principles of forest ecology and management or…...principles of forest ecology and management...

Principles of Forest Ecology and Management

or… “Forensic Forestry”

Reading the Land

Jonathan Kays University of Maryland Extension

[email protected]

Where Do We Start?

Think Like A Plant

Act Like A Plant

Thinking and Acting Like a Plant

• What is your favorite plant? – Where does it grow? – How do you describe that place? – What is important?

What Does a Plant Need?

• Light • Water • Nutrients

Principles of Forest Ecology

• Site Quality • Shade Tolerance • Forest Succession • Plant Competition • Stand Development • Role of Fire, Insect & Disease, and Herbivory,

Site The environment or system supporting a

forest, which influences trees and plants growing there.

The sum of Soil, Topography, Climate,

Plants, and Animals

Forest Succession on a Site Predictable changes in plant communities

as the competing organisms respond to and modify the environment. These changes will vary depending on the site.

Site is More Important than the Vegetation

• It is more fixed • It is more stable • It is more easily defined • Reflects disturbance

– Strip mine (extreme) – Pasture (subtle) – Harvesting (either)

Maryland Physiographic Regions or “Sites”

Coastal Plain Ridge& Valley

Appalachian

Plateau Piedmont

Great Valley Blue Ridge

Garrett County – Alleghany Plateau

Allegany County - Ridge and Valley

Piedmont Region

Coastal Plain – Southern Maryland

Coastal Plain - Eastern Shore

Soil profile

How does soil develop

or form?

From the bottom or the top?

Plow Layer

Root Mat that holds soil in place

Soil Texture

Tree Height

Sand Clay Heavy Loam Loam Clay

Wetland soils contain organic material, exist with little oxygen, and have developed specialized

ecosystems compared to upland areas.

Consider soils when selecting tree species to plant. Black walnut requires well-drained soils to thrive. This site is

poorly drained so the trees grew poorly and many died.

Where are most of the tree roots?

Most tree roots are found within the top 12 inches of soil

Online Soil Survey http://websoilsurvey.nrcs.usda.gov/app/

The old

You are here!

Faster recycling of nutrients in hardwood

forests compared to pine. WHY?

Best Management Practices protects

the root mat

Slope Position

Are trees larger on the upper or lower slope?

Climate, soil, available water, and nutrients all affect how well a tree grows. If minimum requirements are

not met, a tree may not grow in a given area.

Oaks are better adapted to dry

and shallow hilltop soils, while yellow-

poplar trees are found on more

fertile lower slopes

Certain trees adapt to special conditions

Site Indicator Species

Aspect Direction the slope is

facing

south

west east

north

A B

Solar Radiation What would the line look like for a

south, north, and east facing slope?

6 a.m. Noon 6 p.m

Effect of Aspect on Site Quality

South-facing Slope North-facing

Slope

Quantity of wood produced from an acre of forest depends upon the site quality and is similar to farm crops.

Site Index brings it all together! * By measuring total height and age… * You get site index, the height of a tree at 50 years old… * The taller the tree, the more productive the site.

A

B

Shade Tolerance is the ability of a plant to grow in the shade

• Intolerant Species - intolerant of shade and must have full sunlight to grow

• Tolerant Species - tolerant of shade – does not require full sunlight to grow

• Intermediate tolerance - can grow in partial sunlight or shade

Tolerance, Sunlight, Growth

0% 50% 100% Percentage Sunlight

D B H

Intermediate tolerance – trees that can establish themselves in the understory, but require full

sunlight to mature -- Oak in this example

Tolerant species

Tolerance of Common Forest Trees

Intolerant Intermediate TolerantFull Sun Full ShadeVirginia pine White pine Hemlock

Loblolly pine Hickories Beech

Yellow-poplar Yellow & bl birch Sugar maple

Scarlet & black oak White & red oak Red maple

Black walnut Chestnut oak Silver maple

Green ash Red oak Basswood

Red cedar White ash American holly

Grey birch

Forest Succession Predictable changes in plant communities as

the competing organisms respond to and modify the environment.

Principle: All natural areas change over time,

whether or not you do anything to them.

Stage 1 Herbaceous species

Stage 2 - Old Field

Stage 2 - Old Field of red cedar and goldenrod. It may be beneficial to maintain old field habitats by cutting down invading trees, which can

maintain a diversity of habitats on the property.

Invasive and natural species can take over

Honeysuckle

Kudzu

Grapevine

Old field red cedar being overtopped by shade intolerant tree species (yellow-poplar in this case).

Stage 3 Tree crowns close, sunlight disappears, resulting in dieback of ground vegetation. Poor wildlife value for this stage of succession.

Stage 4

Stage 5 Old Growth

Early Successional Species Vary by Region

Forest succession is the progression of plant communities that begins with shade intolerant plants and ends up with shade tolerant plants.

Virginia Pine early successional forest common on poor soils.

Virginia pine forest that is dying. Beech trees (a late successional species) is established

in the understory and will form the new forest.

Tree Planting--Pushing succession ahead

Forest Harvesting:

Effect on Succession?

Forest succession & wildlife habitat

What Do Plants Compete For?

• Light • Water • Nutrients

Are these trees different ages?

Is tree size a reliable indicator of tree age? Why?

Tree is a factory ... Leaves use sun and

water to produce food...

More leaves… More food… More diameter growth...

The dominance of a tree refers to the position of its crown relative to other trees in the canopy. In even-aged forests, the

more dominant trees have won the competition for light.

Can you label the dominance of the trees in this picture?

Forest Thinning - improve growth & species composition, not regeneration

25 years

25 years

- More leaves… - More food… - More diameter growth...

Leaves use sun and water to

produce food...

Live crown ratio (LCR) is the ratio of the foliage canopy to the total height of the tree.

Epicormic Branching

As buds under bark are exposed to sunlight, they grow and form new branches on the tree bole and can reduce quality. Do not open the forest canopy too much.

This forest was

harvested using sound practices. It would be

hard to tell much

happened here after a few years.

The use of poor harvest practices removes dominant and best trees and leaves the rest. They go by the names of diameter-limit cutting, selection

harvest and high-grading. This amounts to starting over.

Regeneration is the key: Different species have different regeneration strategies

Some species like yellow-poplar, ash and maple need bare soil to germinate seeds…

Heavy seeded species: * Oak * Hickory * Walnut

Stump sprouts from cut hardwood stumps are the most vigorous source of hardwood forest regeneration

If stumps are cut low, sprouts from the root collar will grow into quality trees (right).

Stand development: Year 1: 10,000 stems/ac Year 15: 1,000 stems/ac

Stand Development • A function primarily of

– site quality – Past history – current practices (grazing, for example) – species composition

A photographic history from the Allegheny Plateau in Pennsylvania

(1927-1998)

Development of vertical stratification as trees die,

holes are filled, others seed in.

Forests are resilient

60 years later

Fire releases nutrients, renews,

and favors certain

tree species

Chestnut Blight changed the forest in the span of a few years in the late 1920’s.

Gypsy moths continue to be a

periodic problem.

Emerald Ash Borer new threat to ash trees

Major disturbances, such as hurricanes,

tornadoes, and wind storms.

Other Disturbances

Invasive species

Deer browsing

Southern pine beetle

• No seedling regeneration in the majority of understory plots – Prettyboy….. 84% – Liberty…….. 74% – Loch Raven.. 63%

City of Baltimore, Reservoir Forests Example: intense deer browse leads to the disruption of ecological processes

Deer overabundance negatively impacts forest regeneration and wildlife habitat for other species. Forest birds that used to

nest in the ground vegetation are no longer found.



How do we put all this together to make recommendations for management activities?

What History Are

You Writing?

principles of forest ecology and management or…...principles of forest ecology and management...

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