Trends in Connecticut's forests : a half-century of change

Historic, Archive Document

Do not assume content reflects current
scientific knowledge, policies, or practices.

CONNECTICUT'S FORESTS

N AT I ON A ^AGRICULTURAL LIBRARY

Forests provide wood and other products, watershed protection, wildlife habitat, biodiversity, a setting
for recreation, and much more. Highlighted here are significant trends in Connecticut's forests over the
last half-century. Data are summarized from forest inventories conducted by the USDA Forest Service,
which periodically inventories the Nation's forest resources. In cooperation with the Connecticut
Department of Environmental Protection Division of Forestry, the Forest Service completed the fourth
statewide inventory of Connecticut's forests, in 1998.

THE EXTENT OF CONNECTICUT'S
REGROWN FOREST

Forests are the predominant type of natural vegetation in
Connecticut, covering 1 .9 million acres or 60 percent of the
State. Connecticut was not always this heavily forested. Early
settlers here cleared nearly three-fourths of the original forest
for agriculture. Acreage farmed peaked around the middle of
the 1 9th century, and then began a long decline that still contin-
ues. Forests have reclaimed much of the abandoned farmland
through natural regeneration. The upward trend in forest area
peaked during the 1 950s. Since 1 972, the amount of new for-
est land coming from abandoned farms has roughly equaled
losses of forest land to development, with the total amount of
forest land remaining stable. It is unlikely this trend will con-
tinue because there are no longer large amounts of marginal
farmland to revert to forest, and development pressures are in-
creasing on both farm and forest land.

AREA BY LAND USE, 1998

^^^^^^^^1 ^"^v. other
^^^^^^^^^^^ft \ / Farmland

^^^^^B \y 8.7%

other forest land
5.3%

In view of its long history and advanced state of economic
development, the amount of forest in Connecticut is remark-
able. Litchfield County is the most heavily forested (75 percent)
and Fairfield County the least (37 percent).

Forest land is categorized by the USDA Forest Service as
either timberland or noncommercial forest land. Categorizing
forest land is helpful in understanding resource availability and
planning forest management. Timberland is capable of growing
timber crops and is potentially available for harvesting. Ninety-
seven percent of Connecticut's forest land (1 .7 million acres) is
classified as timberland. Noncommercial forest land includes
reserved forest lands, unproductive forests, and urban forests.
Harvesting for timber products on these lands is administratively
restricted or economically impractical. Examples include parks.

wildlife preserves, and mountaintops and wet- lands with poor
growing conditions. Noncommercial forest land has increased
steadily from 17,000 acres in 1953 to 163,200 acres in 1998.
Nearly all of this increase is due to the reclassification of tim-
berland into the noncommercial category. Most noncommer-
cial forest land is in public ownership.

TRENDS IN FOREST-LAND AREA

(Thousands of acres at each inventory)

Inventory date

1953

1972

1985

1998

Timberland

1.973.0

1.805.6

1.784.5

1.696.1

Noncommercial

forest land

17.0

55.2

65.7

163.2

Total forest land

1.990.0

1.860.8

1.850.3

1.859.3

Percent forested

63.5%

59.7%

59.7%

60.0%

Estimated total

land area*

3.135.0

3.116.8

3.101.0

3.101.0

'Estimates of the total land area have changed because of new
measurement techniques and refinements in the classification
of small bodies of water.

PEOPLE AND FORESTS

The size of the population and how people live on the land
are significant forces in shaping the forest. The population
grew by 51 percent to 3.3 million people between 1 953 and 1 998,
making Connecticut the fourth most densely populated state.
Yet it ranks 13th in percentage of forest cover. Few places on
earth have as many people living among so much forest.

Most of Connecticut's forest land is owned by an estimated
102,000 private individuals and enterprises, which hold 84 per-
cent of the state's timberland. State, federal, and other public
owners hold the remaining 16 percent. The numbers of acres
owned strongly influence landowners' motives and management
activities. Owners of large tracts of forest are more likely to
manage their forests for timber products. Private and public
water utilities, own some of the largest forested tracts. Although
many in number, owners with small holdings account for a small
portion of the timberland. Three-fourths of the private forest
landowners have fewer than 1 0 acres and they collectively own
about 9 percent of the timberland. These small tracts are prima-
rily home sites.

The number of owners with fewer than 50 acres of timberland
has increased by 68 percent since 1975. Wildlife biologists
have found that breaking up large tracts of unbroken forest into
many smaller forests by roads, home building, and other land
development has been detrimental to many species of birds
and other wildlife.

TIMBERLAND OWNERSHIP IN CONNECTICUT

Individual
and other
private
84%

Private Timberland
By Size Class of Owner, 1993

Acres
owned

fsize class^

Number of
owners

Total acres
in class

1-9

77,200

126,700

10-49

18,400

404,600

50-99

3,200

202,300

100-499

3,000

379,300

500-999

200

126.700

1,000+

<50

176,800

All size

classes

102.000

1.416.400

MORE LARGE SIZE STANDS

Timberland is classified by the size of trees growing on it
for both timber resource and wildlife habitat purposes. Saw-
timber stands, which have the majority of their stocking in large
trees suitable for sawlogs, have increased in acreage. These
stands have more of the attributes that are beneficial to wildlife:
an understory with herbaceous plants and shrubs that provide
wildlife food and cover habitat; bole cavities for nesting; bark
flaps for feeding sites; and large dead trees, both standing and
on the forest floor.

Poletimber-size stands declined in acreage. Trees in these stands
are not yet mature enough to produce large amounts of nuts and
seeds, and often form dense overstories that inhibit the growth
of understory vegetation.

The area categorized as sapling/seedling and nonstocked stands
has decreased from 29 percent of timberland in 1953 to 5 per-
cent in 1998. Typically, early-successional pioneer tree spe-
cies, along with many shrub and herbaceous plants that need
full sun to grow, are found here. These stands provide unique
nesting and feeding habitats for wildlife.

The shift to the more mature sawtimber-size class shows that
forest habitats are changing. This is good news not only for the
lumber industry but also for many wildlife species. However, the
decline in wildlife species that need early-successional stands,
such as Eastern bluebirds and chestnut-sided warblers, is of
concern to many wildlife biologists. Forests containing all stand-
size classes provide diverse habitats for wildlife, and an even
flow of forest products, and might be more resistant to insect
and disease outbreaks.

TIMBERLAND AREA BY STAND-SIZE CLASS
AND PERCENT OF TOTAL BY INVENTORY YEAR

Sapling-seedling,
nonstocked

Poletimber

Sawtimber

200 400 600 800 1000 1200 1400

Thousands of Acres

□ 1953 □ 1972 □ 1985 □ 1998

TREES HAVE INCREASED IN SIZE
AND NUMBER

How well forests are populated with trees is determined
by measures of tree size and number. Foresters measure
tree diameters at 4-1/2 feet above the ground and refer to this
as diameter at breast height (d.b.h.). Since 1972, the average
d.b.h. of trees 5 inches in diameter or greater has increased
from 8.7 to 9.8 inches. During this period, the average number
of trees per acre, 5 inches d.b.h. or greater, has increased
from 157 to 161.

Changes in the numbers of trees were not distributed evenly
across diameter classes. Since 1972, most of the increase in
the number of trees occurred in diameter classes above 8
inches. Numbers of trees in the 2-, 4-, 6-, and 8-inch classes
have decreased.

NUMBER OF TREES BY DIAMETER CLASS

600

2 4 6 8 10 12 14 16 18 20

Diameter class (inches at breast height)

THE VOLUME OF TREES HAS INCREASED

This increase in size and number of trees has resulted in an
increase in ttie average volume of trees per acre of timber-
land. Volume per acre increased from 799 cubic feet in 1 953 to
1,995 cubic feet in 1998.

AVERAGE VOLUME PER ACRE

2500

2000-

S 1500

o
.a

3 10OO

500

5406

1995

4276

1631

^^^6 2729

799

942

6000

5000

4000

■S

3000 "2
CO

o

2000 ^

1000

1953 1972 1985 1998

Inventory Year
□ Cubic feet □ Board feet

Despite a decrease in timberland area since 1 985, the total
cubic volume of trees increased by 1 6 percent. The portion of
these trees that is large enough to produce sawlogs has in-
creased by 20 percent to now total 9.2 billion board feet.

growth of trees averaged 55.7 million cubic feet and removals
averaged 25.5 million cubic feet. The net growth of wood, which
includes losses due to natural mortality, was about 2.3 times as
much as was being cut or otherwise removed. Sixty-one per-
cent of removals are attributed to harvesting, and 38 percent to
the reclassification of timberland to noncommercial forest land
or conversion to a nonforest use. Oak species accounted for
nearly half of the volume harvested. The surplus growth over
removals yields an annual net increase of 34.8 million cubic
feet — an annual increase of 1 percent. The growth of trees has
exceeded harvesting since the first inventory in 1 953 and today's
well-stocked stands are the result of these steady gains accu-
mulating in the forest.

COMPONENTS OF CHANGE IN
LIVE VOLUME ON TIMBERLAND

100.0 ■

80.0 -

1

60.0 ■

u

40.0 ■

J3

3
U

20.0 ■

c

o

0.0 ■

S

-20.0 ■

-40.0
-60.0

79.4

61.2

34.8

-18.2

-26.3

Gross
Growth

Mortality Net Growtti Removals Net Change

/

61% due to harvest

39% due to land use change

RED MAPLE LEADS IN VOLUME

Connecticut's forests contain a diverse mix of species. The
1 998 inventory identified 64 tree species, though many of
these are uncommon. The 10 most common species (listed in
the chart below) account for 88 percent of the cubic-foot vol-
ume. When ranked by volume, red maple is the leading spe-
cies followed by northern red oak, which was the leading spe-
cies in the 1 953 and 1 972 inventories. Ongoing high-grading of
oak stands during harvesting on private land, high oak mortal-
ity following gypsy moth caterpillar outbreaks, and lack of oak
regeneration are significant factors in this change.

CHANGE IN VOLUME OF TOP 10 SPECIES

Red maple
Northern red oak
Ottier red oaks -
Hemlock
Black birch
White pine
White oak
Hickory
White ash
Sugar maple

-1 -17%

-2 ♦13%
J ♦32%

J

*4%

1,^14%

□ 1985

□ 1998

j -3%

-0 3%

100

200

— I I 1

300 400 500

Million cubic feet

— I —

600

I

700

—r—

800

THE VOLUME OF GROWTH IS TWICE
REMOVALS

Forests have increased in volume during the last 50 years,
and also have produced timber products. The 1 998 forest
inventory revealed that on an annual basis since 1 985, the net

FOREST HEALTH

The USDA Forest Service Forest Health Monitoring (FHM)
Program looks at a wide set of indicators that reflect for-
est conditions. One of these measures is crown dieback, or
the percentage of branch tips that are dead. Dieback can be
a sign that the tree is being attacked by an insect or disease
or has other health problems. Few trees in Connecticut mea-
sured by FHM scientists had significant amounts of crown
dieback. Eighty-five percent of the trees measured had little
(1 to 5 percent) or no dieback; only 1 percent of the trees had
dieback greater than 20 percent. Hemlock trees accounted
for the heaviest dieback, most likely attributable to damage
by the hemlock wooly adelgid. Differences in dieback among
species may indicate differences in tree vigor, though some
variations should be expected due to differences in growth
characteristics. Over time, observations of dieback and other
attributes will allow researchers to identify trends and better
evaluate forest conditions.

DIEBACK OF TREES MEASURED IN 1 996-99

All Species
Black birch
White ash
Hemkx:k
White oak
Black oak
Red maple
Northern red oak

38%

47%

I 15% -0.6%

66%

34%

60%

20%

20%

29%

26%

40%

5.7%

18% 1

65%

1 18%

14% 1

75%

|l1%

17% I

72%

1 11%

71%

J 29%

0% 20% 40% 60% 80% 100%

□ No Dieback □ 1-5% □ 6-20% ■>20%

5 ° =

> — <B
W ' Q. a

0] (D O

S tJ o
(0 2 3
■° a-o
5 § K.

5 ^1 a

0 < a.
? 3 «

1 c q
3

< g o

Q. U 3

ill

Q. <g, <B
<B O C

3 = w
■2. o o
o o >

o >i

(b o
*»

B O

-J 33

2 =

?■ 3

2 €

5 3 S

31 CD ±.

(DOC
~ O </>

3 ■
3 2

fi>

'^' 01 = tu ft
-J -n — —

to o

9 3 u

N> O ~

a> —

OT3 =:

— ^ O ft

9. S ?

S 3 !g

9 >

.5- <o

Q>

3 3 «
-I 3 -D

§l5

3 m

s. S

™ S
ST 3

1?2

OJ 3-

^ 9:
- (/>

(S D>

o »
0) c

o c
2. C

§ >

a. g.

cr &

= (A
>?■§.

^5 3

9. 3

-. 0)

O (S
V> 0)

iC "O

* 2
X o
C (□

S. 3
o 3

3. 0)
(D «}

E "

0) Q.
=■ 0)

o o
3 a
<,

o

V)

o

< 2 o
I -J

(Bo*

5 X o

' 1^
a; s»
a o 3.

■S 3. 3

9 § -

o (B m

r* o 3

c =r. <

(fl o ^'

|£i
5 o 3

SSl

^ en D)

3 o o
u 3

CO — •
£.
3 <"

f- o
w ~"

0> Tl
CO o

(t> o

H

m o

> 2!

o

= 3

■o r* D)

n> s.

IQ o

<» 3

Si. S? «

2 3 rr

SOU)
S £ -
<fl < ^

(D ,

Q. S.

-« 2. (B (B

^ ^

~~ o 5L
" •<
Z i£.

<B (fi

Is

S o

<B 01

?!

o «
^ ■ •

f c

■n
o
3

0)

CD
03
<

O
(Q

w ^ w J5

g.3

— Cfl
Z3
<
03

0) o
CD CD O HI

Q. ^
(D

o |.-g

CD ft)

CD ^ Cfl

2.CQ O)

3

CD Crt -1

r" - ■ CD

03 03

c Q-
o
o

3

Q- zj o

_ 3 O -I
O Q. =?■. CD

,2 §■ ^ ^ g
< CO 5^ §

CQ

CD CD
3

O

o o ^
r" ^ CD

W □ CO
5 - CD

o

CO

3 I

o "J

ill
S c ^
o; CD —

CD Q. CD

9.
^ o

CD O

S- ^

CD CO

I CD

03

CD CD
CD cn
C/) W CD

' CQ
CD Q. ^.o

-■ O =1

CD CD CQ £2. =.■

Crt 03 "D
C CD O

Crt o
03 3.

CD >

C/3 O"

3 3
Q.CQ

CD CT ^ Tl
^ O ^ i
^ S ^

3 ^
03 o f" 3

§ 3

^ g ° CD

Crt O ^

-. ^ CD 3-
=3 Q) CD

^ 03 w §

^ o =5 S-

ci?.§ i ^

N 2. ^ C^
O O ^

Q. O S2. CD

03 JO. n- °

3 o w £

CD T 2. C/3'

O

o
z
o
m

z

>
z
o

o

CD
C/)

m

3)

I

o
z

0)

Ml

N> =

oil

■Nil