EXAM 2 FORESTRY Flashcards
What is ecophsiology?
ecology and physiology studied together in the context of the environment
What is the importance of understanding ecophysiology?
forest succession mechanics, forest response to climate change, atmospheric chemistry of forests
Basic associated of ecophysiology
animal seed dispersal, microbe accumulators, root symbiosis, consumers
Important site factors that trees interact with
- Climate- solar radiation, temperature, available moisture
- Soil- physical, chemical and biological properties, soil and water movement
- topography - microsite and mesosite
factors related to plant distribution
- temperature
- moisture
What is tolerance?
the ability to withstand stress
What is shade tolerance
plants ability to tolerate different amounts of shade
shade intolerant trees
aspen, paper birch, red pine
very shade tolerant species
sugar maple, eastern hemlock
moderate shade tolerant species
eastern white pine, northern red oak
What is advance regeneration?
seedlings or saplings established naturally without the influence of harvesting under a forest canopy. next crop is already established at harvest
What is the light compensation point?
value at which the rate of photosynthesis is equal to the rate of respiration
relationship between soil properties and tree sustainability
soil and pH affects nutrient growth, soil physical and bulk density affects on root growth
Soil pH
below 5.0 is acidic
5.5-6.5 is mildly acidic
6.5-7.2 is more alkaline
7.2-7.3 is considered alkaline
symbiotic relationship between fungi and roots
increases surface area: increase in H2O and nutrient uptake
Definition of silviculture
use of sustainable management practices to establish or guide the development of forested stands to soulful natural resource objectives
why was silviculture created
created by the Germans when they experience a wood shortage
crown classifications
Dominant: sunlight at the top and the sides
Codominant: sunlight at the top and little on the sides
Intermediate: only sunlight on the top
suppressed: no direct sunlight
Even-Aged vs Uneven-Aged
Even-aged: dominant trees are all about the same age
uneven aged: stand has 3 or more age classes
Describe tree size using an age class system
Seedling: 1-5 years, <3 ft tall
Sapling: 5-15 years,> 3ft tall to <4 in DBH
Pole: 15-60 years,> 4 in DBH to <8 in DBH
Mature: 60-150 years, height and diameter slows
Old growth: >150 years, age and stand attributes depend
Tree Regeneration systems: Clear Cut
Most of the trees removed,Ideal with intolerant species
Mimic severe disturbance, planting or direct seeding, natural seeding (limits of seed dispersal, strips, or patch clearcut), advanced regeneration, and stump sprouting
Tree Regeneration Systems: Seed Tree
Scattered trees left after harvest (seed source)
Ideally crop trees regenerate
Cons: seed crop and germination variability, competition, with throw shallow rooted trees
Harvest seed trees 5-8 years later
Tree Regeneration System: Shelterwood
Retain sufficient number of trees per unit area
Seed trees, 30-80% canopy
Visual quality is the best of even aged systems
Remove overstory once understory is established
Tree Regeneration System: Coppice
Dependance on vegetative regeneration
Root sprouting (aspen)
Stump sprouting (red maple, northern red oak)
Pros and Cons Natural Regeneration
Pros: lower cost
Cons: nature and probability, too few or too many
Pros and Cons Artificial Regneration
Pros: dependable and predictable
More reliable stand establishment
Better control of species and spacing
Genetic improvements
Cons: higher cost, site prep
Field grown bare root vs container grown seedling
Field grown: grown in a field rather than a pot or other artificial environment
Container grown: plants are grown in containers (pots) rather than the ground
Advantage of mixed stands
More niches filled (soil and arboreal)
Greater pest resilience
Diversity, flexibility, and market prices
Social desires for aesthetics and recreation
Wildlife habitat and refugia
Advantage of Pure stands
Fit valuable species in a stand
Ease with stand management
Reduced harvesting costs and stand entries
Disadvantage of Pure stands
Aesthetics can be reduced
Diversity decreases
Advantage of even-aged stands
Reduce harvest residue – reduced fire risk
Steady income with small woodlots
Favorable odds with species regeneration
wood quality greater
harvest volume greater per harvest
uniform growth rates
disadvantage uneven-aged
Increased harvest cost
More frequent entry, greater admin costs
Increased silviculture knowledge
Increased administration
Intermediate practices: Release Treatment
fire desirable species- removed competition and frees resources
best before pole stage
many treatments: fire, herbicide, mechanical
Intermediate practices: Improvement Cuts
used on pole and mature stands
remove low value trees- defected or deformed, diseased or infected
leave the best, cut the rest
Intermediate practices: Thinning
reduces stand density
often in even aged stands
usually total volume does not increase
increases in residual potential size
available light, water and nutrients, increased forest health
Types of Thinning: Below or Low
Removes suppressed and intermediate crown classes
Light thinning: removes smaller DBH trees
Heavy thinning: some codominant trees removed
Types of Thinning: Above or Hight
removes dominant and codominant trees
high grading is not desirable
decreases stand genetics
Types of Thinning: Mechanical
removes rows or strips
relatively quick and economical
response is short-lived: tree growth slows to a limiting factor, must repeat thinning every 10-15 years
Intermediate Practices: Pruning
improves wood quality
more than just cutting: natural target pruning, trees seal, don’t heal
Intermediate Practices: Salvage Cuts
removes trees damaged by wind, fire, insects, disease, drought, flood, or ice storm
harvested before quality decreases
Intermediate Practices: Fertilization
improves growth
limiting factors: nitrogen and phosphorus
proper location to prune a branch
cut the dead branch as close as you can to the branch axil
What are the two land surveys systems used in the US
- Metes and Bonds
- US Public Land Survey
initial point
origin
principal meridian (PM)
North and South Direction
base line (BL)
East and West Direction
Standard Paraelles (SP)
East and West Direction, 24 miles
Guide Meridians (GM)
North and South Direction, 24 miles
Township Lines (TL)
East and West Direction, 6 miles
Range Lines (RL)
North direction, 6 miles
Township
36 miles squared
section
1 mile squared
