Module 4.) Site Assessment Flashcards
disruptions to a terrestrial site, community, or ecosystem that alters the physical environment.
Land disturbances
a topographic alteration to the surface of the ground.
Grade changes
actions, events, or changes that have taken place on a site.
Land-use history
study of the properties, distribution, and effects of water on the Earth’s surface, underground, and in the atmosphere.
Hydrology
the force on a tree or structure resulting from the impact of wind.
Wind load
the speed of wind.
Wind velocity
wind resistance.
Drag
any form of water that falls to the Earth’s surface, such as rain, snow, or sleet.
Precipitation
uprooting and overthrowing of a tree caused by wind.
Windthrow
exposure to the forces of wind.
Wind exposure
the tree or trees in a stand that are typically larger in height (taller), diameter, and crown spread than all the adjacent trees.
Dominant (trees in a stand)
a group of trees in a wooded setting.
Forest stands
more than one tree sharing dominance in a stand of trees.
Codominant (trees in a stand)
understory trees in a stand or forest with growth somewhat restricted by larger nearby trees.
Subdominant (trees in a stand)
understory trees in a stand or forest with growth severely restricted by competing nearby trees.
Suppressed (tree in a stand)
a tree on the edge of a stand, growing under conditions of light and exposure different from those prevailing within the stand.
Edge tree
a tree within a stand of trees, protected from wind exposure.
Interior tree
the land and water features of an area, including changes in elevation.
Topography
the vertical extent of soil present below ground.
Soil depth
compression of the soil, often as a result of vehicle or heavy-equipment traffic, that breaks down soil aggregates and reduces soil volume and total pore space, especially macropore space.
Soil compaction
Four considerations in site disturbance and changes
Altered wind patterns
Altered levels of sun exposure
Changed soil moisture
Damaged root systems
True/False
Most tree failures occur during normal weather.
False
True/False
A wind rose graph can be used to model regional or local wind patterns.
True
True/False
Trees with less foliage have more drag due to the wind’s direct contact with the major scaffold branches.
False
True/False
Shallow root systems are associated with saturated soils or overirrigated landscapes.
True
True/False
In general, trees with a deep root system are more prone to failure than those with a shallow root system.
False
True/False
A soil probe can be used to determine soil depth and penetrability.
True
True/False
Usually, soils at the top of a slope will be well-drained, and those at the bottom of the slope will be wetter, possibly waterlogged.
True
True/False
The amount of soil volume needed to sustain and support a tree depends on tree species, size, soil characteristics, and climate.
True
Although __________ trees may be well adapted to the prevailing winds as a result of continuous exposure, __________ trees that have been abruptly exposed may have a higher likelihood of failure.
edge
interior
Heavy equipment can cause soil __________, often crushing tree roots or negatively impacting soil structure.
compaction
As a general rule, if one or more large __________ have been severed within a distance equal to three times the trunk diameter, an assessor should look for new root growth or root decay to assess whether the tree has sufficient support.
structural roots
Trees are more susceptible to __________ when the soil is saturated, particularly if the tree is shallow-rooted or the soil is shallow.
windthrow
All other factors being equal, a lone tree may be more prone to failure than a tree in a forest stand because
A) a lone tree would have a more restricted root system
B) a forest stand will provide some protection from wind exposure
C) lone trees tend not to have many branches for damping forces
D) all of the above
B) a forest stand will provide some protection from wind exposure
Wind speeds can be variable depending on
A) height above the ground
B) structures that create a tunnel effect
C) the effects of topography in the area
D) all of the above
D) all of the above
Trees located at the bottom of a steep slope are more likely to
A) experience thinner soils than trees located at the top of the slope
B) fail due to high winds than trees located at the top of the slope
C) fail uphill if basal decay is the cause of failure than trees located at the top of the slope
D) become unstable due to wetter soil than trees located at the top of the slope
D) become unstable due to wetter soil than trees located at the top of the slope
