chapter 23

CHAPTER 23

TERRESTRIAL BIODIVERSITY &

FORESTRY

There is unrest in the forestThere is trouble with the treesFor the maples want more sunlightAnd the oaks ignore their pleas

The trouble with the maples(and theyre quite convinced theyre right)They say the oaks are just too loftyAnd they grab up all the lightBut the oaks cant help their feelingsIf they like the way theyre madeAnd they wonder why the maplesCant be happy in their shade?

There is trouble in the forestAnd the creatures all have fledAs the maples scream `oppression!`And the oaks, just shake their heads

So the maples formed a unionAnd demanded equal rightsthe oaks are just too greedyWe will make them give us lightNow theres no more oak oppressionFor they passed a noble lawAnd the trees are all kept equalBy hatchet,Axe,And saw ...

Land Use In The United States 1. PUBLIC LANDS- 35 % of land in the United

States is designated as public and is managed by the Federal Government.

- Classified as… A. Multiple-Use Lands B. Moderately Restricted-

use Lands C. Restricted-use Lands

U.S. Land Ownership

Federal35%

Private55%

Native American 3%

State and local 7%

A. Multiple-Use Lands:- 155 Forests and 20 Grasslands of the National Forest System

- Managed by the U.S. Forest Service

& - National Resource Lands

- Managed by the Bureau of Land Management

Uses for Multiple Use Land:Logging MiningLivestock GrazingFarmingOilGas ExtractionRecreationSport Hunting and FishingOff-Road vehicles are restricted to

certain areas

B. Moderately Restricted-Use Lands:

National Wildlife Refuges

- Managed by the U.S. Fish and Wildlife Service

Uses for Moderately Restricted Land

Sport Fishing and HuntingOil and Gas extractionMiningLoggingGrazingFarmingSome Military Action

C. Restricted-Use Lands:National Park System - Managed by the National Park Service

and- 630 road less areas of the National Wilderness Preservation System

Uses for Restricted Use Land:Recreational activitiesCampingNon-motorized vehiclesLoggingSport HuntingHorseback ridingGrazingMiningNo Commercial buildings

permitted

Yellowstone

National parks and preserves National forests National wildlife refuges

National parks and preserves

National forests

National wildlife refuges

I. Managing and Sustaining Forests

Ecological-Support food webs

-Act as sponge

-Influence local climate

-Habitat

Economic-Fuel wood, 50%

-Timber-Pulp-Medicines

1. MAJOR TYPES OF FORESTS

- tropical, temperate, boreal

A. OLD-GROWTH FORESTB. SECOND-GROWTH FORESTC. Tree Plantations (tree farms)

Emergent

Canopy

Understory

Floor

Subsoil

Birds, invertebrates,bats

Birds, reptiles,amphibians,lichens, mosses

Shade-tolerant plants, birds, squirrels,lizards, chipmunks

Rotting debris,worms, insects,bacteria

Nematodes,microrganisms

Bole

Snag

A. OLD-GROWTH FOREST

•Undisturbed by humans and/or natural disasters

•High biodiversity

• Increased recycling of nutrients and good habitat

B. SECOND GROWTH FORESTS

-Result from SECONDARY SUCCESSION

-May result from clearcutting

C. Tree PlantationsUniform ages of one speciesHarvested by clear-cutting as

soon as they become valuableReplanted and clear-cut on

regular cycles

MONOCULTURE:Grow only one type of specimen

*An attempt to produce products more efficiently

Tries to hold back succession

Using DNA Technology to build in resistance and produce stronger trees Test Tube Tree

Characteristics of Monoculture forestry

Production of wood products in a predictable fashion

Even-aged management

Loss of soil nutrients

Does not increase biodiversity

The Strange Side Effects of Trees on Steroids

2. WHAT IS HAPPENING TO THE WORLD’S FORESTS?

-World-wide human activity has reduced the earth’s forest by 46%

-In North America and Europe forests are on the upswing

Annual Deforestation Rates

More than 1% loss0.5–1% loss0–0.5 lossStable or increased forestNo data

3. TYPES OF FOREST MANAGEMENT

- The total volume of wood produced varies as it goes through different stages of growth and succession

Time

Short rotation

Woo

d vo

lum

e or

woo

d bi

omas

s

B

C

A

Long rotations

Old-growth harvest(such as hardwoodsfor furniture)

Years of growth

30

25 1510

5

Clear cut

Weak treesremoved

Seedlingsplanted

- Two basic forest management techniques…

A. Even-Aged Management:- Also called INDUSTRIAL FORESTRY

- Trees are kept as same size and age

-Example: Tree farms

*Extensive research in Germany has shown that soil had become depleted

PA Forest ManagementMost of the forests are Even AgedAverage age of trees 80-120

years

Tree Diameter & Management Important consideration of Even Aged

Management Trees of the same age may vary in diameter

Factors that impact tree diameter: Variation among species growth rates Soil and Site conditions Genetics

DBH (Diameter at Breast Height) can be measured with a Biltmore Stick

E. Measuring and Cutting Trees

1. Hold the stick at breast height (4.5 feet from the ground), 25" from your eye, with the back of the stick against the tree you are measuring.

2. Hold the stick at a right angle to the axis of the tree and keep your eyes level with the stick.

3. Adjust the stick so that the left or zero is in line of sight with the left side of the tree.

4. Without moving your head, shift the line of sight to the right hand side of the trunk.

5. Read the diameter on the stick nearest the point at which the line of sight crosses it.

Using a Biltmore Stick - Diameter

Using a Biltmore Stick - Height 1. Total tree height is measured from the

ground to the top of the tree. Merchantable tree height is measured from the stump height to the point at which the tree is no longer useable.

2. Stand 66 feet from the tree you are going to measure. If the ground is not level, stand on a spot which has about the same elevation as the base of the tree.

3. Hold the stick vertical, 25" from your eye, with the “Height of Tree” side facing toward you.

4. Align the base of the stick at the ground (or at your estimated stump height for merchantable height).

5. Without moving your head, shift your line of sight so you can read the height at the point where your line of sight and the top of the tree intersect (or merchantable height).

Using a Diameter Tape Hold the tape at 4.5 Ft from the 

highest ground level at the base of the tree (Known as DBH)

Arrange the tape horizontally around the trunk.  Any deviation from horizontal will cause you to overestimate dbh, and as dbh squared is used to calculate basal area, basal area can be very much overestimated in this way; and

Pull the tape as tightly as possible.

The Biltmore Stick

Classifying a Forest Based on Predominant Tree Size

3 Categories for describing tree diameter:1.) Seedling-Sapling: DBH < 5”2.) Mid-Size Tree: DBH 5-11”3.) Large Tree: DBH > 11”

B. UnEven-Aged Management:- Trees are kept at a variety of

ages and sizes-Goals are: 1. Biological diversity 2. Long-term sustainable

production of timber 3. Moderate economical

return4. Multiple use of forests

4. HARVESTING TECHNIQUESA. Selective Cutting: - Mature trees are cut singly or in small groups

-reduces crowding -encourages growth -protects against soil erosion

-maintains uneven growth

-Maintains habitat

Selective Cutting

HIGH GRADING- When only the largest and best species are used.

- Problem: Remove the strongest species

- REVERSE NATURAL SELECTION

B. Shelterwood Cutting:-Removes all mature trees in two/three cuttings over a period of 10 years.

-allows natural seeding-keeps seedlings from crowding

-reduces soil erosion-provides good habitat for wildlife

Shelterwood CuttingCut 1

Cut 2

C. Seedtree Cutting:-Harvests nearly all a stand’s trees in one cutting

-Leave a few seed-producing trees behind to regenerate the area.

-Leads to genetic improvement in new stands

Seed-Tree Cutting

D. Clear Cutting:

-Removal of all trees from an area in a single cutting

The area may be…A whole stand A stripA series of patches.

Clear-Cutting

Issues Concerning Clear Cutting

PROS- INCREASE

YIELD- LESS SKILL

NEEDED- INCREASED $- BEST WAY TO

HARVEST TREE FARMS

CONS- LEAVES LARGE

OPENINGS IN FOREST

- REDUCES BIO- DIVERSITY

- INCREASES SOIL EROSION

- FLOODING

E. Strip Cutting:

Type of Clear-cutting Removes a strip of trees along the contour of the land

Narrow enough to allow for natural regeneration

Strips are harvested every 30-40 years

Strip Cutting

Uncut Cut Cut Cut Uncut

6–10 years ago3–5 years ago 1 year ago

5. FOREST SUSTAINABILITY

-Longer rotation of timber growth (point C)

-Use anti-erosion techniques

-Assist Natural Regeneration

6. FOREST PESTS/DISEASEA. Parasitic Fungi:

Chestnut Blight (China)Dutch Elm (Europe)White Pine Blister (Europe)Beech Bark Disease

B. Parasitic Insects:

•Bark Beetles

•Gypsy Moth

•Hemlock woolly adelgid

Forest Pests of Pennsylvania

Hemlock Woolly Adelgid

Gypsy Moth- came from Europe

Eastern Tent Caterpillar

The ladybird beetle, Pseudoscymnus tsugae, is a known predator of the

hemlock woolly adelgid. P. tsugae is a native insect of Japan, where it is

observed to aggressively attack and control the hemlock woolly adelgid,

Adelges tsugae Annand. Beginning in 1992, extensive research efforts were

undertaken in the northeastern United States to breed and release this

ladybird beetle in an effort to combat the hemlock woolly adelgid. Mass rearing and release of P. tsugae in

Pennsylvania began in 1999. Efforts to establish this predator are continuing,

and, to date, more than 117,000 ladybird beetles have been released in

Pennsylvania.

Visit http://www.dcnr.state.pa.us/forestry/pests/index.aspx

to find out more about the Pests that Harm PA Forests

White Pine Weevil

Twolined Chestnut

Borer

The Newest Invasive Threats

Larvae of the beetle feed in the tissues under the bark of ash trees (Fraxinus spp.) causing the girdling and death of branches and entire trees. Adults of the species are active from mid-May until early August. Since its discovery in Michigan, the beetle has been detected in Ohio, Maryland, Virginia, Indiana and neighboring areas in Canada. In Michigan alone, over 7 million ash trees have been lost to this pest. Signs of emerald ash borer include upper crown dieback, woodpecker damage, sinuous galleries under the bark, and "D"-shaped emergence holes.

Girdled Tree by Emerald Ash

Borer

The Asian longhorned beetle was first identified in North America in New York in 1996. Larvae of the beetle feed in the stems and

branches of many hardwood tree species including maple, boxelder, alder, elm, birch, poplar, and willow. Continued feeding can lead to the death of branches and entire trees. Adults of the

species are active from mid-May until early August. Since its discovery in New York, it has become established in Illinois, New

Jersey, and Toronto, Ontario, where it is responsible for the destruction of over 8,000 trees. Recently a new infestation has

been discovered near Carteret, New Jersey.

Signs of Asian longhorned beetle infestation include dieback of the upper crown, sawdust around the tree, and dime-sized, round

emergence holes.

A disease-causing oak mortality was first discovered in California in 1995. Termed

sudden oak death, it was later determined that the causal agent was a newly described fungal

pathogen, Phytophthora ramorum.

Sudden oak death can be recognized by crown dieback, leaf discoloration, or the presence of black

or red ooze bleeding from cankers on the bark. Removal of diseased bark will reveal necrotic tissue surrounded by black zone lines. Homeowners can

help to stop the spread of sudden oak death by landscaping with native plants.

7. FOREST FIRESTypes of Forest Fires:

A. Surface Fires- Burn leaf litter and ground

clutterControlled & Not dangerous*cone bearing trees benefit*

http://activefiremaps.fs.fed.us/#

Surface fire Fig. 23.12a, p. 599

B. Crown Fires- •Burn in the treetops

Crown fire Fig. 23.12b, p. 599

C. Ground Fires- Underground and burn partially decayed leaves or peat

Common in peat bogs

FIRE

*Forest Fire Prevention:

-Controversial policy…

-Since 1972… -Let forest fires burn themselves out as long as not a danger to humans.

-Calls for change after fires of 1994 and 2000.

SHOW SMOKEY THE BEAR VIDEO

*Forest Fire Prevention Techniques:

-Education-Prescribed Burning-Presuppression-Suppression

http://kdka.com/national/texas.oklahoma.fires.2.981359.html

Salt is used as the red fire retardent

Pa Fires - 2002

II. Forest Resources/Management1. Today’s USA

Status:Since 1960, vast increase in the number of tree plantations

USA has set aside protected areas

Forest covers about 1/3 of the lower 48 United States.

Forest are generally bigger and healthier than in 1920.

Virgin forests, 1620

Virgin forests, 1998

National Forest ManagementTimber

Companies-Want to increase logging to satisfy demand…-Improvement of forest health…-Provides jobs…-Provide cheap timber

Environmentalists-Timber from national forest is small % of wood used-Timber from national forests does little to drop prices-Recreation should be the most important use of forest

2. Pennsylvania’s Forest Status

Pennsylvania’s ForestsIn the Past…1630 = 95% forest1907 = 30% forest2000 = 58% forestNo net loss of forestland statewide

in the past several years

Areas of Concern:South East and South Central PA

forests

2 Biggest Problems With PA Forests:

Urban Sprawl Greatest in Southeast White-tailed Deer Browsing- destruction of tree

seedlings

Black BirchBlack Cherry

Red Maple

What do We Do With the Wood?PA forests provide raw materials for:Fine Furniture, Cabinets, Hardwood floors

& Paper $5.5 billion in products 100,000 jobs

86 Billion Board Feet of Lumber

3. How To Reduce Tree Needs

- Increase the efficiency of wood use

- Increase paper recycling-Use alternative fibers

-EX: Kenaf (rapidly growing woody plant)

-Agricultural residue

14

12

10

8

6

4

2

01930 1940 1950 1960 1970 1980 1990 2000 2010

Year

Tim

ber c

ut (b

illio

ns o

f boa

rd fe

et)

Fig. 23.14a, p. 601

Ann

ual r

ecre

atio

nal v

isits

(mill

ions

)

350

300

250

200

150

100

50

01930 1940 1950 1960 1970 1980 1990 2000 2010

YearFig. 23.14b, p. 601

III. Ecological Restoration1. Restoration Ecology - Research and scientific study

devoted to restoring, repairing, and reconstructing damaged ecosystems

Done Through…

-Eliminating disruptive nonnative species

-Holding an ecosystem at a particular desirable stage of succession

-Speeding up natural ecological succession

-Using natural restoration

Forest Conservation

Diversity in Layers

How a Forest Forms