Envirothon Forestry Station James Miller Harbison State Forest Manager.
FORESTRY: ENVIROTHON
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Transcript of FORESTRY: ENVIROTHON
FORESTRY: ENVIROTHON
About 30% of the world is forested today, but the ratio between forest and population varies immensely.
More than one half of the world's softwood timber (the major forest product) comes from North America and Europe—an area with only a fourth of the world's population.
The forested area of the United States has shrunk in 300 years from about one half to one third of the total land acreage.
The United States and Canada share 16% of the world's forests; the former Soviet Union contains 21%, Africa has 20%, and Latin American has 24%.
FOREST PRODUCTS
FORESTS: ASSESSINGTHE RESOURCE
Depending on “what you want” from a forest will determine what you will and won’t do to it……
Minimally even if you were to preserve the forest you have to know what’s there. That inventory could be the trees (and all other life and non-life there: smaller plants, animals, bacteria, fungi, soils, hydrology, etc.)
WHAT SPECIES?Measuring the diversity or species composition of your forest isalmost always a basic and prime concern. One way to identify treesparticularly if the species are new to you is to use a KEY. Some itemsthat appear in keys that are useful to know are:Leaf shape Branching pattern
Leaf type
WHAT SPECIES?
Other useful characteristics to help identify trees are:
Bark characteristicsFruits
Flowers
WHAT SPECIES?
Tree form Smell (leaves, bark)
Leaf tips
Leaf bases
Site
Buds, twigs
ETC…….
Tree diameter and heights usingBiltmore stick/Merritt hypsometer
TREE DIAMETER (DBH):
D-tapemeasure at4.5 ft fromground….
TREE HEIGHT (TOTAL):
Suunto ClinometerTwo measurements:-One at ground level-The other the very top of the tree
HEIGHT=TOP MEASUREMENT – BOTTOM MEASUREMENT(BE CAREFUL: THERE ARE + and – READINGS YOU CAN GET!)
TREE AGE (at breast height):
Increment corer
TREE AGE (at breast height) CONT’D:
We bore the tree at breast height4.5 feet from the ground….
You can bring the cores back to the lab, mount and sand them and do some DENDROCHRONOLOGY (study of tree rings)..
TREE AGE (at breast height) CONT’D:
POINT SAMPLING
SILVICULTURE“the art and science of controlling the establishment, growth, composition, health, and quality of forests and woodlands to meet the diverse needs and values of landowners and society on a sustainable basis through the application of silvics”
SILVICS:….the life history and general characteristics of forest trees
and stands, with particular reference to environmental factors….
SILVICULTURE CONTROLS:
Stand composition
Stand density
Restock underproductive areas
Protection and salvage
Control rotation length
Facilitate the harvest, management, and use of the forest
Protection of the site and indirect benefits
SILVICULTURAL SYSTEMS
REGENERATION SYSTEMS
Even-aged systemsClearcut systemsCoppice systemsSeed tree systemsShelterwood systems
Uneven-aged systems Group or Individual Selection systems
CAN BE DIVIDED INTO THREE BROAD GROUPS:
INTERMEDIATE CUTSThinnings, cleanings
SALVAGE/PROTECTION
Clearcut-usually INTOLERANTtrees regenerated-create or promote even-aged stands-best with light seeded spp.-trees are overmatureBE CAREFUL:-Can promote shrubs-can overexpose sensitivesites -slash can impair regeneration.-erosion on steep slopes
CLEARCUTS
In strips…..
or patches:
Jack pine clearcutin Manitoba tomimic natural firepattern
Coppice
You are ASEXUALLYreproducing the forest: stump sprouts
Seed TreeThe trees you leave as seed sources should represent the species you want and are the‘best’ there….
What are the dangers to this process?
Shortleaf seed tree (15 per acre)
SHELTERWOOD Preparatory cuts
These may be one or several light cuts to improve the vigor and wind firmness of potential leave-trees to prepare for the next cuttings. Establishment, regeneration or seeding cut Establishment, regeneration or seeding cut This cutting, which may be the first cutting in some unmanaged stands, is to provide growing space for establishing regeneration while maintaining shelter for developing seedlings. Trees chosen to be retained after this cut should be vigorous and wind firm.
Overstory removal cut(s) Once regeneration is established and stocking is acceptable, removal of the sheltering overstory is a common option. Alternatively, all or some of the sheltering residual overstory can be permanently or temporarily reserved from future cutting to satisfy management objectives.
SHELTERWOOD
Shelterwood on Douglas fir in West (note slope of land)
SELECTIONsingle tree
Usually this and group are for TOLERANT trees and uneven-aged stand
SELECTIONsingle tree
Single tree selection : red spruce,hemlock, and balsam fir
SELECTIONgroup
Group selection: old growthspruce fir forest
INTERMEDIATE CUTSTreatment of stand during part of the rotation not includedin regeneration period….
Intermediate cuts are used for: -improve existing stand -regulate growth -provision for early financial returns
If regulate growth then called thinningsIf regulate species composition: young stands: release cuttings
old stands: improvement cutsIf take branches off: pruning
INTERMEDIATE CUTS
Many types of thinnings:
Low (German)Crown (French)SelectionGeometricFree
CROWN CLASSIFICATION
Low ThinTrees are removed from thelower crown classes
Mimics natural mortality
You can work in a range ofThinnings:
A-B thin without risk ofreducing wood production
C-D stimulate growth ofremaining trees (not just salvage)
CROWN THINRemove trees in middle andupper crown classes
Most trees cut are Codominantbut can take out interferingIntermediates or Dominants
Crown thinning favors nearly thesame trees as Low thins but removes a few strong competitors rather than eliminatethe weak (As Low thin does)
Crown thin is more flexible butdemands greater expertise…
SELECTION THIN
-Dominant trees are removed to stimulate lower crown classes-Vigorous trees favored in Crown and Low are the very ones likely to be cut here-Be careful: limited use, could become High grading!
MECHANICAL THIN
Aspen stand in which 5 meter wide strips are removed to thin…
PRUNING
Very expensive and intensive BUT incertain circumstances you could get moremoney for the wood (no knots)
RELEASE CUTS/TREATMENTDone when stand is young to remove species not desired…..
Pine stand above – releasingpines by using brush saw onundesirable species- the final resultis the bottom picture
IMPROVEMENT CUTS
BEFORE (LEFT) and AFTER (RIGHT) of HARDWOOD STANDIn Mississippi- get rid of poorly formed species or undesirable species and shrubs…