Final Exam Flashcards
Why can oak species found on dry sites compete successfully with or without regular fire?
Because few other taxa tolerated the soil conditions.
Upland oaks are typically not the fastest-growing species on good-quality sites. What are 4 factor(s) allow oaks to dominate these sites?
- Regular fire favored oaks because of their thicker bark
- Oak roots will continue to grown while a seedling grows and dies back again and again
- Oaks live longer than pines
- Oak’s vessels are very efficient at moving water
Which oak species are dependent upon periodic fire to dominate moist, fertile (mesic) sites?
white oak (Quercus alba) northern red oak (Quercus rubra)
Outline the successional sequence [=change in species composition] typical of upland forests
in oak-dominated regions of the East.
- Pines were pioneers,
- but with the absence of frequent fires, oaks and chestnut dominated.
- Fire favored thick-barked oaks and chestnut and faster-growing species like maples, beech, sweetgum and yellow-poplar.
- The regions were cleared for agriculture, then abandoned, and are in various stages of succession to oak.
- Over the last few hundred years, agriculture has replaced forests on better soils.
- Chestnut blight eliminated chestnuts as canopy dominant.
- Over the last 100 years, fire suppression has favored thin-barked species, like beech and maples, creating higher density stands.
What species are common pioneers in the oak dominated region?
Virginia pine (Pinus virginiana) shortleaf pine (Pinus echinata) pitch pine (Pinus rigida) loblolly pine (Pinus taeda)
How often are large crops of acorns produced? What is this periodicity called? Why did cyclic fruiting likely develop?
- Every 4-10 years
- Advanced regeneration
- Seedlings will grow and die back, each time the roots will continue to grow.
Outline the differences between the red oak and the white oak groups; consider leaves, fruits,
wood, bark, wildlife, and commercial uses. (Hint: In my crystal ball, I see a chart.)
RED OAKS: Leaves: bristle tips Fruits: 2 yrs., germinate in spring Wood: slack cooperage Bark: ridges, furrows, "ski trails" Wildlife value: acorns less desirable Commercial uses: barrels for storing solids
WHITE OAKS:
Leaves: rounded
Fruits: 1 yr., germinates in fall
Wood: tight cooperage
Bark: narrow scaly ridges, shallow furrows, shaggy
Wildlife value: acorns high value
Commercial uses: barrels for storing liquid
What is the difference between tight and slack cooperage?
Tight cooperage:
The transition from early wood to late wood is abrupt, and the wood pores become naturally plugged with tyloses, making the wood watertight and able to store liquids.
Slack cooperage:
The transition is gradual and the pores lack tyloses, making the wood unsuitable for barrels storing liquids.
Which oak group provides which type of cooperage? Are there any exceptions?
Tight cooperage: white oaks
Slack cooperage: red oaks, except blackjack oak (Quercus marilandica)
How do upland oak species grow to become a member of the middle- or upper-canopy?
Grow slowly and do well in the presence of fire.
They can also dominate on soils that do not support other species.
Why is it difficult to increase the proportion of upland oaks following disturbance (e.g., fire, windthrow or clearcutting) on good sites?
They grow much slower than other species. They depend on regular fire to maintain dominance.
What are tyloses? What do they do?
A balloon-like outgrowth of a parenchyma cell through a pit into the cavity of a plant vessel.
When the transition from early wood to late wood is abrupt, they naturally plug the wood pores, making the wood watertight.
What effect has farming had on the soils of the Piedmont over the last 300 years?
Agriculture has replaced forests on the better soils. It has increased the production of pioneer species.
What effect has farming had on the vegetation of the Piedmont over the last 300 years?
The habit of clearing and abandoning farm fields has increased the proportion of pioneer species.
Compared to the 1600s, the amount of oak in our forests today has almost certainly declined, especially in the foothills and mountains. Why?
Fire suppression has allowed faster-growing species to dominate.
What features allow shortleaf pine to tolerate occasional fires?
By a basal crook: stem turns and lies flat on the soil surface and is protected from fire and able to re-sprout (when it’s young).
How is the U.S. Forest Service “restoring” national forests in Arkansas to the conditions found in the year 1491?
By harvesting certain trees so that the forests are not as dense.
What is the fire return interval in oak forests?
6-15 years
Where do oak-dominated forests occur? (Be able to locate the regions on a map.)
(see map)
On either side of the Mesophytic Forests.
What are the commercially most-valuable oaks in oak-dominated regions?
white oak (Quercus alba) northern red oak (Quercus rubra) black oak (Quercus velutina) chestnut oak (Quercus montana)
What effect has fire suppression had on the forests of the Oak-dominated Region?
It has favored thin-barked species, especially beech and maple, and created stands of higher density.
What adaptations allow upland oaks to cope with fire?
- Advanced regeneration: seedlings grow and die back, each time the roots will continue to grow
- Oaks can move water through vessels
- Thicker bark
Name at least six of the dominant tree species found in the Mesophytic Region.
- yellow-poplar (Liriodendron tulipifera)
- American beech (Fagus grandifolia)
- eastern hemlock (Tsuga canadensis)
- yellow buckeye
- yellow birch
- sweet birch
What geologic history is characteristic of the Mesophytic Region?
It developed on the non-glaciated portions of the Cumberland Plateau. It is the oldest region in the biome.
How does the Mesophytic Region compare to the other regions in tree species diversity?
It is more diverse than the others..
The Mesophytic Region is very similar in species composition to what forest community of the Southern Appalachians?
The coves of the Southern Appalachians
What is the fire return interval in Mesophytic and Beech-Maple forests?
100-300 years
Where is Mesophytic Forest Region found? Be able to locate or draw it approximately on a map.
Top right of AL (through TN, KY, WV) to the lower left of PA
Describe the typical habitat (=site) where growth and development of yellow-poplar is unsurpassed. Be able to locate suitable places on a topographic profile.
Concave lower slopes with moist, well-drained, loose soil and northern or eastern aspects.
What percentage of the seeds of yellow-poplar are viable (will germinate)?
10%
How does yellow-poplar compensate for this low viability?
Produces thousands of seeds
Is yellow-poplar tolerant of fire? Why or why not?
No, it does better in fire-controlled areas. Dominates because of fast growth.
Seedlings and saplings have thin bark and do not survive fire.
In what area is yellow-poplar a common pioneer on old fields or after major disturbances?
Disturbances like harvesting and clear cutting
Why has the amount of yellow-poplar increased over the last 100 years, especially in the foothills and mountains?
Fire suppression and harvesting or clear cutting
Where is the Beech–Maple forest region located? Be able to identify or draw (approximately) the region on a map.
MI, IN, OH and around the great lakes
Name the two tree species that dominate the Beech–Maple region.
American beech (Fagus granifolia) sugar maple
Why has much of the Beech-Maple region been converted to agriculture, and oaks provide a larger proportion of the forest cover?
More productive soils has led to much of it being converted to agriculture. Oaks do better in the drier, less-fertile soils.
What is the fire return interval in Beech-Maple forests?
100-300 years
Are beech and maple tolerant of fire? Why or why not?
No because of their thin bark
What species is extensively used in the production of maple syrup?
sugar maple
How is maple syrup made?
Holes are drilled in maple trees at a specific time and temperature. Sap is collected into buckets, then boiled so that the water evaporates. The syrup is filtered and contained.
Where is the Hemlock–White Pine–Northern Hardwoods region located? Be able to identify or draw the region (approximately) on a map.
On either side of the great lakes all the way to Maine (going through the bottom right of Ontario and bottom of Quebec) and down into PA.
Name the tree species that dominate the Hemlock–White Pine–Northern Hardwoods region.
American beech (Fagus grandifolia) northern red oak (Quercus rubra) eastern hemlock (Tsuga canadensis) sugar maple yellow birch basswood
How does white pine differ morphologically from all of the other natural pines in the East?
Has uninodal growth, one whorl each year
What factor is responsible for the extensive white pine stands that once dominated
Pennsylvania and the Lake States?
Catastrophic fires eliminated hardwoods.
Abandoned farmland in New England often regenerated to white pine.
Until about 1900, what species supplied most of the lumber used to build northern cities?
white pine (Pinus strobus)
England imported tree-length white pine logs. Why?
For ship masts, because they were tall enough to make out of a single piece.
Is white pine a fire species? If so, what type of fire regime and how does it cope with fire?
Will survive infrequent, large fires because the older trees will survive.
Why did many areas that were harvested from 1870-1920 regenerate to species other than white pine? What species replaced white pine on sites formerly occupied by white pine?
Little thought was given to securing regeneration and controlling erosion. The logging debris left after harvesting caused massive fires that destroyed the humus layer.
aspen (Populus)
jack pine
paper birch
More recently, black cherry (prunus serotina)
In what geographic region is the growth and development of black cherry unsurpassed?
In central PA
When the high-quality stands of white pine were harvested in Pennsylvania, many areas regenerated naturally to black cherry. But since that time, regeneration of black cherry in
Pennsylvania has been problematic. Why?
Because white-tail deer are eating all of the seedlings and over browsing.
Name two important pioneer tree species in the Hemlock-white pine-northern hardwoods region.
eastern white pine (Pinus strobus) black cherry (Prunus serotina)
Why is the fire return interval of the Hemlock-White Pine-Northern Hardwoods forest much longer than the interval found in Oak-dominated forests?
Reasons are not completely clear.
The combination of moderately high rainfall, a cooler/wetter climate, abundant swamps and lakes and much lower ignition rates by humans.
Native Americans were not as high in population, and were hunter/gatherers, so burning the forest was not necessary.
What was the principal species harvested from this region when the “virgin” forest was cut between about 1870 and 1920? (Remember: it was logging, not clearcutting!)
eastern white pine (Pinus strobus)
What is the timber line? Which mountains in North America contain a “true” timber line, consider the following: Northern Appalachians, Central Appalachians, Southern Appalachians, Rocky Mountains, Cascades and Sierra Nevada ?
The line on a mountain where trees can not grow above it. Grasses are above the timberline.
Rocky mountains
What is krummholz?
A forest of stunted trees near the timberline of a mountain.
Name and locate the principal forest region of Canada.
Boreal Forest: Most of Canada except for in the southeast (Hemlock-White Pine-N. Hardwoods) and in the south central region where prairies are found and the southwest.
Which forest region is the largest (most acres) in North America?
The Boreal Forest
What is the Boreal Forest called in Europe?
Taiga
Describe the general climate of the Boreal Forest.
Cool summers and cold winters, 15-30 inches of annual rain, glacial deposits.
Name the principal tree species found on upland sites in the Boreal Forest.
Spruce-Fir
What type of vegetation occurs north of the Boreal Forest?
Tundra:
Non-forested areas covered with grasses, grass-like plants and low shrubs, especially willow (Salix) and birch (Betula).
Where else on earth are Boreal Forests found?
Europe and Asia
How did bogs develop?
They started with a block of ice that melted, creating a lake.
Bogs develop in wet depressions filled partly or completely with organic matter, owing to slow decomposition.
Name the two trees that dominate bogs.
black spruce
eastern larch
What is the fire return interval in bogs?
100-200 years
How did the sandy, outwash plains develop? Name the one principal species found on these plains.
These plains develop on sandy soil deposited by outwash from melting glaciers.
jack pine
To what types of fires is jack pine well-adapted? What is the fire return interval?
Infrequent, high-intensity fires
50-100 years
Name four adaptations of jack pine to fire.
Thin bark, poorly pruned, high density, short needle length, (but cones are not serotinous)
Name two other species with similar adaptations to fire.
sand pine Virginia pine (Pinus virginiana)
What two tree species occur at high elevations in the Southern Appalachians in what is sometimes considered to be a southern extension of the Boreal Forest?
red spruce (Picea rubens) Frasier fir
What and where is the tallest peak in the Appalachians?
Mount Mitchell
6,684 ft.
What two genera generally dominate temperate zone mountains at high elevation and at high latitude in the Northern Hemisphere?
willow (Salix)
birch (Betula)
Outline the rainfall patterns in eastern North America.
Higher rainfall: About 40-60 inches, some parts 60-80 inches in the southeastern US
Outline the general rainfall patterns for the central and western United States.
Lower rainfall: Average 10-20 inches, some parts less than 10 inches
How much annual precipitation is usually needed to form closed forests?
Over 18”
What non-forest regions occur west of the Oak-dominated region?
Immediately west: Tall Grass Prairies
Great Plains and North American Deserts
Why did tall-grass prairies occur in Iowa, Illinois, southern Wisconsin and portions of Michigan and Ohio, areas that otherwise have sufficient rainfall to be forested?
Frequent (every 1-3 years) fires and grazing by bison favored grasses.
What grass species are especially important in the tall grass prairies?
little bluestem
big bluestem
Why is central North America covered with short grass prairies?
Low precipitation (12-15 inches annually)
What species of grass are important in the short grass prairies?
buffalo grass
grama grass
Why is western North America very arid?
A result of mountain rain shadows and global wind circulation patterns that restrict humid air masses from entering the region.
In what season does most precipitation fall in the Rockies?
winter
What and where is the highest peak in the U.S. Rockies?
Mt. Elbert (14,433 ft.) in CO
What is the approximate percentage of forest cover in the Rocky Mountains?
About 30%
Explain how the lower elevations of portions of the Cascades and the heavily moisture-laden storm clouds strongly influence the species composition of the Inland Empire.
a
Why are forests in the Rockies often not continuous over large areas?
Elevation, rainfall, aspect, rugged topography and fire history are all factors controlling the vegetation.
Name the six zones with woody vegetation encountered while climbing the Rocky Mountains.
- Transition Zone
- Woodland Zone
- Submontane Zone
- Montane Zone
- Subalpine Zone
- Timberline
What type of vegetation occurs above the timberline in the Rockies?
grasses
How much rainfall do the deserts of western North America receive?
Most areas receive less than 12 inches
Name two woody species that occur in the Transition Zone.
mountain mahogany
sagebrush
How much annual precipitation does the woodland zone receive?
15-18 inches
What is the major factor that dominates competition among trees in the Woodland Zone?
Rooting space for water
What species is found in the Sub-montane Zone of the Rockies?
Ponderosa pine (Pinus ponderosa)
How does the vegetation of this zone differ today, compared to the 1800s?
Originally a fire-maintained savanna with widely spaced trees, but recent fire exclusion policies have favored closely-spaced trees that burn catastrophically.
Describe the restoration work being accomplished by the U.S. Forest Service in the Sub-
montane zone.
Removing the younger trees that are less than 150 years old
What species dominates the Montane Zone of the Rockies?
Douglas-fir (Pseudotsuga menziesii var. glauca)
Name four species that regenerate after severe fires in the Rocky Mountains.
- western white pine
- western larch
- lodgepole pine (Pinus contorta)
- trembling aspen (Populus tremuloides)
To what types of fire is lodgepole pine adapted?
Infrequent, catastrophic fires
What fire adaptations does lodgepole pine have?
Dense stands Short needles Serotinous cones Thin bark Don't prune well
What northern and southern species are similar in ecology to lodgepole pine?
Virginia pine (Pinus virginiana)
jack pine
sand pine
Where geographically is the Inland Empire?
Mountains that separate Idaho and Montana
What two tree timber species grow abundantly in the Inland Empire?
western white pine
western larch
Where geographically is the Great Basin?
Parts of Utah and most of Nevada
What tree species dominates the Great Basin? Why?
trembling aspen (Populus tremuloides) Not much rainfall or many fires.
How does trembling aspen generally reproduce?
Sprouts from the roots and forms large clones (genetically identical individuals).
Why is aspen well-adapted to fire?
Because it sprouts clones from roots that can spread up to 1000 acres.
How does overall crown shape of trees change with increases in elevation?
In the higher, subalpine zone, trees have more pointy, triangular crowns because of snow loads.
In the lower, woodland zone, the crowns are more spread out and rounded.
What species are found in the Subalpine Zone?
Engelmann spruce (Picea engelmannii) subalpine fir
Name three environmental factors that strongly influence Subalpine Zone forests.
- high winds
- cool summers, cold winters
- rocky areas and avalanches
Name one tree species found at timberline.
limber pine
What and where is the highest peak in the Cascades? What is the approximate elevation?
Mt. Rainier, SE of Seattle, WA
14,410 ft.
Outline the rainfall patterns of the Pacific coast.
Very high rainfall in WA (over 80), gets lower as you go south, all the way to under 10 south of CA.
Name and locate the two major mountain ranges of the far west.
- Rocky Mountains (From northwest MO, ID, through WY, UT, CO to NM)
- Cascades (Midwestern areas of WA and OR)
Name and locate the two principal forest regions of the Far West. (Be able to locate them on a map.)
- The Chaparral Region (Coastal southern CA)
2. The Pacific Coast Forest Region (From Sitka Island in Alaska to Baja CA)
Where is the largest Chaparral Region located?
Woodland Zone
How has this region changed since the arrival of the Spanish?
Formerly, the region was savanna-like with scattered trees and a grassy understory, maintained by frequent, low-intensity fires.
Now, owing to fire suppression, it is characterized by infrequent, high-intensity wildfires about every 25 years, containing closely spaced shrubby species.
Name the dominant botanical family found in the chaparral.
Ericaceae
Compare the type of fire typical of the chaparral community during the Spanish colonial period to that found today.
Used to be frequent, low-intensity
Now it’s infrequent, high-intensity
Why are the Submontane, Montane and Subalpine zones absent from the Chaparral Region?
Because of low rainfall
What genus is strangely absent from the subalpine zone of the Sierra Nevada?
spruce (Picea)
Why are the Woodland and Submontane Zones absent from the Pacific Coast Forest?
Because of high rainfall
Name the dominant trees found in the Montane Zone of the Cascades.
- Douglas-fir (Pseudotsuga menziesii)
- western hemlock (Tsuga heterophylla)
- western redcedar (Thuja plicata)
Name the dominant trees found in the Subalpine Zone of the Cascades.
- Engelmann spruce (Picea engelmannii)
- subalpine fir
- Alaska yellowcedar
Name the dominants in the Montane Zone of the Coast Range.
- Sitka spruce (Picea sitchensis)
2. western hemlock (Tsuga heterophylla)
Name the dominants in the Subalpine Zone of the Coast Range.
- subalpine fir
- Pacific silver fir
- mountain hemlock
Why has harvesting in national forests declined sharply in the Pacific Northwest?
Because of reserves for the Northern Spotted Owl
What hardwood species regenerates after severe disturbance?
red alder
In what geographic region do the highest-quality Douglas-fir stands occur?
Pacific Coast Forest Region, Cascades
How did the extensive stands of Douglas-fir found in the Cascades develop?
Hardwoods are often pioneer species in the west, succeeded by conifers. They get much older, around 500 yrs.
How does the Rocky Mountain variety of Douglas-fir differ from the Coastal variety in cone bracts and ecology? Be certain to remember the scientific names of each (learned in lab).
Douglas-fir (Rocky Mountain) Pseudotsuga menziesii var. glauca 1. Late successional after disturbance 2. Blue foliage 3. Reflexed cone bracts 4. Moderately large size 5. 300-400 yrs. age
Douglas-fir (Coastal) Pseudotsuga menziesii var. menziesii 1. Early successional after disturbance 2. Green foliage 3. Oppressed cone bracts 4. Large to huge size 5. 500 yrs. age (maybe even 800 yrs.)
What characteristics of Douglas-fir make it an ideal species for fiber-production?
It is the #1 timber in the west, high growth rates
Outline the succession (change over time in species composition) of tree species of the
Cascades.
Hardwoods are often pioneer species in the west, succeeded by conifers.
Name the principal wood product currently obtained from western redcedar.
wood shingles
What did the Native Americans make from western redcedar?
totem poles, lodges and dugout sea-going boats
What are nurse logs?
fallen dead trees where seedlings are established
Name the two places on earth where trees grow to heights over 350 ft.
- In the Pacific Coast Range
2. Southeastern Australia
Compare the form of trees found in the woodland zone with those found in the subalpine zone.
Woodland Zone:
Short, broad-crowned and open to closed stands
Subalpine Zone:
Pointy, triangular crowns, widely scattered trees
