forest land converted to other uses.

• Changes in stand stocking toward more moderately and fully stocked stands suggest 

that forest management practices over the past three decades have improved the 

general stocking condition across New Hampshire.

• Most forest carbon in New Hampshire is found in moderate-aged stands dominated 

by relatively long-lived species, suggesting that forest carbon stocks will continue to 

increase as stands mature and accumulate carbon in aboveground and belowground 

components.

• Timber resources in New Hampshire are at near-record levels since inventories 

began in 1948. 

• The mortality rate (0.7 percent) for the 2017 inventory is slightly lower than what 

was reported for the 2012 and 2007 inventories.

• Tree crowns are generally healthy and stable across the State.

• The ratio of growth to removals of 1.9:1.0 in New Hampshire indicates that 

growth is adding nearly twice as much volume annually as is getting removed by 

harvesting.

Areas of Concern

• Commercial and residential development of forest land, particularly in the southern 

quarter of the State, has resulted in reductions in forest land use. New Hampshire 

lost forest land at a rate of about 0.4 percent per year between 2012 and 2017.

• The expected transfer of 1.6 million acres of family forest land foreshadowed by the 

advanced age (65+) of many owners is an important trend to monitor as the fate of 

forests is most likely to change when forest land is passed to the next generation of 

owners.

• The total volume of sawtimber in New Hampshire has decreased slightly since 2012, 

mostly due to the decrease in forest land.
2 | 

• Timber volume peaked in 2012 and the rate of growth has leveled off as the forest 

matures, a trend that is likely to continue into the future.

• The dominance of beech and noncommercial tree species in the sapling size class 

raises concerns about the future species composition in New Hampshire.

• The proportion of ash basal area with poor crowns has more than doubled since 

2012, but the relative amount is still low (6 percent).

• The presence of nonnative invasive plant species has remained stable since the 2012 

inventory.

Issues to Watch

• The small parcels held by many landowners and the trend toward more landowners 

with smaller parcels complicate the economics of forest management and the 

delivery of government programs.

• The trend toward more area of large diameter and less area of small and medium 

diameter trees in New Hampshire needs continued monitoring.

• Although wood volume continues to accumulate as the forests mature, only a small 

fraction of the accumulated material is available for use as wood products.

• The total volume of timber resources in New Hampshire has started to decrease 

for the first time since the Forest Service’s Forest Inventory and Analysis program 

began doing inventories in the State in 1948. The slight decrease in timberland area 

along with a slowing rate of increase in growing-stock volumes has resulted in this 

reduction in total timber volume. Growth rates may decrease further as the forest 

ages.

• If the current species composition remains constant as saplings mature, the future 

forest overstory will have more red maple and balsam fir trees and less eastern white 

pine, eastern hemlock, and northern red oak than today.

• Although the proportion of high grade volume has remained relatively stable, 

changes in species composition point toward potential reductions in overall 

sawtimber quality into the future.

• An important consideration for those landowners actively managing their land is 

the ability of the primary wood products industry to retain pulp mills, sawmills, 

and veneer mills within a distance that allows for a sustainable market for the 

harvested material.
 | 3

• Invasive insect pests that are likely to impact abundant tree species in New 

Hampshire in the future include hemlock woolly adelgid, emerald ash borer, and 

Asian longhorned beetle.

• The risk of catastrophic economic and ecological loss of forest resources could 

increase due to forest maturity and more extreme weather-related events, including 

hurricanes, droughts, and floods caused by a changing climatic regime. 

• Two highly valuable commercial species, eastern white pine and red oak, are nearly 

absent in the smaller size classes in New Hampshire. 

• A maturing forest structure continues to limit pioneer and other shade-intolerant 

species that thrive in sunnier forested conditions.

• Frequent tree damage (25 percent of trees) and internal decay on 11 percent of trees 

in New Hampshire may be an indication of reduced tree health and timber quality.

• Urbanization is affecting an increasing amount of forest area in New Hampshire. 

A total of 1.3 million acres (28 percent of New Hampshire forest land) was in 

wildland-urban interface (WUI) conditions by 1990, and between 1990 and 2010 

forest land was converted to WUI conditions in the majority of counties at rates 

greater than 5 percentage points per decade.

Overlooking the Pine Creek Valley in Lycoming County. Photo by Thomas Albright, U.S. Forest Service.
Page intentionally left blank
Background

| 5

View of the Presidential Range of the White Mountains. Photo by Randall Morin, USDA Forest Service.
6 | BACKGROUND

Data Sources and Techniques

The forests of New Hampshire are one of northern New England’s most valuable 

assets due to their importance to the economy and quality of life for residents. 

Accurate and statistically defensible information is critical for understanding the 

current conditions, interpreting trends over time, and projecting future scenarios. 

This report highlights the current status and trends observed in the forests of 

New Hampshire and is the culmination of the second complete remeasurement 

of the inventory using the USDA Forest Service Forest Inventory and Analysis 

(FIA) program’s annualized forest inventory system. Data are based on 1,162 plots 

located across New Hampshire. Previous forest inventories in New Hampshire were 

completed in 1952 (USDA Forest Service 1954), 1960 (Ferguson and Jensen 1963), 

1973 (Frieswyk and Malley 1985, Kingsley 1976), 1983 (Frieswyk and Malley 1985, 

Frieswyk and Widmann 2000), 1997 (Frieswyk and Widmann 2000), 2007 (Morin et 

al. 2011), and 2012 (Morin et al. 2015a). The annualized system was implemented in 

New Hampshire in 2002 to provide updated forest inventory information every year. 

The FIA program is the only source of data collected from a permanent network of 

ground plots from across the Nation that allows for comparisons to be made among 

states and regions. The most recent inventory period was conducted from 2011 

through 2017 and hereafter is referred to as the 2017 inventory.

The FIA sampling design is based on a tessellation of the United States into hexagons 

approximately 6,000 acres in size with at least one permanent plot established in 

each hexagon. In Phase 1 (P1), the population of interest is stratified and plots are 

assigned to strata to increase the precision of estimates. In Phase 2 (P2), tree and site 

attributes are measured for forested plots established in each hexagon. Phase 2 plots 

consist of four 24-foot fixed-radius subplots on which standing trees are inventoried. 

This sampling design results in 1,162 long-term inventory plots in New Hampshire. 

In Phase 3 (P3), field crews visited a subset of P2 plots to obtain measurements for an 

additional suite of variables associated with forest and ecosystem health. P3 has been 

replaced by Phase 2+ (P2+), in which fewer data are collected per plot but more plots 

are sampled. Otherwise, P2+ follows the same paradigm as the retired P3, focusing 

on forest and ecosystem health. Detailed information on the sampling protocols can 

be found in the report on statistics and quality assurance (Gormanson et al. 2018). A 

glossary of terms commonly used in FIA reports is available at https://www.nrs.fs.fed.

us/fia/data-tools/state-reports/glossary. Supplemental tables summarizing the results 

reported for New Hampshire are available at https://doi.org/10.2737/NRS-RB-119.
BACKGROUND | 7

An Overview of Forest Inventory

What is a tree? 

Trees are perennial woody plants with central stems and distinct crowns. FIA 

defines a tree as any perennial woody plant species that can attain a height of 15 

feet at maturity. A list of the tree species mentioned in this report is included in the 

appendix. Throughout this report, the size of a tree is usually expressed as diameter 

at breast height (d.b.h.), in inches. This is the diameter, outside the bark, at a point 4.5 

feet above the ground.

What is a forest?

A forest is a collection of trees and most people would agree on what a forest is. But 

in order for statistics to be reliable and comparable, a definition must be created to 

avoid ambiguity. FIA defines forest land as land that has at least 10-percent tree cover 

and is not currently developed for nonforest use. Generally, the minimum area for 

classification as a forest is 1 acre in size and 120 feet in width. There are more specific 

criteria for defining forest land near streams, rights-of-way, and shelterbelt strips 

(USDA Forest Service 2016).

What is the difference between timberland, reserved forest 

land, and other forest land?

From an FIA perspective, there are three types of forest land: timberland, reserved 

forest land, and other forest land. In New Hampshire, approximately 94 percent of 

all forest land is classified as unreserved and productive timberland and 6 percent is 

reserved or unproductive (or both) forest land.

• Timberland is unreserved forest land that meets the minimum productivity 

requirement of 20 cubic feet per acre per year.

• Reserved forest land is land withdrawn from timber utilization through legislative 

regulation without regard to productive status (e.g., state parks, natural areas, 

national parks, and Federal wilderness areas). All reserved forest land is in public 

ownerships.

• Other forest land is commonly found on low-lying sites or high craggy areas with 

poor soils where the forest is incapable of producing at least 20 cubic feet per acre 

per year. In earlier inventories, FIA measured trees only on timberland plots and 

did not report volumes on all forest land. Since the implementation of the annual 

inventory, FIA has been reporting volume on all forest land. 
8 | BACKGROUND

• With the second remeasurement completed, comparison of three sets of growth, 

mortality, and removals data, as well as analysis of trends on forest land, is now 

possible. However, because some of the older periodic inventories reported only 

on timberland, much of the trend reporting in this publication is still focused on 

timberland.

How many trees are in New Hampshire?

Forest land in New Hampshire contains approximately 927 million live trees that 

have a d.b.h. of at least 5 inches. The exact number of trees cannot be determined 

because the estimate is based on only a sample of the total population. The frequency 

estimates are calculated from field measurements of 1,047 forested plots. For 

information on sampling errors, see the report on statistics and quality assurance 

(Gormanson et al. 2018).

How do we estimate a tree’s volume?

To estimate a live tree’s volume, FIA uses volume equations developed for each 

tree species group found within the northeastern United States. Individual tree 

volumes are based on species, diameter, and height. FIA reports volume in cubic feet 

and board feet (International 1⁄4-inch rule). Board-foot volume measurements are 

applicable only for sawtimber-size trees. Some wood products are often measured 

in cords (a stack of wood 8 feet long by 4 feet wide and 4 feet high). A cord of wood 

consists of about 79 to 85 cubic feet of solid wood and the remaining 43 to 49 cubic 

feet are bark and air.

How is forest biomass estimated?

Specific gravity values for each tree species or group of species were developed at the 

Forest Service’s Forest Products Laboratory (Miles and Smith 2009) and were applied 

to FIA tree volume estimates to determine merchantable tree biomass (weight of tree 

bole). Total aboveground live-tree biomass is calculated by adding the biomass for 

stumps, limbs, and tops (Woodall et al. 2011). Live biomass for foliage is currently not 

reported. FIA inventories report biomass weights as oven-dry short tons. Oven-dry 

weight of a tree is the green weight minus the moisture content. Generally, 1 ton of 

oven-dry biomass is equal to 1.9 tons of green biomass.

How do we compare data from different inventories?

New inventories are commonly compared with older datasets to analyze trends or 

changes in forest growth, mortality, removals, and ownership acreage over time 
BACKGROUND | 9

(Powell 1985). A pitfall occurs when the comparison involves data collected under 

different schemes or processed using different algorithms. Recently, significant 

changes were made to the methods for estimating tree-level volume and biomass 

(dry weight) for northeastern states, and the calculation of change components 

(net growth, removals, and mortality) was modified for national consistency. These 

changes focus on improving the ability to report estimates consistently across time 

and space—a primary objective for FIA. Regression models were developed for tree 

height and percent cull to reduce random variability across datasets.

Before the Component Ratio Method (CRM) was implemented, volume and biomass 

were estimated using separate sets of equations (Heath et al. 2009). With CRM, 

determining the biomass of individual trees and forests has become an extension of 

FIA volume estimates, allowing biomass estimates for tree growth, mortality, and 

removals to be obtained not only for live trees, but also for belowground coarse roots, 

standing dead wood, and down woody debris.

Another new method, called the midpoint method, has introduced some differences 

in methodology for determining growth, mortality, and removals for a specified 

sample of trees (Westfall et al. 2009). The new approach involves calculating tree size 

attributes at the midpoint of the inventory cycle (2.5 years for a 5-year cycle) to obtain 

a better estimate for ingrowth, mortality, and removals. Although the overall net 

change component is equivalent under the previous and new evaluations, estimates 

for individual components will be different. For ingrowth, the midpoint method 

can produce a smaller estimate because the volumes are calculated at the 5.0-inch 

threshold instead of using the actual diameter at time of measurement. The actual 

diameter could be larger than 5.0 inches. The estimate for accretion is higher because 

growth from ingrowth, mortality, and removal trees is included. As such, the removals 

and mortality estimates will be higher than before (Bechtold and Patterson 2005).

A word of caution on suitability and availability

FIA does not attempt to identify which lands are suitable or available for timber 

harvesting, especially because suitability and availability are subject to changing laws 

and ownership objectives. Simply because land is classified as timberland does not 

mean it is suitable or available for timber production. Forest inventory data alone 

are inadequate for determining the area of forest land available for timber harvesting 

because laws and regulations, voluntary guidelines, physical constraints, economics, 

proximity to people, and ownership objectives may prevent timberland from being 

available for production.
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Forest Features

| 11

 A moose (Alces alces) and her baby near a spruce/fir forest. Photo by Randall Morin, USDA Forest Service.
12 | FOREST FEATURES

Dynamics of the Forest Land Base

Background

New Hampshire’s diverse, forested landscape includes the transition from maple/

beech/birch forests of the northeastern United States to the spruce/fir forests of 

northern New England. Because forests are essential for wood products, tourism, 

clean water, clean air, wildlife habitat, and wood energy, evaluating change in the 

status and condition of those forests is important. The amount of forest land and 

timberland are vital measures for assessing forest resources and making informed 

decisions about their management and future. Gains or losses in forest area are an 

indication of forest sustainability, ecosystem health, and land use practices because 

they have a direct effect on the amount of goods and services provided.

Forest type is determined by the stocking (relative density) that tree species contribute 

to a sampled area. The forest types used by FIA are based on the types presented by 

Eyre (1980). Related forest types are combined into groups. A map based on FIA plot 

attributes and ancillary data illustrates the spatial distribution of forest-type groups in 

New Hampshire (Fig. 1). This dataset is available for download at https://data.fs.usda.

gov/geodata/rastergateway/forest_type/index.php.

What we found

Forests dominate the land cover across most of New Hampshire. The percentage 

of forest cover generally increases from south to north in New Hampshire (Fig. 1), 

mostly due to more urbanization in the south. In 1948, when FIA completed its first 

inventory in New Hampshire, 84 percent of the State’s area was forested. The 1960 

inventory showed a small increase in forest cover (87 percent of land area). New 

Hampshire’s forest land base then decreased at a slow rate between the 1960s and 

2000s and dropped more precipitously between 2012 and 2017 (Fig. 2). Currently, 

forest covers 83 percent of New Hampshire’s land base. Much of the nearly 280,000-

acre decrease in forest land since 1960 is due to the development of land to meet the 

needs of a growing population, particularly in the southern part of the State because 

of population growth north of Boston, MA (Fig. 3).

The forest land base in New Hampshire is composed of predominantly hardwood 

forest types. The maple/beech/birch forest-type group makes up 52 percent of the 

forest land in the State. Spruce/fir and oak/pine forest-type groups are also well 

represented (Fig. 1), and 64 percent of New Hampshire’s forest land is in large 

diameter stands (Fig. 4).
FOREST FEATURES | 13

Forest-type Group

■ Aspen/birch 

■ Maple/beech/birch 

■ Oak/hickory 

■ Oak/pine 

■ Pinyon/juniper 

■ Spruce/fir 

■ White/red/jack pine

■ Nonforest

■ Water

Projection: New Hampshire State Plane, NAD83.

Sources: USDA Forest Service, Forest Inventory and Analysis program, 2008; 

NLCD 2006 (Fry et al. 2011).

Geographic base data are provided by the National Atlas of the USA®.

FIA data and Tools are available online at https://www.fia.fs.fed.us/tools-data/.

Cartography: R.S. Morin, USDA Forest Service, April 2019.

Figure 1.—Distribution of forest-type groups, New Hampshire, 2008.

4,000 

4,200 

4,400 

4,600 

4,800 

5,000 

1948 1958 1968 1978 1988 1998 2008 2018 

Area (thousand acres) 

Year 

Forest land 

Timberland 

5,200 

Figure 2.—Area of forest land and timberland by inventory year, 

New Hampshire. Error bars represent a 68 percent confidence 

interval around the mean.
14 | FOREST FEATURES

Percentage of 

County Land Area

■<70

■71-79

■80-86

■>86

Projection: New Hampshire State Plane, NAD83.

Sources: USDA Forest Service, Forest Inventory and Analysis program, 1948, 1960, 1973, 1983, 1997, 2007, 2012, and 2017 data.

Geographic base data are provided by the National Atlas of the USA®.

FIA data and Tools are available online at https://www.fia.fs.fed.us/tools-data/.

Cartography: R.S. Morin, USDA Forest Service, April 2019.

1948 1960 1973 1983

1997 2007 2012 2017

Figure 3.—Distribution of relative area of forest land by county and inventory year, New Hampshire. 
FOREST FEATURES | 15

1,800

1,600

1,400

1,200

1,000

800

600

400

200

0

Small Medium Large 

Forest Land Area (thousand acres) 

Stand-size Class 

■ Maple/beech/birch

■ White pine

■Spruce/fir

■ Oak/pine 

■ Oak/hickory 

Figure 4.—Area of forest land for the five most abundant 

forest-type groups by stand-size class, New Hampshire, 

2017. Error bars represent a 68 percent confidence interval 

around the mean.

What this means

With forests covering 83 percent of the land, New Hampshire is the second most 

forested state, but statewide estimates of forest land have decreased by about 2 

percent over the last two decades. The largest proportional losses in forest land 

over this period occurred in Merrimack and Belknap Counties. Future changes in 

New Hampshire’s forest land base will depend on the pace of land development, 

particularly in the southern part of the State.
16 | FOREST FEATURES

Availability and Productivity of Forest Land 

Background

FIA divides forest land into three categories—timberland, reserved forest land, and 

other forest land—to clarify the availability of forest resources and type of forest 

management planning. Two criteria are used to make this determination: reserved 

status (unreserved or reserved) and site productivity (productive or unproductive). 

Forest land that is capable of accumulating wood volume at a rate of at least 20 

cubic feet per acre per year and that is not legally restricted from being harvested 

is classified as timberland. If harvesting is restricted on forest land by statute or 

administrative decision, then it is designated as reserved regardless of its productivity 

class. The harvesting intentions of private forest landowners are not used to determine 

the reserved status. A final category, other forest land, is made up of forest land that is 

unreserved and low in productivity.

What we found

Ninety-four percent of the forest land of New Hampshire meets the definition of 

timberland (Fig. 2), and 77 percent of that timberland is in private ownership. 

Estimates of the amount of timberland have decreased by 1 percent since 1997 (Fig. 

2). Most of the land in the reserved class is in designated natural areas and is located 

on the White Mountain National Forest (see Federal Ownership in Fig. 5). Other 

forest land (i.e., unreserved and unproductive) is rare and accounts for less than 1 

percent of total land (Fig. 6).

What this means

Because the vast majority of the forest land in New Hampshire is classified as 

timberland, it is potentially available for harvesting timber or other forest products. 

It also means that trends observed on timberland are likely to apply to forest land as 

well. The demand for forest products will increase as the number of industries that 

utilize them expands. Therefore, the balance of supply and demand for these forest 

products needs to be closely monitored. Later sections in this report provide more 

details on how much forest land is actively managed for forest products and a more 

accurate estimate of how much timberland is available for harvesting.
FOREST FEATURES | 17

Forest Land Ownership

■ Corporate

■ Family

■ Federal

■ Local

■ Other private

■ State

■ Nonforest

■ Water

Projection: New Hampshire State Plane, NAD83.

Sources: PAD v4.6, 2013; FIA 2009; ALP 2006.

Geographic base data are provided by the National Atlas of the USA®.

FIA data and Tools are available online at https://www.fia.fs.fed.us/tools-data/.

Cartography: R.S. Morin, USDA Forest Service, April 2019.

Figure 5.—Distribution of forest land by owner group, New Hampshire, 2014.

(4,463,025)

77 .9%

(273,696)

4 .8%

(4,464)

0 .1% (986,117)

17 .2%

■■ Timberland

■■ Reserved forest land

■■ Other forest land 

■■ Nonforest 

Figure 6.—Distribution of land by land use, New 

Hampshire, 2017. Values in parentheses are acreages.
18 | FOREST FEATURES

Ownership of Forest Land

Background

How land is managed is primarily the owner’s decision. Therefore, to a large extent, 

landowners determine the availability and quality of forest resources, including 

recreational opportunities, timber, and wildlife habitat. By understanding the 

priorities of forest landowners, the forest conservation community can better help 

owners meet their needs, and in so doing, help conserve the State’s forests for future 

generations. The National Woodland Owner Survey (NWOS; https://www.fia.fs.fed.

us/nwos), conducted by FIA, studies private forest landowners’ attitudes, management 

objectives, and concerns. It focuses on the diverse and dynamic group of owners that 

is the least understood—families, individuals, and other unincorporated groups, 

collectively referred to as “family forest owners.” The NWOS data reported here are 

based on the responses from 146 family forest ownerships from New Hampshire 

that participated between 2011 and 2013 (Butler et al. 2016).1

 Where available, these 

results are compared to the previous iteration of the NWOS implemented between 

2002 and 2006. For comparisons of forest land by ownership category, data are also 

included for the most recent, 2011 through 2017, FIA inventory.

What we found

General Ownership Patterns

Nearly 3 out of every 4 acres (72.2 percent) of the forest land in New Hampshire 

are privately owned. Most of this private forest land, an estimated 2.3 million of the 

3.4 million acres, is owned by family forest owners. Details about this group are 

discussed in the next section. Corporations own an estimated 809,000 acres. Other 

private owners, including conservation organizations and unincorporated clubs and 

partnerships, own an estimated 276,000 acres.

Public owners control 27.8 percent of New Hampshire forest land. The Federal 

government manages an estimated 859,000 acres of forest land, largely in the White 

Mountain National Forest. State forest, park, and wildlife agencies are stewards of 

an estimated 198,000 acres of forest land. Local governments control an estimated 

260,000 acres of forest land in the State. 

Between 2006 and 2017 the estimated forest acreage owned by other private owners 

decreased by 208,000 acres, and State-owned forest acreage decreased by 56,000 acres. 

The estimated areas for all other ownership categories showed net increases ranging 

from 50,000 to 100,000 acres (Fig. 7).

1 Data for the 2017–2018 NWOS are currently being collected with results anticipated for release in late 2019.
FOREST FEATURES | 19

0 1 2 3 

Local 

State 

Federal 

Other private 

Corporate 

Family 

Acres (millions) 

Ownership Group 

■■ 2006

■■ 2013

■■ 2017

Figure 7.—Area of forest land by ownership group and 

inventory year, New Hampshire. Error bars represent a 

68 percent confidence interval around the mean.

Family Forest Ownerships

As of 2013, the date of the latest available data,1

 there are an estimated 39,000 family 

forest ownerships (standard error [SE] = 6.9 percent) across New Hampshire that 

each own at least 10 acres of forest land. The number of family forest ownerships 

remained virtually unchanged since 2006, but the acreage increased by an estimated 

135,000 acres. The average forest holding size of this group in 2013 was 56.1 acres 

per ownership (SE = 11.4 percent). This is slightly higher than in 2006, but the 

estimates are not statistically different. As of 2013, 70.9 percent of these family forest 

ownerships own less than 50 acres of forest land, but 74.0 percent of the family forest 

land is in holdings of at least 50 acres (Fig. 8).

The primary reasons for owning forest land are related to amenity values, such as 

aesthetics, nature, privacy, and wildlife (Fig. 9). Objectives related to financial values, 

including timber production and land investment, are rated as dominant ownership 
20 | FOREST FEATURES

reasons much less frequently. The most common activities on family forest land are 

personal recreation, such as hunting and hiking, and cutting trees for personal use, 

such as firewood (Fig. 10). Due to changes in the wording of the questions, it is not 

possible to directly compare responses to the 2013 NWOS questions on ownership 

objectives to those in the 2006 NWOS.2

The majority of family forest ownerships report participating in the State’s tax program 

and participation is increasing, but far fewer report participating in other assistance 

programs or traditional forestry management activities (Fig. 11). Twenty-six percent of 

the ownerships in New Hampshire, owning 46 percent of the family forest land, report 

receiving forest management advice in the previous 5 years. Fifteen percent of the 

ownerships, owning 41 percent of the family forest land, report having a written forest 

management plan. Fewer than 10 percent of the ownerships report participating in 

easement, cost sharing, or certification programs. Again, comparisons between the 2006 

and 2013 iterations of the NWOS are not feasible due to changes in question wording.2

The average age of family forest owners in New Hampshire is 61.4 years (SE = 5.4 percent). 

Forty-seven percent of the private forest land, or 1.6 million acres, is owned by people 

65 or older (Fig. 12). Between 2006 and 2013, there was a decrease in the percentage of 

owners 65 or older and a marked increase in owners between 55 and 64 years old.

2 More concerted efforts were made to keep the questions as consistent as possible between the 2013 and 

forthcoming 2018 iterations of the NWOS to allow for more accurate analyses of changes over time.

0 20 40 60 80 100 

10–19 

20–49 

50–99 

100–199 

200–499 

500+ 

Percentage of Acreage 

Size of Land Holdings (acres) 

0 20 40 60 80 100 

10–19 

20–49 

50–99 

100–199 

200–499 

500+ 

Percentage of Ownerships 

Size of Land Holdings (acres) 

(A) (B)

■■ 2006

■■ 2013

■■ 2006

■■ 2013

Figure 8.—Percentage of family forest (A) ownerships and (B) area of forest 

land by size of forest land holdings and inventory year, New Hampshire. 

Error bars represent a 68 percent confidence interval around the mean.
FOREST FEATURES | 21

0 20 60 110 

NTFPs* 

Timber 

Hunting 

Investment 

Firewood 

Recreation 

Family 

Legacy 

Water 

Privacy 

Nature 

Wildlife 

Beauty 

Percentage of Ownerships 

Reasons Given for Owning Forest Land 

*Nontimber forest products

(A)

0 20 40 60 80 

NTFPs* 

Timber 

Hunting 

Investment 

Firewood 

Recreation 

Family 

Legacy 

Water 

Privacy 

Nature 

Wildlife 

Beauty 

Percentage of Acreage 

Reasons Given for Owning Forest Land 

100

(B)

40 80 100

Figure 9.—Percentage of family forest (A) ownerships and (B) area of forest 

land by reasons given for owning forest land ranked as very important or 

important, New Hampshire, 2013. Categories are not exclusive. Error bars 

represent a 68 percent confidence interval around the mean.

0 50 100 

Grazing 

Eliminated insects 

Controlled burn 

Wildlife habitat 

Roads 

NTFPs* 

Controlling invasives 

Cut trees-sale 

Trails 

Reduced fire hazard 

Cut trees-personal 

Recreation 

Percentage of Acreage 

Activities within the Last 5 Years 

0 50 100 

Grazing 

Eliminated insects 

Controlled burn 

Wildlife habitat 

Roads 

NTFPs* 

Controlling invasives 

Cut trees-sale 

Trails 

Reduced fire hazard 

Cut trees-personal 

Recreation 

Percentage of Ownerships 

Activities within the Last 5 Years 

*Nontimber forest products

(A) (B)

Figure 10.—Percentage of family forest (A) ownerships and (B) area 

of forest land by activities in the past 5 years, New Hampshire, 2013. 

Categories are not exclusive. Error bars represent a 68 percent confidence 

interval around the mean.
22 | FOREST FEATURES

0 50 100

Certification 

Cost share 

Easement 

Management plan 

Advice 

Tax program 

Percentage of Ownerships 

Participation in Forest Management Programs 

0 50 100 

Certification 

Cost share 

Easement 

Management plan 

Advice 

Tax program 

Perecentage of Acreage 

Participation in Forest Management Programs 

(A) (B)

110

Figure 11.—Percentage of family forest (A) ownerships and (B) area 

of forest land by participation in forest management programs, New 

Hampshire, 2013. Categories are not exclusive. Error bars represent a 68 

percent confidence interval around the mean.

0 20 40 60 80 100 

<45 

45–54 

55–64 

65–74 

75+ 

Percentage of Acreage 

Age of Primary Owner (years) 

0 20 40 60 80 100 

<45 

45–54 

55–64 

65–74 

75+ 

Percentage of Ownerships 

Age of Primary Owner (years) 

■■ 2006

■■ 2013

(A) (B)

■■ 2006

■■ 2013

Figure 12.—Percentage of family forest (A) ownerships and (B) area of 

forest land by age of primary owner and inventory year, New Hampshire. 

Error bars represent a 68 percent confidence interval around the mean.
FOREST FEATURES | 23

What this means

The fate of the forests lies primarily in the hands of those who own and control 

the land. It is therefore critical to understand forest owners and what policies and 

programs can help them conserve the forests for current and future generations. 

Family forest ownerships are the owner group that is the least understood, and the 

fate of their land is arguably the most uncertain. They own their land primarily for 

amenity reasons, but many are actively doing things with their land. Although the 

percentages of ownerships that have received advice and that have written forest 

management plans are higher compared to most other states, there are still significant 

opportunities to help these owners increase their engagement and stewardship of 

their lands. The small parcels held by many landowners and the trend toward more 

landowners with smaller parcels complicate the economics of forest management 

and the delivery of government programs. However, programs such as Tools for 

Engaging Landowners Effectively (http://www.engaginglandowners.org) can help 

the conservation community develop and implement programs more effectively and 

efficiently. Another important trend to watch is the aging of the family forest owners. 

With many of them being relatively advanced in age, this portends many acres of land 

passing on to the next generation in the not too distant future. There are programs 

such as Your Land Your Legacy (http://masswoods.net/monthly-update/your-landyour-legacy-deciding-future-your-land) and Ties to the Land (http://tiestotheland.

org) that are being implemented to help owners meet their bequest goals, but it is 

uncertain who the future forest owners will be and what they will do with their land.

Land Use Change

Background

Forests cover 83 percent of the land area in New Hampshire, providing a critical 

resource and offering a wide range of benefits. FIA characterizes land area by using 

several broad land use categories: forest, rangeland, agriculture, water, developed, 

and other land (wetlands, undeveloped beaches, nonvegetated lands, persisting snow 

and ice). The conversion of forest land to nonforest and water uses is referred to as 

gross forest loss (or diversion), and the conversion of nonforest land and water to 

forest is known as gross forest gain (or reversion). The difference between gross loss 

and gross gain is defined as net forest change. By comparing the land uses on current 

New Hampshire inventory plots (2017) with the land uses recorded for the same plots 

measured during the previous inventory (2012) we can characterize forest landuse change dynamics. To better understand New Hampshire forest land dynamics, 

it is important to explore the underlying land-use changes occurring in the State. 
24 | FOREST FEATURES

Understanding land-use change dynamics is essential for monitoring the 

sustainability of New Hampshire’s forest resources and helps land managers make 

informed policy decisions.

What we found

Total land area in New Hampshire comprises about 5.9 million acres; agricultural 

land uses, along with urban, water, and other nonforest land uses, cover 1.2 million 

acres of the State’s surface area. Between 2012 and 2017 most of the land use in New 

Hampshire either remained forested (79.3 percent) or stayed in a nonforest land use 

(19.1 percent) (Fig. 13). The total area of forest land in New Hampshire declined 

gradually between recent decades, with a 0.4-percent average annual rate of decline 

since the previous inventory. Change plots—for mapping purposes, defined as those 

remeasured plots having land use gain or loss of at least 25 percent—are distributed 

throughout the State, and forest loss plots are more prevalent (Fig. 14).

On the 1.6 percent of surface area where land use changed between inventories (Fig. 

13), the amount of forest diverted to nonforest (65,000 acres) exceeded the amount of 

nonforest that reverted to new forest land (28,000 acres), leading to a slight net loss in 

forest land area (Fig. 15).

■■ Remained forest

■■ Remained nonforest

■■ Forest gain

■■ Forest loss 

19 .1%

79 .3%

0 .5% 1 .1%

Figure 13.—Land use dynamics showing percentage of unchanged 

land, forest loss, and forest gain, New Hampshire, 2012 to 2017. 
FOREST FEATURES | 25

FIA Remeasured Plots

● Forest gain

● Forest loss 

● Remained forest

● Remained nonforest

Figure 14.—Distribution of remeasurement inventory 

plots showing forest gain, forest loss, persisting forest, 

and persisting nonforest, New Hampshire, 2012 to 

2017. Depicted plot locations are approximate.

■■ Agriculture

■■ Water

■■ Developed

■■ Other 

0

Forest Loss

Forest Gain

Area (thousand acres)

10 20 30 40 50 60 70 80

Figure 15.—Gross forest loss and forest gain by land use category, New Hampshire, 

2012 to 2017.
26 | FOREST FEATURES

Forty-six percent of the gross forest loss, or about 30,000 acres, was due to diversion 

to developed land use (Fig. 15). Forest loss also resulted from forest land converted to 

agriculture (17 percent, or 11,000 acres), other land uses (36 percent, or 23,000 acres), 

and water (about 1 percent, or 500 acres). Fifty-one percent of forest gain in New 

Hampshire, or about 14,000 acres, was from agricultural land converting to forest. 

Developed land (49 percent, or about 13,000 acres) provided the remaining source of 

forest reversion (Fig. 15).

What this means

The net loss of forest land reported in this inventory is small, but forest loss is only 

partially offset by forest gain. Gains and losses from multiple causes are driving landuse change dynamics in New Hampshire. Movement between forest and nonforest 

classifications may be a result of land meeting or not meeting FIA’s definition of forest 

land due to small changes in understory disturbance, forest extent, or forest cover. 

Such changes are generally not permanent and may be more prevalent in stands of 

small diameter trees.

Stand Size and Structure—A Growing, 

Maturing Forest

Background

FIA uses tree diameter measurements to assign sampled stands to one of three 

stand-size classes to give a general indication of stand development. Categories are 

determined by the size class that accounts for the most stocking of live trees per 

acre. Small diameter stands are dominated by trees less than 5 inches d.b.h. Medium 

diameter stands have a majority of trees at least 5 inches d.b.h. but less than the 

diameter threshold for large diameter stands. Large diameter stands consist of a 

preponderance of trees at least 9 inches d.b.h. for softwoods and 11 inches d.b.h. for 

hardwoods.

Stocking is a measure of the relationship between the growth potential of a site and the 

occupancy of the land by trees. The relative density (or stocking) of a forest is important 

for understanding growth, mortality, and yield. Five classes of stocking are reported 

by FIA: nonstocked (0–9 percent), poor (10–34 percent), moderate (35–59 percent), 

full (60–100 percent), and overstocked (>100 percent). Stocking levels are examined 

using all live trees and using growing-stock trees only in order to identify the amount of 

growing space that is being used to grow trees of commercial value versus the amount 

that is occupied by trees of little to no commercial value. For a tree to qualify as growing 
 

stock, it must be a commercial species and cannot contain large amounts of cull (rough 

and rotten wood). Te growth potential of a stand is considered to be reached when 

it is fully stocked. As stands become overstocked, trees become crowded, growth rates 

decline, and mortality rates increase. Poorly stocked stands can result from harvesting 

practices or forest growth on abandoned agricultural land; in contrast to moderately 

stocked stands, poorly stocked stands are not expected to grow into a fully stocked 

condition within a practical amount of time for timber production. 

What we found 

In New Hampshire, the distribution of forest land by stand-size class continues the 

trend toward larger diameter stands. A substantial decrease in the area of medium 

diameter stands and a large increase in the area of large diameter stands have 

occurred since 1997 (Fig. 16). Te trend toward increased area of large diameter trees 

is even more pronounced when current timberland estimates are compared with 

those from the 1948 inventory (USDA Forest Service 1954). Large diameter stands 

increased from 37 percent to 64 percent of the timberland area in New Hampshire 

between 1948 and 2017 (Fig. 17). 

Since 1983, forest land area in the moderately and fully stocked classes for all live trees and 

growing-stock trees has increased, and at the same time, overstocked area has decreased 

in New Hampshire (Morin et al. 2011). However, since 2007, the distribution of forest 

land area among stocking classes has remained stable (Fig. 18). Only 34 percent of stands 

are less than fully stocked in New Hampshire as of 2017. A comparison of nonstocked or 

poorly stocked stands for all live trees (Fig. 18) and growing-stock trees (Fig. 19) in 2017 

reveals that the area of such stands is nearly 2.8 times as great for growing-stock trees 

in New Hampshire (600,000 to 218,000 acres). Tis indicates that New Hampshire has 

more than 500,000 acres that are poorly stocked or nonstocked with growing-stock trees, 

but nearly half of those acres are moderately stocked, fully stocked, or overstocked when 

noncommercial species and cull trees are included. In New Hampshire 81 percent of forest 

stands, or about 3.8 million acres, are less than 80 years old (Fig. 20). Te distribution of 

age classes is explored further in the Forest Habitats section starting on p. 77. 

FOREST FEATURES | 27
28 | FOREST FEATURES

0 

500 

1,000 

1,500 

2,000 

2,500 

3,000 

3,500 

1983 1997 2007 2012 2017 

Area of Forest Land (thousand acres) 

Inventory Year 

■■ Small

■■ Medium

■■ Large

Figure 16.—Area of forest land by inventory year and 

stand-size class, New Hampshire. Error bars represent 

a 68 percent confidence interval around the mean.

0 

500 

1,000 

1,500 

2,000 

2,500 

3,000 

3,500 

Small Medium Large

Area of Timberland

(thousand acres) 

Stand-size Class 

27% 

11% 

36% 

25% 

37% 

■■ 64% 1948

■■ 2017

Figure 17.—Area of timberland and percentage 

of total timberland area by stand-size class and 

inventory year, New Hampshire.

0 

500 

1,000 

1,500 

2,000 

2,500 

3,000 

3,500 

Area of Forest Land

(thousand acres)

■■ 1983

■■ 1997

■■ 2007

■■ 2012

■■ 2017

Stocking Class (All Live)

Nonstocked Poorly Moderately Fully Overstocked

Figure 18.—Area of forest land by stocking class of all live 

trees and inventory year, New Hampshire. Error bars represent 

a 68 percent confidence interval around the mean.
FOREST FEATURES | 29

0 

500 

1,000 

1,500 

2,000 

2,500 

3,000 

Area of Forest Land

(thousand acres)

Stocking Class (Growing Stock)

■■ 1983

■■ 1997

■■ 2007

■■ 2012

■■ 2017

Nonstocked Poorly Moderately Fully Overstocked

Figure 19.—Area of forest land by stocking class of growingstock trees and inventory year, New Hampshire. Error bars 

represent a 68 percent confidence interval around the mean.

0 

100 

200 

300 

400 

500 

600 

700 

800 

900 

1,000 

0–20 21–40 41–60 61–80 81–100 >100

Area of Forest Land

(thousand acres) 

Stand-age Class (years) 

■■ Nonstocked

■■ Poorly

■■ Moderately

■■ Fully

■■ Overstocked 

Figure 20.—Area of forest land by stand-age class and 

stocking class of growing-stock trees, New Hampshire, 

2017. Error bars represent a 68 percent confidence 

interval around the mean.
30 | FOREST FEATURES

What this means

The trend of increasing forest land area in large diameter stands demonstrates the 

continuing maturation of New Hampshire forests to stands of larger, older trees. 

An important component of forest biodiversity is complex structural features. The 

decline in area of smaller diameter stands is a concern because many wildlife species 

depend on the habitat provided by young forests. On the other hand, mature stands 

do contain diverse structures due to gap dynamics and the presence of shade-tolerant 

species in the understory. The diversity of tree ages and sizes present in mature forests 

provides a broad range of habitats for wildlife and other organisms and makes forests 

better able to recover from disturbance. 

The shifts in forest area out of nonstocked, poorly stocked, and overstocked stands 

into moderately and fully stocked stands are consistent with the regional trend of 

reforestation and maturation following the widespread land clearing that peaked in 

the late 1800s (Foster et al. 2004). They also suggest that forest management practices 

over the past three decades may have improved the general stocking condition 

across New Hampshire. Most of the forest land is well stocked with tree species of 

commercial importance. From a commercial perspective, continued management of 

these stands is anticipated to keep them growing optimally by preventing them from 

becoming overstocked. From an ecological perspective, New Hampshire has a low 

percentage of “old growth” forests, so consideration may be given to allowing some 

areas to continue growing beyond commercial benchmarks in order to allow the 

development of some ecologically mature forests that support certain wildlife species 

and ecological processes. Although the more than 0.5 million acres of forest land that 

are poorly stocked or nonstocked with commercially important species represent a 

loss of potential growth, these forests contribute to biodiversity. However, the higher 

light levels and open growing conditions in these poorly stocked or nonstocked 

stands may make them more susceptible to invasion by nonnative plant species (e.g., 

common barberry [Berberis vulgaris]), multiflora rose [Rosa multiflora]).
FOREST FEATURES | 31

Number of Trees

Background

A basic component of forest inventory is the number of trees, an estimate that 

is easily understood, reliable, and easy to compare with past inventories. When 

combined with species and size, estimates of number of trees are valuable for showing 

the structure of forests and changes that are occurring over time. Young forests 

generally have many more trees per acre than older forests, but older forests usually 

have much more wood volume (or biomass) than younger forests. 

What we found

Since 1997, the number of trees in the 12-inch and smaller d.b.h. classes has decreased 

while the number of trees in the larger classes has increased (Fig. 21). In general, 

larger diameter classes had higher percentage increases in number of trees than did 

smaller diameter classes (Fig. 22).

For growing-stock trees with a d.b.h. of 5 inches or larger, the most numerous tree 

species in New Hampshire continues to be red maple (scientific names for all tree 

species mentioned in this report are in the appendix). Most of the abundant species 

in New Hampshire (eastern hemlock, balsam fir, sugar maple, northern red oak, 

paper birch, yellow birch, and American beech) decreased slightly in overall numbers 

between 2012 and 2017 while red spruce increased slightly. Red maple, eastern white 

pine, and paper birch had the largest decreases in number of growing-stock trees by 

percentage; all three species decreased by more than 10 percent (Fig. 23).

Numbers of sapling-size trees (1 to 4.9 inches d.b.h.) also decreased for some of the 

abundant tree species in New Hampshire, but paper birch, balsam fir, red spruce, 

eastern white pine, and American beech saplings increased. All noncommercial 

species grouped together continue to be the most abundant saplings other than 

balsam fir and American beech, although their numbers decreased by 7 percent 

between 2012 and 2017. Balsam fir is the most abundant individual sapling species 

in New Hampshire, continuing many years of increases. The largest proportional 

increase in number of saplings was in paper birch (9 percent). Tree species that 

decreased in number of saplings were red maple, yellow birch, eastern hemlock, sugar 

maple, and northern red oak (Fig. 24).
32 | FOREST FEATURES

1983

1997

2007

2012

2017

0 

50 

100 

150 

200 

250 

300 

6 8 10 12 14 16 18 20 21–29 >29 

Number of Trees (millions) 

Diameter Class (inches) 

Figure 21.—Number of growing-stock trees on timberland 

by diameter class and inventory year, New Hampshire.

-20 

-10 

0 

10 

20 

30 

40 

50 

60 

70 

6 8 10 12 14 16 18 20 21–29 >29 

Change in Number of Trees (percent) 

Diameter Class (inches) 

Lorem ipsum

Figure 22.—Percent change in the number of growing-stock 

trees by diameter class, New Hampshire, 2012 to 2017.
FOREST FEATURES | 33

0 25 50 75 100 125 150 

American beech 

Yellow birch 

Paper birch 

Red spruce 

Northern red oak 

Sugar maple 

Balsam fir 

Eastern hemlock 

Eastern white pine 

Red maple 

Number of Growing-stock Trees (millions) 

Species 

-11% 

-16% 

-9% 

-2% 

-6% 

-4% 

+4% 

-18% 

-9% 

-7% 

■■ 1983

■■ 1997

■■ 2007

■■ 2012

■■ 2017

Figure 23.—Number of growing-stock trees on timberland 

by species and inventory year, New Hampshire. Percentages 

indicate change from 2012 to 2017.

0 200 400 600 

Northern red oak 

Paper birch 

Eastern white pine 

Sugar maple 

Eastern hemlock 

Yellow birch 

Red spruce 

American beech 

Noncommercial species* 

Red maple 

Balsam fir 

Number of Saplings (millions)

Species 

+2%

-6%

-7%

+6%

+7%

-11%

-8%

-7%

+4%

-7%

*Includes striped maple, eastern 

hophornbeam, pin cherry,

and other species with poor form.

+9%

■■ 1997

■■ 2007

■■ 2012

■■ 2017

Figure 24.—Number of saplings (1 to 4.9 inches in diameter) 

on timberland by species and inventory year, New Hampshire. 

Percentages indicate change from 2012 to 2017.
34 | FOREST FEATURES

What this means

Saplings in today’s forest are a prime indicator of the composition of the future 

forest. Saplings eventually replace large trees that are harvested or killed by insects, 

diseases, or weather events. The increasing dominance of American beech will have 

an impact on the future species composition of New Hampshire forests. Similarly, 

balsam fir is increasing in understory dominance. The high relative sapling abundance 

of noncommercial species may be a concern for timber management. Projections 

of future compositional changes are complicated by the potential impacts of climate 

change on the distributions of different tree species.

Carbon Stocks

Background

Among terrestrial ecosystems, forests contain the largest reserves of sequestered 

carbon. The accumulation of carbon in forests helps to mitigate emissions of carbon 

dioxide to the atmosphere from sources such as wildfires or the burning of fossil fuels. 

Carbon accumulates in growing trees via the photosynthetically driven production 

of structural and energy-containing organic (carbon) compounds that primarily 

accumulate in trees as wood; roughly 50 percent of tree biomass is carbon (based 

on dry weight). Over time, this stored carbon also accumulates in standing dead 

trees, down woody materials, litter, and forest soils. For most forests, the understory 

grasses, forbs, and nonvascular plants, as well as animals, represent minor pools of 

carbon stocks. FIA uses a combination of field measurements and models to estimate 

forest carbon stocks. Procedures for the estimation of carbon are detailed by the U.S. 

Environmental Protection Agency (2018).

What we found

Total forest ecosystem carbon stocks in New Hampshire are an estimated 546.8 

million short tons. This represents a small decrease of 0.5 percent in total forest 

carbon stocks since 2012. Soil organic carbon and live trees are the largest pools and 

combined account for 90 percent of forest carbon (Fig. 25). Most of New Hampshire’s 

forest carbon stocks are in stands between 61 and 100 years old (65 percent of 

total forest carbon). Considerably less carbon is found in stands younger than 61 

years old (26 percent) and older than 100 years (9 percent). As a per acre estimate, 

average carbon density (short tons per acre) in the live biomass pools (live trees and 

understory) increases with stand age and net accumulation is greater within live 

biomass than in the dead wood, litter, and soil pools (Fig. 26). The maple/beech/birch 
FOREST FEATURES | 35

forest-type group contained the majority of total forest carbon (52 percent, or more 

than 286 million short tons), as it covers a large amount of the forest land (Fig. 27a). 

On a per acre basis, however, carbon density was highest in the oak/hickory foresttype group (127 short tons per acre), with the oak/pine forest-type group next at 117 

short tons per acre (Fig. 27b). 

Soil organic

carbon, 58% 

Forest floor/litter, 6% Down dead wood, 2%

Understory, 1%

Standing dead trees, 1%

Saplings, 3%

Top/limbs, 4%

Bole, 19%

Stump, 1%

Coarse roots, 5%

Live saplings

and trees 32% 

Figure 25.—Percentage of carbon stocks on forest land 

by forest ecosystem component, New Hampshire, 2017.

0

20

40

60

80

100

120

140

0–20 21–40 42–60 61–80 81–100 >100

Carbon Density (short tons per acre)

Stand-age Class (years)

■ Live biomass C ■ Dead wood C ■ Litter C ■ Soil organic C

Figure 26.—Aboveground carbon stocks per acre for live biomass, dead wood, 

and soil components on forest land by stand-age class, New Hampshire, 2017.
36 | FOREST FEATURES

0 50 100 150 200 250 300

Carbon Stocks (million short tons)

Forest-type Group

0 20 40 60 80 100 120 140

Maple/beech/birch

Oak/hickory 

White/red/jack pine

Spruce/fir

Oak/pine

Aspen/birch

Elm/ash/cottonwood

All other forest-type groups Forest-type Group

Carbon Density (million short tons per acre)

Maple/beech/birch

Oak/hickory 

White/red/jack pine

Spruce/fir

Oak/pine

Aspen/birch

Elm/ash/cottonwood

All other forest-type groups

(A)

(B)

■ Live biomass C

■ Dead wood C

■ Litter C

■ Soil organic C

■ Live biomass C

■ Dead wood C

■ Litter C

■ Soil organic C

Figure 27.—(A) Carbon stocks by forest-type group, and (B) carbon 

stocks per acre by forest-type group, New Hampshire, 2017.
FOREST FEATURES | 37

What this means

Forest carbon stocks in New Hampshire have decreased slightly since 2012, with the 

main driver being the loss of forest land. Soil organic carbon accounts for the largest 

loss of carbon when forest is lost to other land uses. Despite the overall decline of 

forest carbon stocks, carbon in live trees has increased. The live tree carbon pool 

represents the best opportunity to increase carbon stocks in the future, as this pool 

can be most affected by forest management. Most forest carbon in New Hampshire is 

found in moderate-aged stands dominated by relatively long-lived species, suggesting 

that forest carbon stocks will continue to increase as stands mature and accumulate 

carbon in aboveground and belowground components. As mitigating U.S. greenhouse 

gas emissions becomes increasingly important, an understanding of trends in carbon 

sequestration and storage will be an essential tool for forest managers.

Biomass

Background

The increasing interest in carbon dynamics for questions related to carbon 

sequestration, emissions reduction targets, production of biofuels, and forest fire 

fuel loadings makes estimates of biomass a critical component of the FIA program. 

FIA defines aboveground biomass as the weight of live trees composed of the boles, 

aboveground portion of stumps, tops, and limbs (but excluding foliage). Due to 

increases in tree volume, New Hampshire forests contribute significantly to carbon 

sequestration (uptake and storage).

What we found

The forest land of New Hampshire has an estimated 291.6 million dry tons of 

aboveground tree biomass, with biomass per acre averaging 61.5 tons per acre of 

forest land. The distribution of biomass per acre on forest land is generally highest in 

southern New Hampshire (Fig. 28). The largest portion of the aboveground biomass 

is in the boles of growing-stock trees (62 percent), but this is also the part of the tree 

resource that can be converted into valuable wood products. The other 38 percent of 

the biomass is in tops, limbs, stumps, cull trees, or trees of noncommercial species 

(Fig. 29).

Total live dry biomass on timberland in New Hampshire has increased by 32 percent 

since 1983 (from 148 million to 196 million dry tons), primarily due to the increasing 

size of sawtimber trees. In contrast, biomass decreased in poletimber-size trees during 

this time period (Fig. 30).
 

Biomass of Live 

Trees on Forest Land 

(tons per acre) 

■ 0–25 

■ >25–40 

■ >40–60 

■ >60 

■■ Nonforest 

■■ Water 

Projection: New Hampshire State Plane, NAD83. 

Sources: USDA Forest Service, Forest Inventory and Analysis program, 2009; 

NLCD 2006 (Fry et al. 2011). 

Geographic base data are provided by the National Atlas of the USA®. 

FIA data and Tools are available online at https://www.fia.fs.fed.us/tools-data/. 

Cartography: R.S. Morin, USDA Forest Service, February 2019. 

Figure 28.—Live-tree biomass (dry tons) per 

acre of trees 1 inch in diameter and larger on 

forest land, New Hampshire, 2009. 

62% 

8% 

9% 

3% 

Total biomass = 291,567,000 dry tons 

■■ Boles of growing-stock trees ( ̃5 inches in diameter) 

■■ Tops/limbs/stumps of growing-stock trees 

■■ Saplings (<5 inches in diameter) 

■■ Boles of nongrowing-stock trees ( ̃5 inches in diameter) 

■■ Tops/limbs/stumps of nongrowing-stock trees 

18% 

Figure 29.—Percentage of live-tree biomass (trees 

1 inch in diameter and larger) on forest land by 

aboveground component, New Hampshire, 2017. 

38 | FOREST FEATURES 
FOREST FEATURES | 39

0 

5,000 

10,000 

15,000 

20,000 

25,000 

6 10 14 18 22 26 30 34 38 42+

Biomass (thousand dry tons)

Diameter Class (inches)

0 

1,000 

2,000 

3,000 

4,000 

5,000 

6,000 

7,000 

8,000 

9,000 

6 10 14 18 22 26 30 34 38 42+

Biomass (thousand dry tons)

Diameter Class (inches)

Hardwoods, 1983

Hardwoods, 1997

Hardwoods, 2007

Hardwoods, 2012

Hardwoods, 2017

Softwoods, 1983

Softwoods, 1997

Softwoods, 2007

Softwoods, 2012

Softwoods, 2017

(A) (B)

Figure 30.—Distribution of live-tree biomass (trees 1 inch in diameter and larger) in (A) hardwoods 

and (B) softwoods on timberland by diameter class and inventory year, New Hampshire.

What this means

The forests of New Hampshire are continuing to accumulate biomass as they mature. 

Because most of the biomass is contained in the boles of growing-stock trees and 

most of the gains in biomass stocks are found in these higher value sawtimber-size 

trees, only a fraction of the accumulated material is available for use as whole tree 

chips for large wood fuel users. If the demand for biomass increases with increased 

demand in heating, power production, and (potentially) the production of liquid 

fuels, the wood-using market would become more competitive. This creates an 

opportunity for enhancing forest management practices to benefit both traditional 

forest products supplies and those for bioenergy. The Biomass Energy Resource 

Center produced a detailed report on supply and sustainability of available low-grade 

wood for New England (Biomass Energy Research Center 2019).

Private forest landowners are the holders of the majority of the forest biomass in 

New Hampshire (71 percent). Thus they play an important role in sustaining this 

resource. Currently, forest landowners are not financially compensated for the carbon 

sequestration service provided by the trees on their land. However, the markets for 

forest carbon sequestration are growing, so this scenario could change in the future. 

If carbon trading and biomass production become more common, reliable estimates 

of biomass and carbon in forests, both in the aboveground biomass and in soils, will 

become more important. The future of this scenario depends on political decisions 

and prices for energy-producing fuels including crude oil and natural gas.
40 | FOREST FEATURES

Volume of Growing-stock Trees

Background

To assess the amount of wood potentially available for commercial products, 

FIA computes growing-stock volumes for trees growing on timberland that meet 

requirements for size, straightness, soundness, and species. Growing-stock volume 

includes only commercial tree species with a d.b.h. of 5 inches or larger and does 

not include rough, rotten, or dead trees. The forest products industry relies on this 

estimate of growing-stock volume as its resource base. Current volumes and changes 

in volume over time can characterize forests and reveal important resource trends. 

This is especially critical with respect to trend information because many past FIA 

inventories have only growing-stock estimates available.

What we found

The total growing-stock volume in New Hampshire increased steadily from the 1940s 

to 2012, but in recent years total growing-stock has begun to decrease. The 2017 

estimate of 9.5 billion cubic feet is a substantial increase from the 1983 estimate of 8.0 

billion cubic feet but indicates a return almost to 2007 levels (9.4 billion cubic feet) 

(Fig. 31). The decrease in growing-stock volume between 2012 and 2017 is in contrast 

to the 1 to 4.5 percent annual increases in previous decades. Distribution of growingstock volumes by diameter class from the current and four previous inventories 

reveals a steady shift toward larger diameter trees (Fig. 32). During the most recent 

inventory (2017), volume increased in the two largest d.b.h. classes but decreased in 

the diameter classes below 18 inches (Fig. 33).

In general, total volumes are higher in southern New Hampshire than in northern New 

Hampshire. Volume per acre varies spatially by species (Fig. 34). Sugar maple density 

is highest in northern New Hampshire. Red maple is distributed throughout the State, 

with the highest volumes in the southern regions. Eastern white pine, northern red oak, 

and eastern hemlock are most concentrated in southern New Hampshire. 

The level of growing-stock volume on timberland in New Hampshire averages over 

2,100 cubic feet per acre. Of this volume, 58 percent is in hardwood species and 42 

percent is in softwood species. Red maple (25 percent), northern red oak (22 percent), 

sugar maple (14 percent), and yellow birch (9 percent) make up 70 percent of the 

hardwood growing-stock volume. Eastern white pine (51 percent), eastern hemlock 

(24 percent), red spruce (13 percent), and balsam fir (10 percent) account for 98 

percent of softwood growing-stock volume (Fig. 35).
FOREST FEATURES | 41

0 

1,000 

2,000 

3,000 

4,000 

5,000 

6,000 

7,000 

Softwoods Hardwoods 

Growing-stock Volume (million cubic feet)

■■ 1948

■■ 1966

■■ 1973

■■ 1983

■■ 1997

■■ 2007

■■ 2012

■■ 2017

Figure 31.—Growing-stock volume on timberland by species 

group and inventory year, New Hampshire. Error bars represent 

a 68 percent confidence interval around the mean.

1983

1997

2007

2012

2017

0 

200 

400 

600 

800 

1,000 

1,200 

1,400 

1,600 

1,800 

6 8 10 12 14 16 18 20 

Growing-stock Volume (million cubic feet)

Diameter Class (inches)

Figure 32.—Growing-stock volume on timberland by diameter 

class (2-inch intervals) and inventory year, New Hampshire. Error 

bars represent a 68 percent confidence interval around the mean. 
42 | FOREST FEATURES

■1983 to 1997

■1997 to 2007

■2007 to 2012

■2012 to 2017

-30 

-20 

-10 

0 

10 

20 

30 

40 

50 

60 

70 

6 8 10 12 14 16 18 20 

Change (percent)

Diameter Class (inches)

Figure 33.—Percent change in growing-stock volume on 

timberland by diameter class (2-inch intervals) and inventory 

year, New Hampshire.
FOREST FEATURES | 43

Total

■■ <1,000

■■ 1,000–1,500

■■ 1,500–2,000

■■ 2,000–2,500

■■ >2,500

■■ Nonforest

■■ Water

Projection: New Hampshire State Plane, NAD83.

Sources: USDA Forest Service, Forest Inventory and Analysis program, 2009; NLCD 2006 (Fry et al. 2011).

Geographic base data are provided by the National Atlas of the USA®.

FIA data and Tools are available online at https://www.fia.fs.fed.us/tools-data/.

Cartography: R.S. Morin, USDA Forest Service, February 2014.

Volume on Forest Land (cubic feet per acre)

Sugar Maple

■■ <100

■■ 100–250

■■ 250–500

■■ 500–1,000

■■ >1,000

■■ Nonforest

■■ Water

Eastern White Pine

■■ <50

■■ 50–200

■■ 200–500

■■ 500–1,000

■■ >1,000

■■ Nonforest

■■ Water

Eastern Hemlock

■■ <50

■■ 50–200

■■ 200–400

■■ 400–800

■■ >800

■■ Nonforest

■■ Water

Red Maple

■■ <75

■■ 75–200

■■ 200–400

■■ 400–600

■■ >600

■■ Nonforest

■■ Water

Northern Red Oak

■■ <25

■■ 25–100

■■ 100–200

■■ 200–400

■■ >400

■■ Nonforest

■■ Water

Figure 34.—Cubic-foot volume per acre on forest land for major tree 

species (for trees 5 inches in diameter or larger), New Hampshire, 2009.
44 | FOREST FEATURES

0 500 1,000 1,500 2,000 2,500 

Black oak 

White oak 

Sweet birch 

Quaking aspen 

White ash 

Balsam fir 

American beech 

Red spruce 

Paper birch 

Yellow birch 

Sugar maple 

Eastern hemlock 

Northern red oak 

Red maple 

Eastern white pine 

Growing-stock Volume (million cubic feet)

Species

■■ 1997

■■ 2007

■■ 2012

■■ 2017

Figure 35.—Growing-stock volume on timberland by species 

and inventory year, New Hampshire. Error bars represent a 

68 percent confidence interval around the mean.

Overall, eastern white pine has 50 percent more growing-stock volume than the next 

most abundant species, red maple, followed by northern red oak, eastern hemlock, 

and sugar maple. These five species make up 67 percent of the total growing-stock 

volume in New Hampshire. Species that showed modest increases in growing-stock 

volume between 2012 and 2017 were northern red oak and red spruce, each of 

which increased by more than 5 percent. In contrast, paper birch and white oak both 

decreased by more than 5 percent (Fig. 35).

When board-foot volume is estimated, the order of the four species with the highest 

volumes is slightly different from the order for growing-stock volume. Eastern white pine 

remains the leading species by a large margin, but northern red oak replaces red maple 

as the second highest (Fig. 36). Eastern white pine makes up over 30 percent of the total 

sawtimber volume in New Hampshire. Red spruce had the largest gain in sawtimber 

volume between the 2012 and 2017 inventories (12 percent), and white oak showed the 

largest decrease (33 percent). Total board-foot volume has remained stable since 2012.
FOREST FEATURES | 45

0.0 2.0 4.0 6.0 8.0 10.0 12.0 

Black oak 

White oak 

Quaking aspen 

Balsam fir 

Paper birch 

White ash 

American beech 

Red spruce 

Yellow birch 

Sugar maple 

Eastern hemlock 

Red maple 

Northern red oak 

Eastern white pine 

Sawtimber Volume (billion board feet)

Species

■■ 1997

■■ 2007

■■ 2012

■■ 2017

Figure 36.—Board-foot volume of sawtimber on timberland 

by species and inventory year, New Hampshire. Error bars 

represent a 68 percent confidence interval around the mean.

What this means

The total volume of timber resources in New Hampshire has started to decrease for the 

first time since FIA began doing inventories in the State in 1948. The slight decrease in 

timberland area along with a slowing rate of increase in total growing-stock volumes has 

resulted in this reduction in total timber volume, and growth rates may decrease further 

as the forest ages. Even though the per acre rate of volume increase is leveling off, the 

forests of New Hampshire are adding value at an increasing rate due to growth that is 

occurring on the higher valued trees. Landowners and the forest products industry can 

benefit from the increase in value, but care in management and harvesting practices 

will be important to ensure a steady supply of desirable species into the future as the 

population of poletimber-size trees replaces the sawtimber-size trees.
46 | FOREST FEATURES

Sawtimber Quality

Background

The value of a tree in the forest products market is determined by its species, size, 

and quality. High quality timber is generally characterized by a large diameter and 

the absence of defects such as knots, wounds, and poor form. Timber used in the 

manufacture of cabinets, furniture, flooring, or other millwork is the most valuable. 

Lower quality trees are utilized as pallets, pulpwood, or fuelwood. The quality of 

an individual tree can be influenced by species as well as diameter, growth rate, 

and management practices. According to FIA standards, hardwood trees must 

have a d.b.h. of at least 11 inches to qualify as sawtimber. FIA assigns tree grades to 

sawtimber-size trees as a measure of quality. Tree grade is based on tree diameter 

and the presence or absence of defects such as knots, decay, and curvature of the bole 

(sweep and crook). These grades have parallels to log grades used by sawmills, but 

they are not identical. Quality decreases from grade 1 (high grade lumber) to grade 3. 

Grade 4 is assigned to material for ties and local use. 

What we found

The proportion of hardwood sawtimber volume in the highest quality categories 

(tree grades 1 and 2) decreased in New Hampshire between 2012 and 2017. There 

are currently 5 billion board feet in tree grades 1 and 2 in New Hampshire. The 

proportion of volume in tree grades 3 and tie/local use increased by 3 percent 

between the two latest inventories (Fig. 37).

Eastern hemlock and red spruce are the only species among those leading by 

sawtimber volume with more than 50 percent of their volume in tree grades 1 and 

2. Northern red oak, sugar maple, and white ash have at least 30 percent of their 

sawtimber volume in grades 1 and 2. In contrast, red maple has less than 20 percent 

and American beech has less than 1 percent of their sawtimber volume in grades 1 

and 2 (Fig. 38).

What this means

The quality and total volume of saw logs in New Hampshire have declined slightly 

since the last inventory, and board-foot volume has started to decrease for many 

species. Changes in species composition point toward continued reductions in tree 

quality into the future. Many beech trees contain cankers and large amounts of rotten 

wood due to the impacts of beech bark disease, an insect-fungus complex involving 

the beech scale insect (Cryptococcus fagisuga) and the exotic canker fungus Neonectria 
FOREST FEATURES | 47

coccinea var. faginata or the native Neonectria galligena. Red maple typically has more 

defects than other species. The species with the highest proportion of low-grade 

volume, American beech, is also the most abundant hardwood sapling species in the 

State. Red maple has the second highest proportion of low-grade volume and is also a 

relatively low value species.

0 

2 

4 

6 

8 

10 

12 

14 

16 

18 

1997 2007 2012 2017

Hardwood Volume (billion board feet)

Inventory Year

51%

10%

23%

15%

15%

23%

39%

23%

13%

24%

42%

22% 23% 

44%

22%

11%

■■ Tie/local use

■■ Grade 3

■■ Grade 2

■■ Grade 1

Figure 37.—Hardwood volume by inventory year and tree 

grade, New Hampshire. Percentages of total volume for each 

grade are also indicated by inventory year. Percentages may 

not add to 100 because of rounding. 

■■ Grade 1

■■ Grade 2

■■ Grade 3

■■ Tie/local use

4 

20 

96 

3 

8 

97 

9 

23 

1 

3 

22 

29 

15 

22 

19 

24 

24 

38 

38 

04 

58 

50 

03 

50 

38 

6 

62 

36 

12 

25 

21 

21 

15 

93 

10 

0 20 40 60 80 100 

Eastern white pine 

Northern red oak 

Eastern hemlock 

Red maple 

Sugar maple 

Red spruce 

Yellow birch 

White ash 

American beech 

Paper birch 

Percentage of Saw-log Volume 

Species 

Figure 38.—Percentage of saw-log volume on timberland 

by species and tree grade, New Hampshire, 2017.
48 | FOREST FEATURES

Average Annual Net Growth and Removals

Background

Forests are a renewable resource if they are managed to provide a constant supply of 

useful products without diminishing long-term productivity. The rate of growth is 

an indicator of the overall condition of a stand as well as forest health, successional 

stage, and tree vigor. Average annual net growth (gross growth minus mortality) is 

calculated by measuring trees at two points in time and determining the average 

annual change over the time period. Net growth is negative when mortality exceeds 

gross growth. A useful measure to assess growth is the ratio of annual net growth 

to current inventory volume. Average annual net growth estimates are based on the 

change in volume of growing stock on timberland between inventories. The terms 

average annual net growth and net growth are used interchangeably.

What we found

Since 2012, average annual net growth has decreased in New Hampshire (Fig. 39). Net 

growth of growing-stock trees averaged 181 million cubic feet annually as of 2017, 

about 2 percent of growing-stock volume on timberland. In comparison to previous 

inventories, annual net growth as a percentage of growing-stock volume has been 

generally decreasing from 1973 to 2017 (Fig. 40). In 2017, about 55 percent of annual 

net growth was in hardwoods and 81 percent was on privately owned land.

The nine species with the greatest growing-stock volume accounted for 85 percent of 

the average annual net growth of growing stock on timberland as of 2017. The ratio 

of net growth to removals averaged 1.9:1.0, which is a small increase from what was 

reported for 2012 (1.7:1.0). Variation between species was considerable. Net growth 

exceeded removals for all major species (Fig. 41). Northern red oak, eastern hemlock, 

and white ash had the highest growth-to-removals ratios at 4.3:1.0, 3.8:1.0, and 3.0:1.0, 

respectively. The largest positive changes in growth-to-removals ratios between 2012 

and 2017 were in white ash (from 1.3 to 3.0) and red spruce (from 1.0 to 2.6). In 

contrast, changes in the growth-to-removals ratio for American beech (from 2.7 to 2.0) 

and eastern white pine (from 1.8 to 1.4) were negative (Morin et al. 2015a).
FOREST FEATURES | 49

■■ Net growth

■■ Removals

■■ Mortality

0 

50 

100 

150 

200 

250 

1948 1960 1973 1983 1997 2007 2012 2017 

Growing-stock Volume

(million cubic feet)

Inventory Year 

1.8:1 

3.7:1 

2.2:1 

1.3:1 1.1:1 

1.7:1 2.2:1 

1.9:1 

Figure 39.—Growing-stock volume and growth-to-removals 

ratio of growing stock on timberland by inventory year and 

growth category, New Hampshire. Error bars represent a 68 

percent confidence interval around the mean.

■■ Hardwoods

■■ Softwoods

■■ Total

0 

0.5 

1 

1.5 

2 

2.5 

3 

3.5 

4 

4.5 

1960 1973 1983 1997 2007 2012 2017

Net Growth as a Percentage

of Growing-stock Volume

Inventory Year 

Figure 40.—Average annual net growth of growing stock 

on timberland as a percentage of growing-stock volume, 

by inventory year and forest type, New Hampshire.
50 | FOREST FEATURES

■■ Net growth

■■ Removals

0 10 20 30 40

Sweet birch 

Red spruce 

White ash 

Yellow birch 

American beech 

Sugar maple 

Eastern hemlock 

Northern red oak 

Red maple 

Eastern white pine 

Growing-stock Volume (million cubic feet)

Species

1.4:1 

1.8:1 

4.3:1 

3.8:1 

1.1:1 

2.0:1 

1.7:1 

3.0:1 

2.6:1 

G/R for all species = 1.9:1 

Figure 41.—Average annual net growth, average annual removals, 

and growth-to-removals ratio (G/R) of growing-stock trees for 

major species on timberland, New Hampshire, 2017. Error bars 

represent a 68 percent confidence interval around the mean.

What this means

The well-stocked stands in the current forests of New Hampshire developed as a result 

of the growth-to-removals ratios being well above 1.0:1.0 for most of the second half of 

the 20th century. More recently, the forests of New Hampshire have matured and the rate 

of growth has slowed (Fig. 39). At the current rates of growth, mortality, and removals, 

the forests of New Hampshire are increasing in volume at a rate of roughly 2 percent per 

year. This rate is higher on private lands, most likely due to a larger proportion of public 

lands being located on high elevation, low productivity sites. Fortunately, more than 95 

percent of the removals volume is due to harvesting and not land use change. Trees can 

be expected to regenerate as long as the land is not developed.

A comparison of the growth-to-removals ratios of individual species to the average 

for all species is an indicator of sustainable harvesting. The low growth-to-removals 

ratio of sugar maple (1.1:1.0) suggests that this species could be decreasing in 

abundance. In contrast, red spruce is among the species with the highest number of 

saplings and appears to be increasing in numbers.

Average Annual Mortality

Background

Mortality is a natural part of stand development in healthy forest ecosystems. 

Many factors contribute to mortality, including competition, succession, insects, 

disease, fire, human activity, and drought. Mortality is often initiated by one causal 

agent (inciting factor) that is followed by other contributing stress factors, making it 
FOREST FEATURES | 51

difficult to identify the underlying cause. Although mortality is a natural event in a 

functional forest ecosystem, dramatic increases in mortality can be an indication of 

forest health problems. Average annual growing-stock mortality estimates represent 

the average cubic-foot volume of sound wood that dies each year between inventories. 

Biotic and abiotic disturbances can stress forests either as inciting factors or as 

contributors to mortality.

What we found

The estimated average annual mortality for growing-stock trees in New Hampshire for 

2017 was 69 million cubic feet, which is approximately 0.7 percent of growing-stock 

volume. This is a small decrease compared to the rates reported for 2007 and 2012. In 

most inventory periods, softwoods have a higher mortality rate than hardwoods, but 

since 2012, the hardwood mortality rate has been higher (Fig. 42). The mortality rates 

are similar to other states in the region, such as Maine (1.0 percent) (McCaskill et al. 

2011) and New York (1.1 percent) (Widmann et al. 2015).

Mortality decreased across nearly all species between 2012 and 2017 in New 

Hampshire, but the decreases were generally not statistically significant (Fig. 43). 

Most of the abundant species in New Hampshire have relatively low mortality 

rates that are below the 0.7 percent annual average for all tree species combined. In 

contrast, balsam fir and paper birch have mortality rates that are more than triple the 

statewide average (Fig. 44).

■■ Hardwoods

■■ Softwoods

■■ Total

0.0 

0.2 

0.4 

0.6 

0.8 

1.0 

1.2 

1960 1973 1983 1997 2007 2012 2017

Mortality as a Percentage of

Growing-stock Volume

Inventory Year

Figure 42.—Average annual mortality of growing stock on 

timberland as a percentage of growing-stock volume, by 

inventory year and forest type, New Hampshire.
52 | FOREST FEATURES

0 5 10 15 20 25

White ash 

Sugar maple 

Eastern hemlock 

American beech 

Yellow birch 

Northern red oak 

Red spruce 

Eastern white pine 

Red maple 

Paper birch 

Balsam fir 

Average Annual Mortality (million cubic feet)

Species

■■ 1997

■■ 2007

■■ 2012

■■ 2017

Figure 43.—Average annual mortality of growing stock on timberland 

for major species by inventory year, New Hampshire. Error bars 

represent a 68 percent confidence interval around the mean.

0.2 

0.2 

0.4 

0.6 

0.4 

0.9 

0.5 

1.2 

2.5 

2.8 

0 1 2 3 5

Eastern hemlock 

Northern red oak 

Sugar maple 

Eastern white pine 

Red spruce 

Red maple 

Yellow birch 

American beech 

Balsam fir 

Paper birch 

Average Annual Mortality Rate (percent)

Average for all species (2017) = 0.7%

■■ 2007

■■ 2012

■■ 2017

4

Species

Figure 44.—Average annual mortality rate for major species by 

inventory year, New Hampshire. Labeled values are for 2017.
 

What this means 

Tree mortality rates in New Hampshire are comparable to those in surrounding states. 

Some of the mortality can be explained by stand dynamics (e.g., competition and 

succession) and the impacts of insects and diseases that afect specifc species (e.g., 

beech bark disease on American beech). In the normal maturation process, some 

trees lose vigor and eventually die from being outcompeted or succumb to insects and 

disease during their weakened state; this is especially apparent in trees with a d.b.h. of 

12 inches or less. 

Most species in New Hampshire have low mortality rates, but some have elevated rates. 

Species such as balsam fr and paper birch have increased in overall mortality rates. 

American beech has been heavily impacted by beech bark disease for many decades and 

is now showing reductions in mortality (see “Beech Bark Disease” starting on p. 66). 

Weather-related events that afected tree health during this time include the afer-efects 

of the 1998 ice storm and droughts during 1999 and 2001. Recovery from the ice storm 

was particularly poor for beech and paper birch trees. Drought efects were especially 

severe for species with shallow root systems such as birch and beech, or for species that 

typically grow on sites with shallow soils such as balsam fr and red spruce. Additional 

health problems were observed from forest tent caterpillar (Malacosoma disstris) 

defoliation, spruce winter injury, and balsam woolly adelgid (Adelges piceaea). Recovery 

afer stress events ofen depends on soil fertility; trees growing on calcium-rich sites are 

more likely to recover (Schaberg et al. 2006, Shortle and Smith 1988). 

Species Composition 

Background 

Te species composition of a forest is the result of the interaction over time of 

multiple factors, such as climate, soils, disturbance, and competition among tree 

species. Causes of forest disturbance in New Hampshire include ice storms, logging, 

droughts, insects and diseases, and land clearing followed by abandonment. Te 

species composition of the growing-stock volume and large diameter trees represents 

today’s forest, while the species composition of the smaller diameter classes represents 

the potential future forest. Comparisons of species composition by diameter class can 

provide insights into potential changes in future overstory species composition. 

FOREST FEATURES | 53
54 | FOREST FEATURES

What we found

In New Hampshire, balsam fir is the most numerous sapling species on forest land, 

accounting for 22 percent of all saplings (trees 1 to 4.9 inches d.b.h.), followed by 

American beech (13 percent) and red maple (11 percent) (Fig. 45). Noncommercial 

tree species combined also represent a large portion of saplings at 9 percent, which 

is an increase of 2 percentage points since the 2012 inventory (Morin et al. 2015a). 

Striped maple is the most numerous of the noncommercial species, followed by pin 

cherry and eastern hophornbeam. Eastern white pine is the dominant species in all 

diameter classes 16 inches d.b.h. and larger, but it is poorly represented in the sapling 

classes (less than 5 percent). Other species that have a lower representation in the 

sapling classes compared to the larger diameter classes include eastern hemlock and 

sugar maple. In contrast, American beech, balsam fir, and red spruce make up a 

higher proportion of total saplings relative to their share of larger trees (Fig. 45).

0 

20 

40 

60 

80 

100 

2 6 10 14 18 21–29

Individual Species as a Percentage of Total Number of Trees in Class

Diameter Class (inches)

■Noncommercial hardwoods

■Paper birch

■Red spruce

■American beech

■Yellow birch

■Balsam fir

■Sugar maple

■Northern red oak

■Other commercial species

■Eastern hemlock

■Red maple

■Eastern white pine

>29

Figure 45.—Species composition by diameter class 

on forest land, New Hampshire, 2017.
FOREST FEATURES | 55

What this means

Conditions in the understory of older forests favor the reproduction of shade-tolerant 

species, as shown by the higher proportion of American beech, balsam fir, and red 

spruce in the sapling diameter classes compared to the larger diameter classes. However, 

sugar maple is a shade-tolerant species that is noticeably absent from this list. Besides 

being shade-tolerant, American beech saplings may be present in large numbers as the 

result of root sprouts following harvesting and beech bark disease. Many of these young 

beech trees will eventually succumb to the disease before they have the opportunity 

to grow into the overstory, while occupying valuable growing space and inhibiting 

the regeneration and growth of more valuable species. In contrast, eastern hemlock, 

another shade-tolerant species, makes up a lower percentage of tree numbers in the 

sapling diameter classes when compared to the larger diameter trees. This indicates 

that hemlock is not regenerating as well as expected in the maturing forests of New 

Hampshire. Noncommercial species provide habitat diversity in the understory, but 

they can interfere with the reproduction of commercial species if they become too 

numerous. Striped maple now makes up 7 percent of trees in the 2-inch diameter 

class. Similarly, the dominance of beech in regenerating stands may be interfering with 

desirable species such as sugar maple (Hane 2003). Land managers should be aware of 

the potential for these species to cause problems in forest regeneration.

Eastern white pine and northern red oak are well represented in the large diameter 

classes, ranking first and second statewide in sawtimber volume in New Hampshire 

(Fig. 36). However, both generally continue to decrease as a percentage of total number 

of trees in all but the largest diameter classes (Fig. 46), so they are likely to be replaced 

by other species as the larger eastern white pine and northern red oak trees die or are 

harvested. Red maple and balsam fir represent large proportions of trees in medium-size 

diameter classes (4 to 14 inches for red maple and 2 to 8 inches for balsam fir). Those 

two species are positioned to increase in dominance in New Hampshire forests in future 

decades. Trends in volume show that since the 1960s, eastern hemlock and northern red 

oak have increased in the proportion of total volume they represent in New Hampshire, 

but increases in those species are likely to slow and reverse because they are not as well 

represented in the sapling-size class as they are in larger trees. If the current species 

composition remains constant as saplings mature, these data foretell a future forest 

overstory with more red maple, red spruce, and balsam fir trees and less eastern white 

pine, eastern hemlock, sugar maple, and northern red oak than today. Silvicultural 

efforts will need to be made to regenerate some species, particularly eastern white pine, 

eastern hemlock, and northern red oak. Long-term changes in forest composition 

will alter wildlife habitats and affect the value of the forest for timber products. Close 

examination of species composition changes in the future will be necessary to evaluate 

the potential impacts of climate change on individual species.
56 | FOREST FEATURES

0 

10 

20 

30 

40 

50 

60 

70 

White Pine Percentage

of Total Trees in Class

Diameter Class (inches)

(A)

0 

5 

10 

15 

20 

25 

Northern Red Oak Percentage

of Total Trees in Class

Diameter Class (inches)

(B)

■■ 2007

■■ 2012

■■ 2017

■■ 2007

■■ 2012

■■ 2017

2 4 6 8 10 12 14 16 18 20 21–29 >29 

2 4 6 8 10 12 14 16 18 20 21–29 >29 

Figure 46.—Percentage of the total number of trees on forest land that 

are (A) eastern white pine and (B) northern red oak by diameter class and 

inventory year, New Hampshire, 2017.
Ecosystem Indicators and 

Services

| 57

View of the White Mountains from the summit of Mount Washington. Photo by Randall Morin, USDA Forest Service.
58 | ECOSYSTEM INDICATORS AND SERVICES

Tree Crown Health and Damage

Background

The crown condition of trees is influenced by various biotic and abiotic stressors. Biotic 

stressors include native or introduced insects, diseases, invasive plant species, and 

animals. Abiotic stressors include drought, flooding, cold temperatures or freeze injury, 

nutrient deficiencies, the physical properties of soils that affect moisture and aeration, 

and toxic pollutants. New Hampshire forests have suffered from the impacts of wellknown exotic and invasive agents such as European gypsy moth (Lymantria dispar), 

hemlock woolly adelgid (Adelges tsugae), and the beech bark disease complex for many 

decades. A more recent invasion includes emerald ash borer (Agrilus planipennis).

Seasonal or prolonged drought periods have long been a significant and historical 

stressor in New Hampshire. Over the past 20 years, droughts have occurred in some 

regions during 1999, 2001, 2010, and 2016; conversely, some of the wettest years on 

record were 2006, 2009, and 2013 (Fig. 47) (National Centers for Environmental 

Information 2019). These extreme precipitation events can produce conditions that 

facilitate outbreaks of insects or disease (or both) and can be even more devastating to 

trees that are already stressed by pest damage or other agents. The risk of catastrophic 

economic and ecological loss of forest resources could increase due to forest maturity 

and more extreme weather-related events, including hurricanes, droughts, and floods 

caused by a changing climatic regime.

Tree-level crown dieback data are collected on P2+ plots. Crown dieback, defined as 

recent mortality of branches with fine twigs, reflects the severity of recent stresses on 

a tree. A crown is labeled as “poor” if crown dieback is more than 20 percent. This 

threshold is based on findings by Steinman (2000) that associate crown ratings with 

tree mortality. Additionally, crown dieback has been shown to be highly correlated 

with tree survival (Morin et al. 2015b).

Tree damage is assessed for all trees with a d.b.h. of 5.0 inches or greater. Up to three 

of the following types of damage can be recorded: insect damage, cankers, decay, fire, 

animal damage, weather, and logging damage. If more than three types of damage are 

observed, decisions about which three are recorded are based on the relative impact 

on the tree (USDA Forest Service 2016).

What we found

The incidence of poor crown condition is concentrated in southern New Hampshire 

(Fig. 48) and is particularly prevalent among ash species. The species with the highest 

proportion of live basal area containing poor crowns is white ash at 6 percent. 
ECOSYSTEM INDICATORS AND SERVICES | 59

-3 

-2 

0 

1 

2 

3 

4 

5 

6 

1895 1905 1915 1925 1935 1945 1955 1965 1975 1985 1995 2005 2015 

Palmer Z-Index 3-month Average

(June–August)

Year (June–August)

Figure 47.—Palmer Z-Index 3-month average (June–August), New Hampshire, by 

year. Recent dry years are shown in red, and recent wet years are shown in green.

Percentage of Basal 

Area with Poor Crowns

 ● 0

 ● 0–5

 ● 5–10

 ● >10

■ Forest

■ Nonforest

■ Water

Projection: New Hampshire State Plane, NAD83.

Sources: USDA Forest Service, Forest Inventory and Analysis program, 2017; NLCD 2006 (Fry et al. 2011).

Geographic base data are provided by the National Atlas of the USA®.

FIA data and Tools are available online at https://www.fia.fs.fed.us/tools-data/.

Cartography: R.S. Morin, USDA Forest Service, May 2019.

(A) (B)

Figure 48.—Percentage of live basal area with poor crowns for (A) all species and (B) ash 

species on inventory plots, New Hampshire, 2017. Depicted plot locations are approximate.
60 | ECOSYSTEM INDICATORS AND SERVICES

Conversely, other species have very low occurrence of poor crowns (Table 1). 

Additionally, the proportion of basal area with poor crowns has changed by less than 

2 percent for all species except white ash since 2012, and the proportion of basal area 

with poor crowns has dropped substantially for American beech since 2007 (Table 1).

Average crown dieback ranged from less than 1 percent for the important softwood 

species to 5 percent for paper birch (Table 2) and did not vary substantially over time 

for any species. The proportion of the trees that die increases with increasing crown 

dieback, except for the highest category of crown dieback. Fifteen percent of trees 

with crown dieback between 11 and 20 percent during the 2012 inventory were dead 

when visited again during the 2017 inventory (Fig. 49).

Damage was recorded on approximately 25 percent of the trees in New Hampshire, 

but there was considerable variation between species (Fig. 50). The most frequent 

damage recorded for all species was decay (present in 11 percent of trees), ranging 

from less than 4 percent on softwood species to 23 percent on American beech 

and red maple. Notably, cankers were present on 86 percent of American beech 

trees, 35 percent of white pine trees suffered branch or shoot damage from insects, 

and 17 percent of sugar maple trees showed signs of damage from bole borers. The 

high incidence of white pine damage is due to the accumulation of deformed stems 

caused by the native white pine weevil, Pissodes strobe, which typically causes stem 

deformities. The occurrence of all other injury types was below 10 percent.

Table 1.—Percentage of live basal area with poor crowns by inventory year, 

New Hampshire

Percentage of basal area with poor crowns

Species 2007 2012 2017

Balsam fir 5.2 0.0 1.0

Red spruce 9.7 0.0 0.3

Eastern white pine 0.3 1.0 0.4

Eastern hemlock 0.3 0.0 0.0

Red maple 7.8 2.9 3.2

Sugar maple 3.1 0.1 0.2

Yellow birch 2.2 0.0 0.8

Paper birch 5.4 3.1 3.4

American beech 6.2 4.1 2.6

White ash 1.2 2.7 6.2

Northern red oak 0.0 0.0 1.5
ECOSYSTEM INDICATORS AND SERVICES | 61

Table 2.—Mean crown dieback and other statistics for live trees (≥5 inches in diameter) on forest land 

by species, New Hampshire, 2017

Species

Trees 

sampled Mean SE Minimum Median Maximum

number ------------------------percent-----------------------

Paper birch 176 5.0 1.0 0 0 99

White ash 89 4.7 1.7 0 0 99

Red maple 468 3.4 0.4 0 0 99

Northern red oak 243 3.3 0.3 0 0 30

American beech 231 2.9 0.4 0 0 65

Sugar maple 225 1.6 0.2 0 0 20

Yellow birch 220 1.4 0.2 0 0 20

Eastern white pine 195 1.1 0.3 0 0 40

Balsam fir 274 0.5 0.2 0 0 45

Red spruce 238 0.4 0.3 0 0 65

Eastern white pine 318 0.4 0.1 0 0 15

■■ Mortality

■■ Survivor

75 

80 

85 

90 

95 

100 

0 1-10 11-20 >20

Frequency (percent)

Crown Dieback (percent)

Figure 49.—Crown dieback distribution by tree survivorship for 

remeasured trees, New Hampshire, 2012 to 2017.
 

0 20 40 60 80 100 

Red spruce 

Northern red oak 

Eastern hemlock 

Balsam fir 

White ash 

Yellow birch 

Paper birch 

Red maple 

Sugar maple 

Eastern white pine 

American beech 

All species 

Percentage of Trees 

■Animal 

■Logging/human 

■Cankers 

■ Other 

■Decay 

■ Weather 

■Insect damage 

■None 

What this means 

Ash is a minor component in most forests across New Hampshire, but it is important 

for biodiversity due to its value as a food source for many insect, bird, and small 

mammal species. Te mortality rate of white ash has increased in New Hampshire 

since 1997, but the rate is still low (Fig. 43). Te relatively unhealthy crowns of 

ash sampled may refect the impact of ash yellows (Morin and Lombard 2013). 

An additional concern for the health of ash trees is the emerald ash borer (EAB; 

Agrilus planipennis), which was discovered in southern New Hampshire in 2016 (see 

“Emerald Ash Borer” starting on p. 68). 

American beech contains a substantial volume of wood in New Hampshire and makes 

up a large component of seedlings and saplings in the understory. It is an important 

species due to its value to wildlife and as a pulpwood and frewood species. American 

beech mortality decreased slightly between the 2007 and 2017 inventories. The 

decrease in mortality and occurrence of poor crowns is likely to be related to the 

reduction in impacts from beech bark disease (BBD) as more stands move into the 

afermath phase of the disease (see “Beech Bark Disease” starting on p. 66). 

Decay is the most commonly observed damage, which is not unusual given that 

mature trees dominate most New Hampshire forests. Frequent tree damage (25 

percent of trees) and internal decay on 11 percent of trees in New Hampshire may 

be an indication of reduced tree health and timber quality. Te high frequency of 

cankers on American beech is due to the long history of BBD in the region. Although 

Figure 50.—Percentage of trees with damage, 

by species, New Hampshire, 2017. 

Species 

62 | ECOSYSTEM INDICATORS AND SERVICES 
ECOSYSTEM INDICATORS AND SERVICES | 63

weevil damage on white pine is common, it does not typically kill trees, but the form 

and quality of saw logs are impacted. Finally, the native sugar maple borer, Glycobius 

speciosus, is a common pest of sugar maple that is the likely cause of bole borer 

damage. Infestations can lead to lumber defect caused by discoloration, decay, and 

larval galleries and may make trees more susceptible to breakage during storms.

Down Woody Materials

Background

Down woody materials, in the various forms of fallen trees and shed branches, play a 

critical role in the forests of New Hampshire. Down woody materials provide valuable 

wildlife habitat, seedling browse protection, stand structural diversity, and a store of 

carbon and biomass. These materials also contribute to forest fire hazards via surface 

woody fuels.

What we found

The total carbon stored in down woody materials (fine and coarse woody debris 

and residue piles) on New Hampshire forest land exceeded 13 million tons in 2017, 

which is roughly equivalent to the 2010 estimate. Downed woody debris carbon 

was positively related to the amount of live tree basal area; forests with more than 

120 square feet per acre of basal area had the highest amounts of downed dead 

wood carbon (about 8.6 million tons) (Fig. 51). The downed dead wood biomass 

within New Hampshire forests is dominated by coarse woody debris (Fig. 52) at 

approximately 19 million tons with fine woody debris representing 31 percent of 

statewide totals. No piles of coarse woody debris (i.e., harvest residue piles) were 

sampled during this current inventory. The total volume of coarse woody debris in 

2017 was highest in the private ownership category, at approximately 1.6 billion cubic 

feet in New Hampshire forests (Fig. 53). The White Mountain National Forest had the 

second largest total volume of coarse woody debris (490 million cubic feet).
64 | ECOSYSTEM INDICATORS AND SERVICES

0

2,000,000

4,000,000

6,000,000

8,000,000

10,000,000

12,000,000

0–40 41–80 81–120 >120

Total Downed Dead Wood

Carbon (tons)

Basal Area (square feet per acre)

2010

2017

Figure 51.—Total carbon (short tons) and associated sampling errors in down 

woody materials (fine and coarse woody debris and piles) by live-tree basal area 

class on forest land, New Hampshire, 2006 to 2010 and 2012 to 2017. Error bars 

represent a 68 percent confidence interval around the mean.

Coarse Woody Debris

69%

Fine Woody Debris

31%

Figure 52.—Proportion of down woody material biomass by dead 

wood component (fine and coarse woody debris) on forest land, New 

Hampshire, 2017. No residue piles were sampled, 2012 to 2017.
ECOSYSTEM INDICATORS AND SERVICES | 65

0

200

400

600

800

1,000

1,200

1,400

1,600

1,800

2,000

National forest

Coarse Woody Debris Volume

(million cubic feet)

Ownership Group

State County and municipal Private

Figure 53.—Total volume and associated sampling error of coarse woody debris 

and dead wood piles on forest land by ownership group, New Hampshire, 2017. 

Error bars represent a 68 percent confidence interval around the mean.

What this means

Given the relatively moist temperate forests across New Hampshire, only in times of 

drought would the biomass of down woody materials be considered a fire hazard, 

especially as no residue piles were sampled during the current inventory. This stands 

in contrast to forests in southeastern states (Woodall et al. 2013), where industrial 

forest management is more widespread and rates of residue pile detection are 

higher. Although the carbon stocks associated with New Hampshire’s down woody 

materials are relatively small compared to those of soils and standing live biomass, 

these materials are still a critical component of the carbon cycle as a transitory stage 

between live biomass and other detrital pools such as the litter (Russell et al. 2015). 

Given that the vast majority of coarse woody debris volume was estimated to be in 

private ownership, it is the management of New Hampshire’s private forests that may 

affect the future of down woody material contributions to statewide forest carbon 

stocks and wildlife habitat (i.e., stand structure). Fuel loadings are estimated to be 

not excessively high across the state, so the numerous ecosystem services provided by 

down woody materials may outweigh possible fire dangers.

Tree Pests and Diseases of Special Concern

FOREST PESTS

Invasions by exotic diseases and insects are one of the most important threats to 

the productivity and stability of forest ecosystems around the world (Liebhold et 

al. 1995, Pimentel et al. 2000, Vitousek et al. 1996). Over the last century, forests of 
66 | ECOSYSTEM INDICATORS AND SERVICES

New Hampshire have suffered the effects of native insect pests such as forest tent 

caterpillar (Malacosoma disstria) and well-known exotic and invasive agents such 

as Dutch elm disease (Ophiostoma ulmi), chestnut blight (Cryphonectria parasitica), 

European gypsy moth (Lymantria dispar), and the beech bark disease complex. More 

recent invaders include hemlock woolly adelgid (Adelges tsugae) and emerald ash 

borer (Agrilus planipennis). Additionally, Asian longhorned beetle (Anoplophora 

glabripennis) is an impending threat that caused an extensive infestation in Worcester, 

MA in 2008.

BEECH BARK DISEASE

Background

American beech is a major component of the maple/beech/birch forest-type 

group, which makes up 52 percent of the forest resource in New Hampshire (Fig. 

4). American beech is an important pulpwood and firewood species and is also 

important for wildlife due to the hard mast that it produces. Beech bark disease 

(BBD) is an insect-fungus complex involving the beech scale insect (Cryptococcus 

fagisuga) and the exotic canker fungus Neonectria coccinea var. faginata or the native 

Neonectria galligena that kills or injures American beech. Three phases of BBD are 

generally recognized: 1) the advancing front, which corresponds to areas recently 

invaded by scale populations; 2) the killing front, which represents areas where 

fungal invasion has occurred (typically 3 to 5 years after the scale insects appear, but 

sometimes as long as 20 years) and tree mortality begins; and 3) the aftermath forests, 

which are areas where the disease is endemic (Houston 1994, Morin and Liebhold 

2015, Shigo 1972). The disease was inadvertently introduced via ornamental beech 

trees into North America at Halifax, Nova Scotia, in 1890 and then began spreading 

across New England. By 1975, all New Hampshire counties were infested.

What we found

Currently, the annual mortality rate for American beech is nearly double that of 

all trees in New Hampshire (1.2 percent), which is similar to the rate reported in 

previous inventories (Morin et al. 2011, 2015a). The impacts of BBD on mortality of 

large diameter beech have steadily skewed the diameter distribution of beech toward 

smaller trees since 1983 (Fig. 54). The number of beech seedlings per acre increased 

slightly between 2007 and 2012 and has since remained stable.
ECOSYSTEM INDICATORS AND SERVICES | 67

1983

1997

2007

2012

2017

0 

2 

4 

6 

8 

10 

12 

14 

16 

2 4 6 8 10 12 14 16 18 20 21–29 >29 

Percentage of All Trees

Diameter Class 

Figure 54.—Proportion of all trees on timberland that are American 

beech, by diameter class and inventory year, New Hampshire.

What this means

New Hampshire has been infested by BBD for over 40 years, so forests are largely in 

the aftermath phase of BBD. Aftermath forests are often characterized by a dearth of 

large beech trees due to past BBD-induced mortality, which is associated with large 

numbers of beech seedlings and saplings. This condition, often referred to as “beech 

brush,” can interfere with regeneration of other hardwood species such as sugar 

maple (Hane 2003). Beech brush includes trees with low vigor and slow growth that 

often succumb to the disease before making it into the overstory. These trees are also 

unlikely to reach sawtimber size or produce mast, which is important for wildlife.

HEMLOCK WOOLLY ADELGID

Background

Eastern hemlock is a major component of the forest resources in New Hampshire. 

Due to its high value as a timber species, the wildlife habitat it provides, and the 

unique niche it fills in riparian areas, it is an ecologically important species. Hemlock 

woolly adelgid (HWA) is native to East Asia and was first noticed in the eastern 
68 | ECOSYSTEM INDICATORS AND SERVICES

United States in the 1950s (Ward et al. 2004). Since then, it has slowly expanded its 

range. In areas where HWA has established, populations often reach high densities, 

causing widespread defoliation and sometimes mortality of eastern hemlock 

(McClure et al. 2001, Morin and Liebhold 2015, Orwig et al. 2002).

What we found

Hemlock woolly adelgid was first observed in Rockingham County, New Hampshire 

in 2001. By 2012, the insect had been discovered in seven counties in southern New 

Hampshire. Forests with the highest proportion of hemlock volume are located in 

southern New Hampshire (Fig. 34). Unlike many other states that have been impacted 

by HWA, there has been no significant change in hemlock annual mortality rate 

(Fig. 44), crown health (Tables 1, 2), or incidence of insect damage (Fig. 50) in New 

Hampshire. Additional analyses revealed no differences in the mortality rate and 

crown health of hemlock between infested and uninfested counties. 

What this means

Hemlock woolly adelgid has already spread into some of the counties of New 

Hampshire where hemlock is the most abundant. Morin et al. (2009) estimate 

that HWA is spreading to the north at a rate of between 9 and 10.6 miles per year. 

However, cold winter temperatures can cause considerable adelgid mortality and 

trigger dramatic population declines (Skinner et al. 2003). Therefore, the rate of 

spread of HWA into the rest of New Hampshire may be influenced by temperature. 

Although the health of eastern hemlock in the forests of New Hampshire does not 

appear to have been impacted by HWA yet, it is important to continue monitoring 

crown health and mortality over the coming decade. A previous study reported that 

hemlock mortality increases were not substantial until HWA had infested counties 

for more than 20 years (Morin and Liebhold 2015), suggesting impacts in New 

Hampshire will not be apparent for another 5 to 10 years.

EMERALD ASH BORER

Background

Emerald ash borer (EAB), a wood-boring beetle native to Asia, was first detected 

in North America in 2002, where it was found near Detroit, MI (Herms and 

McCullough 2014). As EAB is difficult to detect at low levels, natural spread was 

exacerbated by human-mediated transportation of infested materials; spread of EAB 

has outpaced detection, with population establishment averaging 3 to 8 years prior 
ECOSYSTEM INDICATORS AND SERVICES | 69

to identification (Herms and McCullough 2014). This beetle has been present in 

New Hampshire since 2013, when it was detected in Merrimack County. All North 

American ash are hosts of EAB. Although EAB shows some preference for stressed 

trees, all trees 1 inch in diameter or greater are susceptible regardless of vigor (Herms 

and McCullough 2014). Mortality due to EAB varies by infestation level, but a 

mortality-to-gross-growth ratio above 0.6 is indicative of an acute forest health issue 

(Conkling et al. 2005).

What we found

There are an estimated 89.4 million ash trees (d.b.h. of 1 inch or greater), or 2 percent 

of total species abundance on forest land. White ash is the most prevalent ash species 

(93 percent of total ash abundance), followed by black ash (6 percent) and green ash 

(less than 1 percent). Ash is present on 1.4 million acres, or 30 percent of forest land, 

but it generally makes up less than 25 percent of total live-tree basal area. Average 

annual mortality of ash on forest land slightly decreased from 4.0 million cubic feet 

in 2012 to 3.4 million cubic feet in 2017; ash mortality represented 3 percent of total 

mortality in 2017. Between 2012 and 2017, the mortality-to-gross-growth ratio for 

ash decreased from 0.48 to 0.44 (Fig. 55).

0.0 0.6 1.2 1.8

Other eastern soft hardwoods

Eastern noncommercial hardwoods

Cottonwood and aspen

Beech

Soft maple

Ash

Yellow birch

Spruce and balsam fir

Eastern white and red pine

Eastern hemlock

Mortality-to-Growth Ratio

■■ 2012

■■ 2017

2.4

Species Group

Figure 55.—Ratio of average annual mortality volume to gross growth 

volume for selected species groups on forest land by inventory year, 

New Hampshire. Error bars represent a 68 percent confidence interval 

around the mean. Vertical line shows the threshold indicating an acute 

health issue (Conkling et al. 2005).
70 | ECOSYSTEM INDICATORS AND SERVICES

What this means

Ash is an important component of New Hampshire’s woodland, riparian, and urban 

forest resource. Currently, the ash resource is stable. However, EAB has caused 

extensive ash mortality throughout the eastern United States and therefore represents 

a significant threat to the ash resource in New Hampshire. Mortality of ash is 

expected to increase as EAB persists and populations grow. The loss of ash in forested 

ecosystems will affect species composition and alter community dynamics. Continued 

monitoring will help to identify the long-term impacts of EAB in forested settings. 

Regeneration Status

Background

Trajectories for long-term sustainability of forest values are set in the forest 

understory during the stand-initiation phase of development, which makes 

regeneration management a key factor for sustaining healthy and productive forests 

(Smith et al. 1997). The Wildlife Society recently issued a policy statement for 

managing forest biodiversity in the northeastern United States that addresses two 

tenets of sustainable restoration management (Ronis 2018):

• “Sustainable forest management strategies can promote a mosaic of forest structure 

and age-classes across a landscape and create various habitat types, which 

contribute to the maintenance of biological diversity.”

• “In the northeastern United States, land use changes, such as natural succession 

and development, have created an underrepresentation of both early- and latesuccessional habitat, and a predominance of secondary growth (40-100 year-old 

forests) across the region.”

Forest restoration management and policy aimed at “young forest” (seedlings up to 

trees 20 years old) are critically important, but are complicated by multiple stressors 

and their interactions, such as a changing climate, invasive plants, herbivory, and 

wildfire exclusion.

In 2012, the Forest Service’s Northern Research Station (NRS) FIA implemented a 

set of regeneration indicator (RI) measurement protocols on a subset of NRS-FIA 

core sample plots (Phase 2, or P2) measured during the growing season (Phase 2+) 

to identify contemporary challenges for managers and policymakers (McWilliams 

et al. 2015). The results in this report are based on measurements of 94 sample plots 

measured from 2013 through 2017. The procedures measure all established tree 

seedlings at least 2 inches tall by height class and include a browse impact assessment 
ECOSYSTEM INDICATORS AND SERVICES | 71

for the surrounding area. The measurements of small seedlings supplement FIA’s 

P2 seedling estimates, which are limited to hardwood stems at least 1 foot long and 

softwood stems at least 6 inches long.

What we found

The 0- to 20-year stand-age class is FIA’s primary indicator for young forest extent, 

condition, and health. Currently, only 4.9 percent of New Hampshire forest land is 

20 years or younger. The four most extensive forest-type groups, which make up 85 

percent of the total forest land in New Hampshire, all have low amounts of young 

forest (Table 3), with percentages ranging from 0 for oak/hickory (no samples found) 

to 7.7 for spruce/fir. Young forest has become so rare that the P2 sample results in 

high sampling errors.

Table 3.—Summary of young foresta resource for the most prevalent forest-type groups, New 

Hampshire, 2017

Forest-type group Forest land Young forest Young forest

Young forest 

confidence intervalb 

percent percent acres acres

Maple/beech/birch 51.9 4 97,189 22,956 

White/red/jack pine 11.6 1 7,949 5,943 

Oak/hickory 10.8 0 N/A N/A 

Spruce/fir 9.8 8 35,951 14,158 

a Young forest is defined here as the area of forest land in the 0- to 20-year age class.

b Confidence intervals based on 68 percent sampling errors.

The impacts of large ungulate browsing of young tree seedlings are a large 

impediment to establishing viable forest regeneration (Russell et al. 2001). Where 

forest land has at least moderate browse impacts, managers should consider whether 

to include ameliorative treatments in their regeneration management prescriptions 

(Brose et al. 2008). Just over half the samples had at least moderate impacts and are 

spread evenly across the New Hampshire forest landscape (Fig. 56).

The RI estimate of the number of established seedlings at least 2 inches tall is 28.6 

billion, or 5,579 per acre. Comparing tree-seedling composition (taxa) and abundance 

(numbers of stems) by size class with total aboveground biomass (AGB) for dominant 

and codominant adults sheds light on trends in recruitment (Fig. 57). Although high 

sampling errors make it difficult to make precise inferences, some broad directions 

are apparent. Prospective “gainers” are taxa with comparatively high percentages of 

stems in the reproduction pool. Balsam fir and American beech are posting high 

percentages across all seedling size-classes. Red maple, sugar maple, and red spruce
72 | ECOSYSTEM INDICATORS AND SERVICES

Browse Impact Level

● Low

● Moderate

● High

Figure 56.—Browse impact level based on Forest Inventory 

and Analysis forested Phase 2+ sample plots, New Hampshire, 

2013 to 2017. Depicted plot locations are approximate. 

2

2

2

4

5

7

8

10

21

29

0 5 10 15 20 25 30 35

Percentage of Seedlings 

2 to 11 .9 Inches Tall

Red maple

Sugar maple

American beech

Balsam fir

Striped maple

Eastern white pine

White ash

Northern red oak

Eastern hemlock

Red spruce 3

3

4

5

6

10

10

12

13

American beech 22

Balsam fir

Sugar maple

Red maple

Striped maple

Red spruce

White ash

Yellow birch

Eastern white pine

Paper birch

0 5 10 15 20 25 30

Percentage of Seedlings 

1 .0 to 4 .9 Feet Tall

2

4

5

5

6

6

9

12

16

American beech 22

Balsam fir

Red maple

Striped maple

Red spruce

Paper birch

Eastern hemlock

Sugar maple

Yellow birch

White ash

0 5 10 15 20 25 30

Percentage of Seedlings 

5 Feet Tall and Greater

4

4

5

5

6

7

10

15

16

Northern red oak 17

Red maple

Eastern white pine

Sugar maple

Yellow birch

Eastern hemlock

American beech

Paper birch

White ash

Red spruce

0 5 10 15 20 25 30

Percentage of Dominant 

and Codominant Adult Trees

(A) (B)

(C) (D)

Figure 57.—(A–C) Numbers of seedlings based on Forest Inventory and Analysis forested Phase 2+ sample 

plots by height class for the 10 most abundant species in each class, and (D) number of dominant and 

codominant adult trees for the 10 species using Phase 2 sample plots, New Hampshire, 2017.
ECOSYSTEM INDICATORS AND SERVICES | 73

are poised to continue as canopy dominants. At this time, eastern white pine emerges 

as a “loser” among regenerating species because it shows relative seedling abundance 

far below its AGB coverage of 15 percent. Findings for northern red oak also indicate 

underrepresentation in the seedling component.

What this means

As forests continue to mature, the rich array of goods, services, and wildlife habitat 

available from young forest is missing in some areas of New Hampshire. Stand age 

was not recorded in the earliest FIA report (USDA Forest Service 1954); however, the 

small diameter stand-size class for timberland is a rough surrogate for the 0- to 20-

year age class because it represents conditions dominated by seedlings and saplings. 

In 1948, 24 percent of the timberland area was classified as small diameter stands, 

compared with 11 percent in 2017. Over the same period, large diameter stands 

increased from 39 percent to 64 percent of timberland. The current distribution of 

forest land by stand-size and stand-age class exhibits a deficit in young forest that has 

ramifications for sustainability, particularly for wildlife species that depend on earlysuccessional forest for part or all of their life cycle. 

The RI seedling inventory results suggest potential shifts in composition of canopy 

adults. Northern red oak is currently among the most abundant species in New 

Hampshire, but its reproduction pool is too low to maintain this role in the future. It 

is likely to be replaced by red maple as the most dominant species in coming decades. 

Positive results for balsam fir and red spruce seedlings indicate that young stands 

preferred symbiotically by snowshoe hare (Lepus americanus) and Canada lynx (Lynx 

canadensis) are being established (Litvaitis 1985). American beech may be expected 

to become a future dominant, but beech bark disease and the viability of root sprouts 

leave this issue unresolved and something to watch in future inventories. The signal 

that eastern white pine has a low reproduction pool tells us that species-specific stand 

management is needed across the different associations within which it occurs, from 

mixed to pure. 

The ecological implications of browsing are expected to have severe long-term 

impacts on forest composition, structure, and function (Côté et al. 2004, Russell 

et al. 2001). The results of the browse evaluation confirm that forest regeneration 

management will need to consider local browse conditions during the stand-initiation 

phase across much of New Hampshire. 

New Hampshire forests face a variety of forest health risks, and establishing desired 

tree seedlings is an integral step in addressing most of them during the early phases of 

forest development. The interactions of factors such as browsing and invasive species 
74 | ECOSYSTEM INDICATORS AND SERVICES

make it more difficult to establish forests, particularly oaks. These conditions do not 

preclude regeneration of the oak/hickory forests because management techniques 

to develop young oak/hickory forests have proven successful (Dey 2014). The future 

of young forest and related resources will depend on the number of stand-initiation 

disturbances and the frequency of planned regeneration harvests and restoration 

versus unplanned major disturbances, such as catastrophic mortality or wind throw.

Invasive Plant Species

Background

Invasive plant species (IPS) are a concern throughout the world. Some invasive plants 

are alternate hosts for insects and diseases and can cause severe agricultural impacts. 

The presence of IPS also affects forest structure, health, and diversity. These invaders 

often form very dense colonies that limit availability of light, nutrients, and water. 

While some invasive plants have beneficial characteristics, such as for medicinal 

purposes (e.g., common barberry) (Kurtz 2013) or culinary use (e.g., garlic mustard), 

the negative impacts to ecosystems are problematic. Annually, nonnative IPS cost 

billions of dollars through monitoring and removal. Because of the vast implications 

of IPS, it is important to increase awareness through informing and educating private 

landowners and the rest of the public.

What we found

During the 2017 inventory, 111 P2 invasive plots in New Hampshire were monitored 

for the presence of 39 IPS and one undifferentiated genus (nonnative bush 

honeysuckle) (Table 4) as a part of the invasive plant monitoring protocol. Invasive 

plant species were present on 13 plots (11.7 percent). This result is similar to what was 

found in 2012, when 11.2 percent of plots had one or more IPS present.

Eight of the monitored IPS were observed. The most commonly observed invasive plant 

was Oriental bittersweet (7 plots; 6.3 percent), closely followed by glossy buckthorn 

(Fig. 58, Table 5). Oriental bittersweet was found on a higher percentage of plots than in 

2012, when 2.6 percent of plots contained this species (Morin et al. 2015a). 

In New Hampshire, most plots did not have invasive plants, but one plot had six 

invasive plants (Fig. 59). The majority of plots with IPS are in the southern part of the 

State; few northern plots contained monitored invasive plants. New Hampshire has 

about half as many plots with IPS as neighboring Vermont.
ECOSYSTEM INDICATORS AND SERVICES | 75

Table 4.—The 39 invasive plant species and 1 undifferentiated genus monitored by the Northern Research 

Station on Forest Inventory and Analysis Phase 2 invasive plots, 2007 to present

Tree Species Vine Species

black locust (Robinia pseudoacacia) English ivy (Hedera helix)

chinaberry (Melia azedarach) Japanese honeysuckle (Lonicera japonica)

Norway maple (Acer platanoides) Oriental bittersweet (Celastrus orbiculatus)

princesstree (Paulownia tomentosa)

punktree (Melaleuca quinquenervia) Herbaceous Species

Russian olive (Elaeagnus angustifolia) black swallow-wort (Cynanchum louiseae)

saltcedar (Tamarix ramosissima) bull thistle (Cirsium vulgare)

Siberian elm (Ulmus pumila) Canada thistle (Cirsium arvense)

silktree (Albizia julibrissin) creeping jenny (Lysimachia nummularia)

tallow tree (Triadica sebifera) dames rocket (Hesperis matronalis)

tree of heaven (Ailanthus altissima) European swallow-wort (Cynanchum rossicum)

garlic mustard (Alliaria petiolata)

Woody Species giant knotweed (Polygonum sachalinense)

autumn olive (Elaeagnus umbellata) Japanese knotweed (Polygonum cuspidatum)

common barberry (Berberis vulgaris) leafy spurge (Euphorbia esula)

common buckthorn (Rhamnus cathartica) Bohemian knotweed (Polygonum xbohemicum)

European cranberrybush (Viburnum opulus) purple loosestrife (Lythrum salicaria)

European privet (Ligustrum vulgare) spotted knapweed (Centaurea stoebe ssp. micranthos)

glossy buckthorn (Frangula alnus)

Japanese barberry (Berberis thunbergii) Grass Species

Japanese meadowsweet (Spiraea japonica) common reed (Phragmites australis)

multiflora rose (Rosa multiflora) Nepalese browntop (Microstegium vimineum)

nonnative bush honeysuckle (Lonicera spp.) reed canarygrass (Phalaris arundinacea)

Table 5.—Invasive plant species observed on Forest 

Inventory and Analysis Phase 2 invasive plots, and 

frequency of observation, New Hampshire, 2017

Percentage of plots

Oriental bittersweet 6.3

Glossy buckthorn 5.4

Japanese barberry 4.5

Nonnative bush honeysuckle 3.6

Multiflora rose 2.7

Autumn olive 1.8

Norway maple 1.8

Common buckthorn 1.8
76 | ECOSYSTEM INDICATORS AND SERVICES

Invasive Plant Species

 ● Oriental bittersweet

 ● Glossy buckthorn

■ Forest

■ Nonforest

Projection: New Hampshire State Plane, NAD83.

Source: ESRI data and maps, 2008.

FIA data and Tools are available online at 

https://www.fia.fs.fed.us/tools-data.

Cartography: C.M. Kurtz, USDA Forest Service, November 2019.

Figure 58.—Distribution of the two most common 

invasive plant species observed on Forest 

Inventory and Analysis Phase 2 invasive plots, New 

Hampshire, 2017. Depicted plot locations 

are approximate.

Number of IPS per Plot

● 0

● 1

● 2

● 3

● 4

● 6

■ Forest

■ Nonforest

Projection: New Hampshire State Plane, NAD83.

Source: ESRI data and maps, 2008.

FIA data and Tools are available online at 

https://www.fia.fs.fed.us/tools-data.

Cartography: C.M. Kurtz, USDA Forest Service, November 2019.

Figure 59.—Number of invasive plant species (IPS) 

observed on Forest Inventory and Analysis Phase 2 

invasive plots, New Hampshire, 2017. Depicted plot 

locations are approximate.

What this means

Since the last survey in 2012, there has been little change in the percentage of plots 

invaded or the number of plots containing each IPS. It will be important to continue 

to watch how these species spread and whether new IPS are observed. Invasive plants 

are a concern because they can cause detrimental forest changes. These plants can 

alter hydrology, displace native species, and reduce the aesthetic appeal of an area. 

Heavily infested areas may result in a change in wildlife habitat. Once established, IPS 

can rapidly increase in cover and impact co-occurring native plant species. Through 

continual monitoring of invasive species, managers will be aware of the presence of 

these aggressive species and be able to make better informed management decisions.
ECOSYSTEM INDICATORS AND SERVICES | 77

Forest Habitats

Background

New Hampshire forests provide habitat for numerous species of mammals, birds, 

reptiles, and amphibians, as well as for fish, invertebrates, and plants. Several 

indicators of wildlife habitat abundance can be derived from FIA data. Forest 

composition and structure affect the suitability of habitat for each species. According 

to the 2015 New Hampshire Wildlife Action Plan (New Hampshire Fish and Game 

Department [NH FGD] 2015), forest habitat types at highest risk from the effects 

of natural system modifications include floodplain forest, lowland spruce-fir forest, 

and shrublands, while hemlock-hardwood-pine forest and pine barrens were ranked 

with a medium threat score. Lowland spruce-fir forests, for example, provide habitat 

for over 100 species of vertebrates, including black bear (Ursus americanus), hoary 

bat (Lasiurus cinereus), Canada lynx, American three-toed woodpecker (Picoides 

dorsalis), and American marten (Martes americana), and provide deer (Odocoileus

spp.) yards during heavy snow years (NH FGD 2015). Shrublands and other woody 

early-successional habitats are declining in New Hampshire and throughout the 

Northeast, posing threats to associated wildlife species such as golden-winged warbler 

(Vermivora chrysoptera), New England cottontail (Sylvilagus transitionales), American 

woodcock (Scolopax minor), ruffed grouse (Bonasas umbellus), smooth green snake 

(Opheodrys vernalis), wood turtle (Glyptemys insculpta), and the black racer (Coluber 

constrictor priapus) (NH FGD 2015). Abundance and trends in forest structure and 

successional stages serve as indicators of population carrying capacity for wildlife 

species (Hunter et al. 2001).

What we found

Area of timberland in New Hampshire decreased slightly between 1983 and 2017, 

from 4.8 million acres to 4.5 million acres. During that time, the proportion of 

timberland in the small diameter stand-size class decreased from 11 percent to 9 

percent, then returned to 11 percent, while distribution of medium diameter forest 

decreased from 37 percent to 24 percent, and large diameter forest increased steadily 

from 52 percent to 65 percent of total timberland area (Fig. 60).

A large majority of New Hampshire forest land (82 percent) is in stand-age classes 

between 40 and 100 years. About 8 percent is over 100 years of age. Small diameter 

stand-size classes predominate in forests of 0 to 40 years, and large diameter 

predominates in forests over 60 years of age; forests of 41 to 60 years contain almost 

equally large acreages of medium and large diameter stand-size classes (Fig. 61).
78 | ECOSYSTEM INDICATORS AND SERVICES

0

1

2

3

4

5

6

1983

1997

 2007

2012

2017

Timberland Area (million acres)

Inventory Year

0

10

20

30

40

50

60

70

80

90

100

Percentage of Timberland Area

1983

1997

2007

2012

2017

Inventory Year

■Large diameter

■ Medium diameter

■Small diameter

(A) (B)

■Large diameter

■ Medium diameter

■Small diameter

Figure 60.—(A) Area and (B) percentage of timberland by 

inventory year and stand-size class, New Hampshire.

0

200

400

600

800

1,000

1,200

1,400

1,600

0–20 21–40 41–60 61–80 81–100 >100

Forest Land Area (thousand acres)

Stand Age (years)

■Large diameter

■ Medium diameter

■Small diameter

Figure 61.—Area of forest land by stand-age class and stand-size class, 

New Hampshire, 2017.
ECOSYSTEM INDICATORS AND SERVICES | 79

What this means

Decreasing abundance of medium diameter stand-size classes is offset by increasing 

abundance in the large diameter size classes. However, the great majority of stands 

in the large diameter class (89 percent) are less than 100 years of age. Although both 

stand-size class and stand-age class provide indicators of forest successional and 

structural stage, the two attributes are not exactly interchangeable and are best viewed 

in combination. 

The New Hampshire Wildlife Action Plan states: “Many shrublands will naturally 

succeed into forests and therefore, natural disturbances or specific management 

practices should be allowed to occur to sustain this habitat” (NH FGD 2015). In 

contrast, “some conservation strategies for lowland spruce-fir forests are to protect 

unfragmented blocks of land and to maintain late successional habitat” (NH FGD 

2015). These approaches reflect the need to monitor and maintain forest conditions in 

multiple forest type, size, and age classes, including both early (young) and late (old) 

successional stages to provide habitats for all forest-associated species.

Standing Dead Trees

Background

Snags provide areas for foraging, nesting, roosting, hunting perches, and cavity 

excavation for wildlife, from primary colonizers such as insects, bacteria, and fungi 

to birds, mammals, and reptiles. Stands with numerous snags provide more food and 

potential nests for species like American three-toed woodpecker, and the majority of 

northern long-eared bats (Myotis septentrionalis) roost in snags (NH FGD 2015). The 

number and density of standing dead trees (5 inches or greater d.b.h.), together with 

decay classes, species, and sizes, define the snag resource across New Hampshire forests.

What we found

There are over 132 million standing dead trees on the 4.7 million acres of forest 

in New Hampshire. This represents an overall density of 28 standing dead trees 

per acre of forest land, ranging from 21 per acre on private lands to 56 per acre on 

national forest lands. Species groups with the largest percentages of standing dead 

trees include other eastern soft hardwoods (32 percent), other eastern softwoods (23 

percent), eastern noncommercial hardwoods (22 percent), and eastern white and red 

pine (19 percent). Other red oaks, select red oaks, and eastern hemlock had the lowest 

percentages (less than 5 percent) (Fig. 62).
80 | ECOSYSTEM INDICATORS AND SERVICES

Across New Hampshire, more than 83 percent of standing dead trees were smaller 

than 11 inches d.b.h. The greatest number of standing dead trees (89 percent) was 

estimated for the three intermediate decay classes, with the fewest (1 percent) in the 

class of most decay (Fig. 63).

0 5 10 15 20 25 30 35

Percentage of Standing Dead Trees

Other eastern soft hardwoods

Other eastern softwoods

Eastern noncommercial hardwoods

Eastern white and red pine

Spruce and balsam fir

Cottonwood and aspen

Other yellow pines

Ash

Yellow birch

Select white oaks

Beech

Soft maple

Basswood

Hard maple

Other eastern hard hardwoods

Other red oaks

Select red oaks

Eastern hemlock

Species Group

Figure 62.—Percentage of standing dead trees by 

species or species group, New Hampshire, 2017.

■■ No evidence of branches remains

■■ Few or no limb stubs remain

■■ Only limb stubs present

■■ Few limbs and no fine branches present

■■ All limbs and branches present

0 5 10 15 20 25

Diameter Class (inches)

Number of Standing Dead Trees (millions)

29.0+

21.0–28.9

19.0–20.9

17.0–18.9

15.0–16.9

13.0–14.9

11.0–12.9

9.0–10.9

7.0–8.9

5.0–6.9

Figure 63.—Distribution of standing dead trees by decay and 

diameter classes for all dead trees, New Hampshire, 2017.
ECOSYSTEM INDICATORS AND SERVICES | 81

What this means

Snags result from a variety of potential causes, including diseases and insects, weather 

damage, fire, flooding, drought, and competition. The spruce and balsam fir species 

group contained the greatest total number of standing dead trees (over 36 million), 

but rankings varied when the percentage of standing dead trees was assessed within 

each species group. Snags provide habitat for many vertebrate and invertebrate 

life forms. Most cavity nesting birds are insectivores, which help to control insect 

populations. Providing a variety of forest structural stages and retaining specific 

features like snags on both private and public lands are ways that forest managers 

maintain the abundance and quality of habitat for forest-associated wildlife species in 

New Hampshire. 

Urbanization and Fragmentation of Forest Land

Background

The wildland-urban interface (WUI) is the zone where human development meets or 

intermingles with undeveloped wildland vegetation, and it is the fastest-growing land 

use type in the conterminous United States (Mockrin et al. 2019, Radeloff et al. 2017). 

Although originally defined to identify the area where wildfires pose the greatest risk 

to people, the WUI is associated with a variety of consequential human-environment 

conflicts. These include impacts such as the loss and fragmentation of native species, 

the introduction and spread of nonnative species (e.g., Gavier-Pizarro et al. 2010, 

Riitters et al. 2018), the loss of habitat area or critical connectivity (e.g., Bregman et al. 

2014, Rogers et al. 2016), increased mortality of wildlife (e.g., Klem 2009, Loss et al. 

2013), reductions in regional complexity of plant and animal communities (e.g., 

Ferguson et al. 2017, Mack et al. 2000), increases in nonnative insect and disease 

invasions (e.g., Guo et al. 2018), and impacts on water quality and quantity from 

impervious surfaces and increased pollution (e.g., Bar-Massada et al. 2014, GonzalezAbraham et al. 2007). The 2018 report from the New England Climate Change 

Response Framework on New England and New York forest ecosystem vulnerability 

(Janowiak et al. 2018) identified fragmentation and land use change as among 

the six current greatest stressors and threats to forest ecosystems. In turn, forest 

fragmentation and urbanization heavily influence two of the other major threats: 

invasion by nonnative species, and forest diseases and insect pests. 

In previous reports in several areas we summarized forest spatial integrity using 

a spatial integrity index that combined forest patch size, local forest density, and 

connectedness to core forest land; included maps of the pervasiveness of roads 
Status of the Wildland-Urban Interface 

■16–127 houses per square mile 

■128–1,919 houses per square mile 

■>1,919 houses per square mile 

WUI since 1990

or before 

 

■

82 |

throughout forested areas; and introduced the additional and extensive efect that 

2010 levels of housing density had on forest land (e.g., Widmann et al. 2015). 

With the recent completion of a temporally consistent census block-level dataset 

capable of accurately comparing block-level change in housing densities between 

1990 and 2010 (Mockrin et al. 2019, Radelof et al. 2017), we are now able to analyze 

changes in house density and forest land at a fner spatial resolution and with more 

accuracy than previously possible. We have used these data here to identify FIA 

forest land and changes in WUI levels of house density via the following categories: 

forest land in census blocks that have had house densities above established WUI 

thresholds for 30 years or more (from 1990 or before), forest that frst reached WUI 

house density levels in the 1990s, forest that frst reached WUI house density levels in 

the 2000s, forest that underwent change in WUI house density in both decades, and 

forest land that remained in non-WUI census blocks in 2010 (Fig. 64). In Figure 64 

forest land is depicted in the map using the 2011 National Land Cover Dataset (Jin et 

al. 2013) to mask out nonforest areas; however, all forest land statistics reported are 

summarized from the FIA plot data. 

■Still non-WUI in 2010 

■Became WUI in the 1990s 

■Became WUI in the 2000s 

■Change in both decades 

■Decrease in WUI intensity 

■Reverting to non-WUI 

Nonforest 

Figure 64.—Map of forest cover by census block-level change in wildlandurban interface (WUI) status between 1990 and 2010, New Hampshire. 

82 | ECOSYSTEM INDICATORS AND SERVICES 
ECOSYSTEM INDICATORS AND SERVICES | 83

We examined 1) how much forest land is changing or is at risk of change because 

of its proximity to WUI levels of housing development, 2) the rate of change 

between 1990 and 2010, 3) the extent to which WUI house densities occur in forest 

land that might otherwise be considered high integrity or core forest land, and 4) 

whether differences in forest type, ownership, and stand size have been affected by 

urbanization levels above the low (16 to 127 houses per square mile), medium (128 

to 1,919), and high (>1,919) WUI housing density thresholds (hereafter referred to 

collectively as WUI).

What we found

Both the area and proportion of New Hampshire forest that is non-WUI continued 

to shrink, from 3.4 million acres to 3.0 million acres (72 percent to 62 percent of 

the total forest land) between 1990 and 2010 (Fig. 65). By 2020, 1.3 million acres of 

New Hampshire forest land will have been in WUI conditions for at least 30 years. 

Urbanization of forest land occurred in some areas at higher rates during the 1990s, 

and in others, during the 2000s. For still other areas, the rate of forest urbanization 

was somewhat constant throughout both decades. Most counties experienced 

additional urbanization at rates greater than 5 percentage points per decade (Fig. 66). 

Percentage of Forest Land 

Not Located in the 

Wildland-Urban Interface

■≤10

■>10–25

■>25–50

■>50–75

■>75–100

(A) 1990 (B) 2010

Figure 65.—Proportion of forest not located in the wildland-urban interface in (A) 1990 and (B) 2010.
84 | ECOSYSTEM INDICATORS AND SERVICES

Proportion of Forest

<= 2

< 2 - 5

< 5 - 10

< 10 - 20

< 20 - 40

Percentage of Forest Land

■<2

■2–5

■>5–10

■>10–20

■>20–40

Projection: New Hampshire State Plane, NAD83. Sources: USDA Forest Service,

Forest Inventory and Analysis program, 2008; Wildland-urban interface 2010 (Radeloff et al. 2017).

Geographic base data are provided by the National Atlas of the USA®.

Cartography: R. Riemann, USDA Forest Service, June 2019.

Figure 66.—Proportion of forest land in each county that 

changed from non-wildland-urban interface (non-WUI) 

conditions to WUI conditions, New Hampshire, 1990 to 2010.

Urbanization affected forest types to differing degrees by 2010, from 5 percent of 

the forest area for paper birch and red spruce forest types to 73 percent of the forest 

area for white oak/red oak/hickory and eastern white pine/northern red oak/white 

ash forest-type groups) (Table 6). Three additional forest types or forest-type groups 

had 50 percent or more of their area in WUI as of 2010 (eastern white pine/eastern 

hemlock, eastern white pine, and hard maple/basswood). The eastern white pine/

northern red oak/white ash, hard maple/basswood, and white oak/red oak/hickory 

forest-type groups had the greatest proportion of their area converted to WUI 

between 1990 and 2010, at 17 to 19 percent. Seven forest types had 10 percent or more 

of their forest area converted to WUI during that time (Table 6). Four forest types 

are being disproportionately affected by WUI development. For example, 14 percent 

of the total forest area in WUI in New Hampshire in 1990 was in the eastern white 

pine forest type, which itself represents only 8 percent of the total forest area in New 

Hampshire. Conversely, the sugar maple/beech/yellow birch forest-type group was 

affected by WUI to a much lower degree (33 percent) than its proportion of the total 

forest area in New Hampshire (44 percent) (Table 7). 
ECOSYSTEM INDICATORS AND SERVICES | 85

Table 6.—Summary of wildland-urban interface (WUI) change groups by forest type or forest-type group, 

New Hampshire (percentages may not add to 100 because of rounding)

WUI change group

Forest type or 

forest-type group

Total 

acres

All 

classes

WUI 

since 

1990 or 

earlier

New 

WUI 

1990–

2010

Still 

non-WUI 

as of 

2010

Potential 

WUI 

decrease

Proportion 

of area 

in WUI in 

2010

Total area (acres) 

or percentage

4,783,480 100 28 9 62 1 73

percent ---------------------------percent---------------------------

White oak/red oak/

hickory

194,118 4 56 17 25 2 73

Eastern white pine/

northern red oak/

white ash

297,759 6 53 19 25 2 73

Eastern white pine/

eastern hemlock

121,465 3 64 5 31 0 69

Eastern white pine 377,647 8 50 14 35 1 64

Hard maple/

basswood

100,322 2 35 17 45 3 52

Red maple/lowland 73,793 2 44 0 35 21 44

Remaining forest 

types (<70,000 

acres each)

266,761 6 44 0 35 21 44

Northern red oak 283,240 6 28 14 57 0 43

Red maple/upland 244,223 5 29 11 61 0 39

Eastern hemlock 85,320 2 25 10 65 0 35

Sugar maple/

beech/

yellow birch

2,094,740 44 21 7 71 0 29

Balsam fir 211,948 4 8 2 89 1 10

Red spruce/

balsam fir

131,144 3 0 7 93 0 7

Paper birch 200,420 4 3 3 95 0 5

Red spruce 100,583 2 5 0 95 0 5
86 | ECOSYSTEM INDICATORS AND SERVICES

Table 7.—Summary of contribution by forest type or forest-type group to wildland-urban interface change 

group, New Hampshire (percentages may not add to 100 because of rounding)

WUI change group

Forest type or 

forest-type group

Total 

acres

All 

classes

WUI 

since 

1990 or 

earlier

New WUI 

1990–

2010

Still nonWUI as of 

2010

Potential 

WUI 

decrease

Total area (acres) 

or percentage

4,783,480 100 1,334,515 449,575 2,953,802 45,589 

percent --------------------percent--------------------

Sugar maple/beech/

yellow birch

2,094,740 44 33 35 50 11

Eastern white pine 377,647 8 14 12 4 10

Eastern white pine/

northern red oak/white ash

297,759 6 12 13 3 14

Northern red oak 283,240 6 6 9 6 0

Red maple/upland 244,223 5 5 6 5 0

Balsam fir 211,948 4 1 1 6 6

Paper birch 200,420 4 0 1 6 0

White oak/red oak/hickory 194,118 4 8 7 2 8

Red spruce/balsam fir 131,144 3 0 2 4 0

Eastern white pine/eastern 

hemlock

121,465 3 6 1 1 0

Red spruce 100,583 2 0 0 3 0

Hard maple/basswood 100,322 2 3 4 2 8

Eastern hemlock 85,320 2 2 2 2 0

Red maple/lowland 73,793 2 2 0 1 35

Remaining forest types 

(<70,000 acres each)

266,761 6 7 7 5 8

Ownerships with the greatest proportion of their forest land area remaining as non-WUI 

forest were State (100 percent) and Federal (97 percent) ownerships. The private ownership 

group had the lowest proportion of its forest land remaining in non-WUI conditions in 

2010 (51 percent), followed by the county and local government ownership group (63 

percent). However, the large amount of forest land in private ownership in New Hampshire 

meant that it had 1.7 times the number of acres remaining in non-WUI conditions in 

2010 as State and Federal land combined (Fig. 67). Almost all the forest land undergoing a 

change in WUI status between 1990 and 2010 was in private ownership (Fig. 68). 

In New Hampshire, 84 percent of the forest land had a spatial integrity index value of 

“core” or “high integrity” at both the 30 m and 250 m scales (Fig. 69), as defined by its 

patch size, local forest density, and connectedness. However, of that core or high integrity 

forest land, 33 percent occurred in WUI conditions in 2010, the most recent census data 

available. Between 1990 and 2010 conversions of core and high spatial integrity forest to 

WUI conditions took place at an average rate of 4.5 percentage points per decade.
ECOSYSTEM INDICATORS AND SERVICES | 87

0

10

20

30

40

50

60

70

80

90

100

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

Federal State Other gov't Private

■ WUI since 1990 or before ■New WUI 1990–2010

■Still non-WUI as of 2010 ● Percentage outside WUI in 2010

Forest Land Area (million acres)

Percentage of Forest Land 

Figure 67.—Forest land by ownership group and wildlandurban interface (WUI) change group, New Hampshire.

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

WUI since 1990

or before

■Federal

■State

■ Other gov't

■Private

Forest Land Area (million acres)

New WUI

1990–2010

Still non-WUI

as of 2010

Figure 68.—Forest land by wildland-urban interface (WUI) 

change group and ownership group, New Hampshire.
88 | ECOSYSTEM INDICATORS AND SERVICES

Forested Area

■Core without WUI

■High integrity without WUI

■ WUI in core or high integrity forest

■ Other forest

■Nonforest

Projection: New Hampshire State Plane, NAD83.

Sources: Wildland-urban interface 2010 (Radeloff et al. 2017),

NLCD 2006 (Fry et al. 2011).

Geographic base data are provided by the National Atlas of the USA®. 

Cartography: R. Riemann, USDA Forest Service, June 2019.

Figure 69.—Locations where wildland-urban interface (WUI) conditions occurred within forest 

land calculated to have core or high spatial integrity at two scales, New Hampshire, 2010.

If we look only at core forest, 73 percent of the forest land in New Hampshire had 

a spatial integrity index value of “core” at both scales, but 28 percent of that core 

forest occurred in WUI conditions in 2010. From 1990 to 2010 this core forest was 

converted to WUI conditions at an average rate of 4.0 percentage points per decade.

What this means

Urbanization is affecting an increasing amount of forest area in New Hampshire, 

including unfragmented forest land in otherwise core or high spatial integrity 

situations. A total of 1.3 million acres (28 percent of New Hampshire forest land) 

was in WUI conditions by 1990, and between 1990 and 2010 forest land was still 

converted to WUI conditions at rates greater than 5 percentage points per decade 

in most counties. In addition, these changes were not limited to already fragmented 

forest land. In New Hampshire, forest land in otherwise core and high spatial integrity 

conditions was converted to WUI conditions at an average rate of 4.5 percentage 

points per decade between 1990 and 2010. 
ECOSYSTEM INDICATORS AND SERVICES | 89

Increasing urbanization has the potential to change how New Hampshire forests 

function, exacerbating their vulnerability to threats such as insect pests and diseases, 

nonnative species proliferation, and loss of native species. Diminished function 

hinders their overall resilience in the face of both these threats and the additional 

changes and disturbances expected due to a changing climate. Such changes also 

affect the inherent ecosystem services provided by forest land such as clean water, 

flood protection, clean air, wildlife habitat, and forest products (e.g., Vermont 

Department of Forests, Parks and Recreation 2015). Many of the reported changes 

in forest ecosystems happen over time and thus forest land which has only recently 

become WUI may not look different yet. Changes may be more apparent in forest 

land that has been in WUI conditions for over 30 years. 

Given the well-documented negative effects of residential development on forest 

land and the amount of forest land occurring in WUI conditions, how we manage 

those residential areas is of great importance. Strategies are available to reduce the 

effects of those residential land uses on surrounding forest land. In addition, planning 

interventions are almost certainly required to maintain remaining forest connectivity.

Urban Forests

Background

Urban forests include all trees growing in urban areas. More than 80 percent of the 

U.S. population lives in urban areas. Trees in cities and towns offer a wide range 

of benefits to urban residents, including the improvement of air and water quality, 

aesthetic appeal and visual barriers, mitigation of rainfall runoff and flooding, and 

lower noise impacts. Given the ecological and economic importance of urban forests, 

there is a need to quantify and monitor this critical resource.

Historically, the focus of the FIA inventory had been to collect information on 

trees that were part of a forest at least 1 acre in size with a natural or unmaintained 

understory. Because many urban trees do not fall into this category, they were not 

captured in the traditional FIA inventory. To address this data gap and improve urban 

forest monitoring, FIA established a national urban forest inventory program in 2014 

and began monitoring in urban areas, focusing on the 100 most populous cities. The 

urban FIA program uses established FIA monitoring methods, database and reporting 

tools, and statistical techniques, along with i-Tree software tools that quantify 

ecosystem services. The ultimate goal of this effort is to have a seamless reporting 

system that uses the existing FIA protocols to provide new and valuable information 

on trees in previously unmeasured areas.
90 | ECOSYSTEM INDICATORS AND SERVICES

What we found

According to the 2010 U.S. Census, New Hampshire has 412,000 acres of urban land, 

which covers 7.2 percent of the State’s land area (U.S. Census Bureau 2010). While 

this percentage of urban land is modest compared to that of southern New England 

(38 percent), it is above the national average (3.0 percent). The city of Manchester 

and surrounding towns and suburbs in the south account for a large proportion of 

New Hampshire’s urban area (Fig. 70). Urban area grew slightly in New Hampshire 

between 2000 and 2010 and is projected to increase 10.5 percent by the year 2060 

(Nowak and Greenfield 2018b).

With the goal of characterizing New Hampshire’s urban tree resource and its associated

benefits and values, FIA will be focusing data collection within the city of Manchester

and will establish a less intensified plot sample in urban areas across the whole State.

Annualized inventory monitoring will begin in Manchester in summer 2020, with tree

and site field data being collected on approximately 200 sample plots within the city.

Data collection on these plots will be spread out over a 7 year cycle; thus one-seventh of

the plots will be visited each year and remeasurement will occur every seventh year.

■State boundary

■Census urban area

■City of Manchester

Figure 70.—Distribution of census urban areas and 

proposed target city for intensified urban Forest 

Inventory and Analysis sampling in New Hampshire.
LITERATURE CITED | 91

The urban FIA inventory in New Hampshire is still being established, so it will be 

several years before data are published based on this field-collected sample; however, 

other studies can be used to derive urban forest attributes. Nowak and Greenfield 

(2018a) conducted a study to quantify urban tree cover and cover change in the 

United States using aerial photointerpretation methods. According to their data, 

trees cover 56 percent of urban land in New Hampshire, which puts the State among 

the five states having the highest percent urban tree cover. Tree cover also remained 

relatively constant between 2009 and 2015. 

Based on the forest cover data and various generalizations and assumptions using data 

specific to New Hampshire, the dollar value of a set of ecosystem services associated 

with the urban forest (carbon sequestration, air pollution removal, avoided energy 

use, and avoided emissions) was estimated and summed. The total value of these 

urban forest benefits in New Hampshire is estimated to be roughly $63 million per 

year (Nowak and Greenfield 2018b).

What this means

New Hampshire’s urban areas are among the most forested in the Nation, with 

trees covering more than half of the state’s urban land. Urban forests are important 

to the health and well-being of the people of New Hampshire, and the ecosystem 

services they provide have both ecological and economic value. For these reasons, 

along with constant forest changes due to such forces as development, storms, aging 

forests, insects and diseases, tree planting, and natural regeneration, it is especially 

important to monitor the urban forest resource and quantify changes in its structure, 

composition, and health. With implementation of the urban inventory program in 

New Hampshire, FIA will soon be able to provide sample-based estimates of urban 

forest structure and associated ecosystem services and value data for Manchester and 

will be poised to monitor changes through time. 

Urban inventory data for cities with completed cycles are available on the Urban Data 

Mart (https://apps.fs.usda.gov/fia/urban/datamart.html) and posted for interactive 

data exploration on the My City’s Trees App (http://tfsfrd.tamu.edu/mycitystrees). 

More information on the FIA program, including field guides, and a national 

implementation status map are available on the Urban FIA Web Site (https://

www.fs.fed.us/research/urban/fia.php).
Spruce/fir forest and flower-filled meadow in the White Mountains. Photo by Randall Morin, USDA Forest Service.
LITERATURE CITED | 93

Literature Cited

Bar-Massada, A.; Radeloff, V.C.; Stewart, S.I. 2014. Biotic and abiotic effects of human settlements in 

the wildland–urban interface. BioScience. 64(5): 429–437. https://doi.org/10.1093/biosci/biu039. 

Bechtold, W.A.; Patterson, P.L., eds. 2005. Forest Inventory and Analysis national sample design 

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

Agriculture, Forest Service, Southern Research Station. 85 p. https://doi.org/10.2737/SRS-GTR-80.

Biomass Energy Resource Center. 2019. 2018 Vermont wood fuel supply study. Prepared for the 

Vermont Department of Forests, Parks, and Recreation. 41 p.

Bregman, T.P.; Sekercioglu, C.H.; Tobias, J.A. 2014. Global patterns and predictors of bird species 

responses to forest fragmentation: implications for ecosystem function and conservation. 

Biological Conservation. 169: 372–383. https://doi.org/10.1016/j.biocon.2013.11.024.

Brose, P.H.; Gottschalk, K.W.; Horsley, S.B.; Knopp, P.D.; Kochenderfer, J.N.; McGuinness, B.J.; 

Miller, G.W.; Ristau, T.E.; Stoleson, S.H.; Stout, S.L. 2008. Prescribing regeneration treatments 

for mixed-oak forests of the mid-Atlantic region. Gen. Tech. Rep. NRS-33. Newtown Square, 

PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. 100 p. https://doi.

org/10.2737/NRS-GTR-33. 

Butler, B.J.; Hewes, J.H.; Dickinson, B.; Andrejczyk, K.; Butler, S.M.; Markowski-Lindsay, M. 2016. 

USDA Forest Service National Woodland Owner Survey: national, regional, and state statistics 

for family forest and woodland ownerships with 10+ acres, 2011-2013. Resour. Bull. NRS-99. 

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

39 p. https://doi.org/10.2737/NRS-RB-99.

Conkling, B.L.; Coulston, J.W.; Ambrose, M.J., eds. 2005. Forest health monitoring: 2001 national 

technical report. Gen. Tech. Rep. SRS-81. Asheville, NC: U.S. Department of Agriculture, Forest 

Service, Southern Research Station. 204 p.

Côté, S.D.; Rooney, T.P.; Tremblay, J.P.; Dussault, C.; Waller, D.M. 2004. Ecological impacts of deer 

overabundance. Annual Review of Ecology, Evolution, and Systematics. 35(1): 113–147. https://

doi.org/10.1146/annurev.ecolsys.35.021103.105725.

Dey, D.C. 2014. Sustaining oak forests in eastern North America: regeneration and recruitment, 

the pillars of sustainability. Forest Science. 60(5): 926–942. https://doi.org/10.5849/forsci.13-114.

Eyre, F.H., ed. 1980. Forest cover types of the United States and Canada. Washington, DC: Society 

of American Foresters. 148 p.

Ferguson, P.F.B.; Conroy, M.J.; Hepinstall-Cymerman, J. 2017. Assessing conservation lands for 

birds in an exurban landscape. Journal of Wildlife Management. 81(7): 1308–1321. https://doi.

org/10.1002/jwmg.21295. 

Ferguson, R.H.; Jensen, V.S. 1963. The timber resources of New Hampshire. Resour. Bull. NE1. Upper Darby, PA: U.S. Department of Agriculture, Forest Service, Northeastern Forest 

Experiment Station. 46 p.

Foster, D.R.; Motzkin, G.; O’Keefe, J.; Boose, E.; Orwig, D.A.; Fuller, J.; Hall, B. 2004. The 

environmental and human history of New England. In: Foster, D.R.; Aber, J.D., eds. Forests in 

time. New Haven, CT: Yale University Press: 43–100.
94 | LITERATURE CITED

Frieswyk, T.; Widmann, R. 2000. Forest statistics for New Hampshire, 1983 and 1997. Resour. Bull. 

NE-146. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northeastern 

Research Station. 130 p. https://doi.org/10.2737/NE-RB-146.

Frieswyk, T.S.; Malley, A.M. 1985. Forest statistics for New Hampshire, 1973 and 1983. Resour. 

Bull. NE-88. Broomall, PA: U.S. Department of Agriculture, Forest Service, Northeastern Forest 

Experiment Station. 100 p.

Fry, J.; Xian, G.; Jin, S.; Dewitz, J.; Homer, C.; Yang, L.; Barnes, C.; Herold, N.; Wickham, J. 2011. 

Completion of the 2006 National Land Cover Database for the conterminous United States.

Photogrammetric Engineering and Remote Sensing. 77(9): 858–864.

Gavier-Pizarro, G.I.; Radeloff, V.C.; Stewart, S.I.; Huebner, C.D.; Keuler, N.S. 2010. Housing 

is positively associated with invasive exotic plant species richness in New England, USA.

Ecological Applications. 20(7): 1913–1925. https://doi.org/10.1890/09-2168.1.

Gonzalez-Abraham, C.E.; Radeloff, V.C.; Hawbaker, T.J.; Hammer, R.B.; Stewart, S.I.; Clayton, M.K. 

2007. Patterns of houses and habitat loss from 1937 to 1999 in northern Wisconsin, USA. 

Ecological Applications. 17(7): 2011–2023. https://doi.org/10.1890/06-1963.1. 

Gormanson, D.D.; Pugh, S.A.; Barnett, C.J.; Miles, P.D.; Morin, R.S.; Sowers, P.A.; Westfall, J.A. 2018. 

Statistics and quality assurance for the Northern Research Station Forest Inventory and Analysis 

Program. Gen. Tech. Rep. NRS-178. Newtown Square, PA: U.S. Department of Agriculture, Forest 

Service, Northern Research Station. 25 p. https://doi.org/10.2737/NRS-GTR-178.

Guo, Q.; Riitters, K.H.; Potter, K.M. 2018. A subcontinental analysis of forest fragmentation effects 

on insect and disease invasion. Forests. 9(12): 744. https://doi.org/10.3390/f9120744.

Hane, E.N. 2003. Indirect effects of beech bark disease on sugar maple seedling survival. Canadian 

Journal of Forest Research. 33(5): 807–813. https://doi.org/10.1139/x03-008.

Heath, L.S.; Hansen, M.; Smith, J.E.; Miles, P.D.; Smith, B.W. 2009. Investigation into calculating 

tree biomass and carbon in the FIADB using a biomass expansion factor approach. In: 

McWilliams, W.; Moisen, G.; Czaplewski, R., comps. Forest Inventory and Analysis (FIA) 

symposium 2008; 2008 October 21–23; Park City, UT. Proc. RMRS-P-56CD. Fort Collins, CO: 

U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 26 p.

Herms, D.A.; McCullough, D.G. 2014. Emerald ash borer invasion of North America: history, 

biology, ecology, impacts and management. Annual Review of Entomology. 59(1): 13–30. 

https://doi.org/10.1146/annurev-ento-011613-162051.

Houston, D.R. 1994. Major new tree disease epidemics: beech bark disease. Annual Review of 

Phytopathology. 32(1): 75–87. https://doi.org/10.1146/annurev.phyto.32.1.75.

Hunter, W.C.; Buehler, D.A.; Canterbury, R.A.; Confer, J.L.; Hamel, P.B. 2001. Conservation of 

disturbance-dependent birds in eastern North America. Wildlife Society Bulletin. 29(2): 440–455.

Janowiak, M.K.; D’Amato, A.W.; Swanston, C.W.; Iverson, L.; Thompson, F.R., III; Dijak, W.D.; 

Matthews, S.; Peters, M.P.; Prasad, A.; Fraser, J.S.; Brandt, L.A.; Butler-Leopold, P.; Handler, S.D.; 

Shannon, P.D.; Burbank, D.; Campbell, J.; Cogbill, C.; Duveneck, M.J.; Emery, M.R.; Fisichelli, N.; 

Foster, J.; Hushaw, J.; Kenefic, L.; Mahaffey, A.; Morelli, T.L.; Reo, N.J.; Schaberg, P.G.; Simmons, 

K.R.; Weiskittel, A.; Wilmot, S.; Hollinger, D.; Lane, E.; Rustad, L.; Templer, P.H. 2018. New 

England and northern New York forest ecosystem vulnerability assessment and synthesis: 

a report from the New England Climate Change Response Framework project. Gen. Tech. 

Rep. NRS-173. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern 

Research Station. 234 p. https://doi.org/10.2737/NRS-GTR-173.
LITERATURE CITED | 95

Jin, S.; Yang, L.; Danielson, P.; Homer, C.G.; Fry, J.A.; Xian, G. 2013. A comprehensive change 

detection method for updating the National Land Cover Database to circa 2011. Remote 

Sensing of the Environment. 132: 159–175. https://doi.org/10.1016/j.rse.2013.01.012.

Kingsley, N.P. 1976. The forest resources of New Hampshire. Resour. Bull. NE-43. Upper Darby, 

PA: U.S. Department of Agriculture, Forest Service, Northeastern Forest Experiment Station. 71 p.

Klem, D., Jr. 2009. Avian mortality at windows: the second largest human source of bird mortality 

on Earth. In: Rich, T.D.; Arizmendi, C.; Demarest, D.W.; Thompson, C., eds. Proceedings of the 

fourth international Partners in Flight conference: tundra to tropics—connecting birds, habitats 

and people; 2008 February 13–16; McAllen, TX. McAllen, TX: Partners in Flight: 244–251.

Kurtz, C.M. 2013. An assessment of invasive plant species monitored by the Northern Research 

Station Forest Inventory and Analysis Program, 2005 through 2010. Gen. Tech. Rep. NRS-109. 

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

70 p. https://doi.org/10.2737/NRS-GTR-109.

Liebhold, A.M.; MacDonald, W.L.; Bergdahl, D.; Mastro, V.C. 1995. Invasion by exotic forest pests: 

a threat to forest ecosystems. Forest Science Monograph. 30: 1–49. https://doi.org/10.1093/

forestscience/41.s1.a0001.

Litvaitis, J.A.; Sherburne, J.A.; Bissonette, J.A. 1985. Influence of understory characteristics on 

snowshoe hare habitat use and density. Journal of Wildlife Management. 49(4): 866–873. https://

doi.org/10.2307/3801359.

Loss, S.R.; Will, T.; Marra, P.P. 2013. The impact of free-ranging domestic cats on wildlife of the 

United States. Nature Communications. 4: article 1396. https://doi.org/10.1038/ncomms2380. 

Mack, R.N.; Simberloff, D.; Lonsdale, W.M.; Evans, H.; Clout, M.; Bazzaz, F.A. 2000. Biotic 

invasions: causes, epidemiology, global consequences, and control. Ecological Applications. 

10(3): 689–710. https://doi.org/10.1890/1051-0761(2000)010[0689:bicegc]2.0.co;2.

McCaskill, G.L.; McWilliams, W.H.; Barnett, C.J.; Butler, B.J.; Hatfield, M.A.; Kurtz, C.M.; Morin, 

R.S.; Moser, W.K.; Perry, C.H.; Woodall, C.W. 2011. Maine’s forests 2008. Resour. Bull. NRS-48. 

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

62 p. [DVD included]. https://doi.org/10.2737/NRS-RB-48.

McClure, M.S.; Salom, S.M.; Shields, K.S. 2001. Hemlock woolly adelgid. FHTET-2001-03. 

Morgantown, WV: U.S. Department of Agriculture, Forest Service, Forest Health Technology 

Enterprise Team. 14 p.

McWilliams, W.H.; Westfall, J.A.; Brose, P.H.; Dey, D.C.; Hatfield, M.; Johnson, K.; Laustsen, K.M.; 

Lehman, S.L.; Morin, R.S.; Nelson, M.D.; Ristau, T.E.; Royo, A.A.; Stout, S.L.; Willard, T.; Woodall, 

C.W. 2015. A regeneration indicator for Forest Inventory and Analysis: history, sampling, 

estimation, analytics, and potential use in the midwest and northeast USA. Gen. Tech. Rep. 

NRS-148. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern 

Research Station. 74 p. https://doi.org/10.2737/NRS-GTR-148.

Miles, P.D.; Smith, W.B. 2009. Specific gravity and other properties of wood and bark for 156 tree 

species found in North America. Res. Note NRS-38. Newtown Square, PA: U.S. Department of 

Agriculture, Forest Service, Northern Research Station. 35 p. https://doi.org/10.2737/NRS-RN-38.

Mockrin, M.H.; Locke, D.H.; Stewart, S.I.; Hammer, R.B.; Radeloff, V.C. 2019. Forests, houses, or 

both? Relationships between land cover, housing characteristics, and resident socioeconomic 

status across ecoregions. Journal of Environmental Management. 234: 464–475. https://doi.

org/10.1016/j.jenvman.2018.12.001.
96 | LITERATURE CITED

Morin, R.S.; Barnett, C.J.; Brand, G.J.; Butler, B.J.; Domke, G.M.; Francher, S.; Hansen, M.H.; 

Hatfield, M.A.; Kurtz, C.M.; Moser, W.K.; Perry, C.H.; Piva, R.; Riemann, R.; Woodall, C.W. 2011. 

New Hampshire’s Forests 2007. Resour. Bull. NRS-53. Newtown Square, PA: U.S. Department 

of Agriculture, Forest Service, Northern Research Station. 56 p. [DVD included]. https://doi.

org/10.2737/NRS-RB-53.

Morin, R.S.; Barnett, C.J.; Butler, B.J.; Crocker, S.J.; Domke, G.M.; Hansen, M.H.; Hatfield, M.A.; 

Horton, J.; Kurtz, C.M.; Lister, T.W.; Miles, P.D.; Nelson, M.D.; Piva, R.J.; Widmann, R.; Wilmot, 

S.; Woodall, C.W.; Zaino, R. 2015a. Forests of Vermont and New Hampshire 2012. Resour. 

Bull. NRS-95. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern 

Research Station. 80 p. [DVD included]. https://doi.org/10.2737/NRS-RB-95.

Morin, R.S.; Liebhold, A.M. 2015. Invasions by two non-native insects alter regional forest species 

composition and successional trajectories. Forest Ecology and Management. 341: 67–74. https://

doi.org/10.1016/j.foreco.2014.12.018.

Morin, R.S.; Liebhold, A.M.; Gottschalk, K.W. 2009. Anisotropic spread of hemlock woolly adelgid 

in the Eastern United States. Biological Invasions. 11(10): 2341–2350. https://doi.org/10.1007/

s10530-008-9420-1.

Morin, R.S.; Lombard, K. 2013. New Hampshire’s forest resources, 2012. Res. Note NRS-172. 

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

4 p. https://doi.org/10.2737/NRS-RN-172.

Morin, R.S.; Randolph, K.C.; Steinman, J. 2015b. Mortality rates associated with crown health for 

eastern forest tree species. Environmental Monitoring and Assessment. 187(3): 87. https://doi.

org/10.1007/s10661-015-4332-x.

National Centers for Environmental Information. 2019. Climate at a glance: statewide time series.

Department of Commerce, National Oceanic and Atmospheric Administration, National Centers 

for Environmental Information. Available at https://www.ncdc.noaa.gov/cag/statewide/timeseries (accessed May 2, 2019).

New Hampshire Fish and Game Department [NH FGD]. 2015. New Hampshire Wildlife Action

Plan 2015. Concord, NH. Available at https://www.wildlife.state.nh.us/wildlife/

wap.html (accessed October 1, 2019).

Nowak, D.J.; Greenfield, E.J. 2018a. Declining urban and community tree cover in the 

United States. Urban Forestry and Urban Greening. 32: 32–55. https://doi.org/10.1016/j.

ufug.2018.03.006.

Nowak, D.J.; Greenfield, E.J. 2018b. US urban forest statistics, values, and projections. Journal of 

Forestry. 116(2): 164–177. https://doi.org/10.1093/jofore/fvx004.

Orwig, D.A.; Foster, D.R.; Mausel, D.L. 2002. Landscape patterns of hemlock decline in New 

England due to the introduced hemlock woolly adelgid. Journal of Biogeography. 29(10–11): 

1475–1487. https://doi.org/10.1046/j.1365-2699.2002.00765.x. 

Pimentel, D.; Lach, L.; Zuniga, R.; Morrison, D. 2000. Environmental and economic costs 

of nonindigenous species in the United States. BioScience. 50(1): 53–65. https://doi.

org/10.1641/0006-3568(2000)050[0053:eaecon]2.3.co;2. 

Powell, D.S. 1985. Forest composition of Maine: an analysis using number of trees. Resour. Bull. 

NE-85. Broomall, PA: U.S. Department of Agriculture, Forest Service, Northeastern Forest 

Experiment Station. 40 p.
LITERATURE CITED | 97

Radeloff, V.C.; Helmers, D.P.; Kramer, H.A.; Mockrin, M.H.; Alexandre, P.M.; Bar Massada, A.; 

Butsic, V.; Hawbaker, T.J.; Martinuzzi, S.; Syphard, A.D.; Stewart, S.I. 2017. The 1990–2010 

wildland-urban interface of the conterminous United States—geospatial data. 2nd ed. Fort 

Collins, CO: U.S. Department of Agriculture, Forest Service Research Data Archive. https://doi.

org/10.2737/RDS-2015-0012-2 (accessed January 8, 2020).

Radeloff, V.C.; Helmers, D.P.; Kramer, H.A.; Mockrin, M.H.; Alexandre, P.M.; Bar-Massada, A.; 

Butsic, V.; Hawbaker, T.J.; Martinuzzi, S.; Syphard, A.D.; Stewart, S.I. 2018. Rapid growth of 

the US wildland-urban interface raises wildfire risk. Proceedings of the Natural Academy of 

Sciences. 115(13): 3314–3319. https://doi.org/10.1073/pnas.1718850115.

Riitters, K.; Potter, K.; Iannone, B.V.; Oswalt, C.; Fei, S.; Guo, Q. 2018. Landscape correlates of 

forest plant invasions: a high-resolution analysis across the eastern United States. Diversity and 

Distributions. 24(3): 274–284. https://doi.org/10.1111/ddi.12680. 

Rogers, B.M.; Jantz, P.; Goetz, S.J. 2016. Vulnerability of eastern US tree species to climate change. 

Global Change Biology. 23(8): 3302–3320. https://doi.org/10.1111/gcb.13585.

Ronis, E. 2018. Managing for biodiversity in northeastern forests. The Wildlife Society. http://

wildlife.org/wp-content/uploads/2015/11/Position_Paper_Forest_Biodiversity_FINAL_

DRAFT_11_06_2017.pdf (accessed June 2018).

Russell, F.L.; Zippin, D.B.; Fowler, N.L. 2001. Effects of white-tailed deer (Odocoileus virginianus)

on plants, plants populations and communities: a review. The American Midland Naturalist. 

146(1): 1–26. https://doi.org/10.1016/j.foreco.2016.10.038.

Russell, M.B.; Fraver, S.; Aakala, T.; Gove, J.H.; Woodall, C.W.; D’Amato, A.W.; Ducey, M.J. 2015. 

Quantifying carbon stores and decomposition in dead wood: a review. Forest Ecology and 

Management. 350: 107–128. https://doi.org/10.1016/j.foreco.2015.04.033.

Schaberg, P.G.; Tilley, J.W.; Hawley, G.J.; DeHayes, D.H.; Bailey, S.W. 2006. Associations of calcium 

and aluminum with the growth and health of sugar maple trees in Vermont. Forest Ecology and 

Management. 223(1–3): 159–169. https://doi.org/10.1016/j.foreco.2005.10.067.

Shigo, A.L. 1972. The beech bark disease today in the northeastern U.S. Journal of Forestry. 54: 

286–289.

Shortle, W.C.; Smith, K.T. 1988. Aluminum-induced calcium deficiency syndrome in declining red 

spruce. Science. 240(4855): 1017–1018. https://doi.org/10.1126/science.240.4855.1017. 

Skinner, M.; Parker, B.L.; Gouli, S.; Ashikaga, T. 2003. Regional responses of hemlock woolly 

adelgid (Homoptera: Adelgidae) to low temperatures. Environmental Entomology. 32(3): 

523–528. https://doi.org/10.1603/0046-225x-32.3.523.

Smith, D.M.; Larson, B.C.; Kelty, M.J.; Ashton, P.M.S. 1997. The practice of silviculture: applied 

forest ecology. 9th ed. New York, NY: John Wiley and Sons. 537 p.

Steinman, J. 2000. Tracking the health of trees over time on forest health monitoring plots. In: 

Hansen, M.; Burk, T., eds. Integrated tools for natural resources inventories in the 21st century; 

1998 August 16–20; Boise, ID. Gen. Tech. Rep. NC-212. St. Paul, MN: U.S. Department of 

Agriculture, Forest Service, North Central Research Station: 334–339.

U.S. Census Bureau. 2010. 2010 Census urban and rural classification and urban area criteria. [Data 

file]. U.S. Department of Commerce, Census Bureau. https://www.census.gov/programs-surveys/

geography/guidance/geo-areas/urban-rural/2010-urban-rural.html (accessed January 28, 2020).
98 | LITERATURE CITED

U.S. Environmental Protection Agency. 2018. Inventory of U.S. greenhouse gas emissions and 

sinks: 1990–2016. EPA 430-R-18-003. Washington, DC. https://www.epa.gov/ghgemissions/

inventory-us-greenhouse-gas-emissions-and-sinks-1990-2016 (accessed October 23, 2018).

USDA Forest Service. 1954. The forest resources of New Hampshire. For. Res. Rep. No. 8. 

Washington, DC: U.S. Department of Agriculture, Forest Service, Northeastern Forest 

Experiment Station. 39 p.

USDA Forest Service. 2016. Forest inventory and analysis national core field guide: field 

data collection procedures for Phase 2 plots, ver. 7.1. Washington, DC: U.S. Department of 

Agriculture, Forest Service, Northern Research Station. 432 p. Available at https://www.fia.fs.fed.

us/library/field-guides-methods-proc/index.php (accessed September 30, 2019).

Vermont Department of Forests, Parks and Recreation. 2015. 2015 Vermont forest fragmentation 

report to the Vermont legislature. Montpelier, VT: Vermont Department of Forests, Parks and 

Recreation, Agency of Natural Resources. 54 p. https://fpr.vermont.gov/sites/fpr/files/About_the_

Department/News/Library/FOREST%20FRAGMENTATION_FINAL_rev06-03-15.pdf (accessed 

October 2, 2019).

Vitousek, P.M.; D’Antonio, C.M.; Loope, L.L.; Westbrooks, R. 1996. Biological invasions as global 

environmental change. American Scientist. 84: 468–478.

Ward, J.S.; Montgomery, M.E.; Cheah, C.A.S.-J.; Onken, B.P.; Cowles, R.S. 2004. Eastern hemlock 

forests: guidelines to minimize the impacts of hemlock woolly adelgid. NA-TP-03-04. Newtown 

Square, PA: U.S. Department of Agriculture, Forest Service, Northeastern Area, State and Private 

Forestry. 28 p.

Westfall, J.A.; Frieswyk, T.; Griffith, D. 2009. Implementing the measurement interval midpoint 

method for change estimation. In: McRoberts, R.E.; Reams, G.A.; Van Deusen, P.C.; McWilliams, 

W.H., eds. Proceedings of the eighth annual forest inventory and analysis symposium; 2006 

October 16–19; Monterey, CA. Gen. Tech. Rep. WO-79. Washington, DC: U.S. Department of 

Agriculture, Forest Service: 231–236.

Widmann, R.H.; Crawford, S.; Barnett, C.; Butler, B.J.; Domke, G.M.; Griffith, D.M.; Hatfield, M.A.; 

Kurtz, C.M.; Lister, T.W.; Morin, R.S.; Moser, W.K.; Perry, C.H.; Riemann, R.; Woodall, C.W. 

2012. New York’s Forests 2007. Resour. Bull. NRS-65. Newtown Square, PA: U.S. Department 

of Agriculture, Forest Service, Northern Research Station. 64 p. [DVD included]. https://doi.

org/10.2737/NRS-RB-65.

Widmann, R.H.; Crawford, S.; Kurtz, C.M.; Nelson, M.D.; Miles, P.D.; Morin, R.S.; Riemann, R. 

2015. New York Forests, 2012. Resour. Bull. NRS-98. Newtown Square, PA: U.S Department 

of Agriculture, Forest Service, Northern Research Station. 128 p. https://doi.org/10.2737/NRSRB-98.

Woodall, C.W.; Heath, L.S.; Domke, G.M.; Nichols M. 2011. Methods and equations for estimating 

aboveground volume, biomass, and carbon for forest trees in the U.S.’s national inventory, 

2010. Gen. Tech. Rep. NRS-88. Newtown Square, PA: U.S. Department of Agriculture, Forest 

Service, Northern Research Station. 30 p. https://doi.org/10.2737/NRS-GTR-88.

Woodall, C.W.; Walters, B.F.; Oswalt, S.N.; Domke, G.M.; Toney, C.; Gray, A.N. 2013. Biomass and 

carbon attributes of downed woody materials in forests of the United States. Forest Ecology and 

Management. 305: 48–59. https://doi.org/10.1016/j.foreco.2013.05.030.
APPENDIX | 99

Appendix

Common and Scientific Names of Tree 

Species Mentioned in this Report

Common name Scientific name

balsam fir Abies balsamea

striped maple Acer pensylvanicum

red maple Acer rubrum

sugar maple Acer saccharum

yellow birch Betula allegheniensis

sweet birch Betula lenta

paper birch Betula papyrifera

hickory Carya spp.

American beech Fagus americana

white ash Fraxinus americana

black ash Fraxinus nigra

green ash Fraxinus pennsylvanica

eastern hophornbeam Ostrya virginiana

red spruce Picea rubens

jack pine Pinus banksiana

red pine Pinus resinosa

eastern white pine Pinus strobus

quaking aspen Populus tremuloides

pin cherry Prunus pensylvanica

black cherry Prunus serotina

white oak Quercus alba

northern red oak Quercus rubra

northern white-cedar Thuja occidentalis

basswood Tilia spp.

eastern hemlock Tsuga canadensis
Morin, Randall S.; Butler, Brett J.; Crocker, Susan J.; Horton, Jonathan; Kurtz, Cassandra M.; 

Lister, Tonya W.; McWilliams, William H.; Nelson, Mark D.; Riemann, Rachel; Walters, Brian F.; 

Woodall, Christopher W. 2020. New Hampshire Forests 2017. Resour. Bull. NRS-119. 

Madison, WI: U.S. Department of Agriculture, Forest Service, Northern Research Station. 

99 p. https://doi.org/10.2737/NRS-RB-119.

The second full remeasurement of the annual inventory of the forests of New Hampshire 

was completed in 2017 and covers more than 4.7 million acres of forest land, with an 

average volume of over 2,300 cubic feet per acre. The data in this report are based on 1,162 

plots located across New Hampshire. Forest land is dominated by the maple/beech/birch 

forest-type group, which occupies 52 percent of total forest land area. Of the forest land, 64 

percent consists of large diameter trees, 25 percent contains medium diameter trees, and 

11 percent contains small diameter trees. The volume of growing stock on timberland has 

continued to increase since the 1980s and currently totals nearly 9.5 billion cubic feet. The 

average annual net growth of growing stock on timberland from 2012 to 2017 was over 180 

million cubic feet per year. Additional information is presented on forest attributes, land use 

change, carbon, species composition, regeneration, and forest health. Sets of supplemental 

tables are available online at https://doi.org/10.2737/NRS-RB-119 and contain: 1) tables that 

summarize quality assurance and 2) a core set of estimates for a variety of forest resources.

KEY WORDS: forest resources, forest health, forest products, volume, biomass, carbon, 

habitat

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