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
