Urban Forestry Flashcards
weak, narrow branch attachments with 2 equal diameter branches or stems often fail because of
bark inclusions
T/F placement of face cut and hinge will control the direction of the tree falling
true
large and low branches should be pruned early in life of tree because?
wait to long and large wounds will never seal over
series of smaller cuts will be easier for tree to manage
smaller branches means lot less work to cut safely and dispose of material
critical minimum root plate protection zone for trees in Alberta is?
12-15 times the DBH of the tree
tree defects and structural pruning technique
codom stems - choose central leader, prune competing stems to subordinate them
unbalanced canopy - use thinning or heading cuts to make crown proportionate
large low branches - prune early in life of tree
included bark - subordinate the less dominant branch
T/F according to Alberta OHS workers felling trees must use wedges to aid in intended direction of fall
true
young urban forest tree can be pruned how many times in the first 15 years in order to develop strong, sustainable structure?
as many as 5 times
discoveries of nesting holes in a tree being inspected for safety indicates what?
decay is present
when felling a tree, best angle of escape is?
45 degrees opposite of fall
when inspecting sites for electrical hazards to tree care operations, potential hazards are?
chain link fence under transmission or distribution line
guy wire on power pole
communication cables
power poles
between 1991 - 2016, tree workers are killed on average every how many days?
2 - 5 days
most common injury area to a chainsaw operator is?
left thigh
biggest reason arborists and forestry workers report fewer injuries compared to casual operators is due to?
professionals have more skill at operating chainsaws
4 main safety features of chainsaws are?
chain brake, throttle interlock, wrist guard, chain catch pin
first step in effective tree felling plan is?
inspect for hazards
bore cuts are initiated with which part of chainsaw?
bottom tip of bar
making use of strongest part of holding wood, hinge length shouldn’t be more than?
80% the diameter of tree
hinge thickness is no more than?
10 - 15% of the diameter
what are saw dogs?
spikes used to pivot the chainsaw into logs or tree being cut
3 types of chippers are?
rotary drum, disc knife and mechanical drum
5 step felling plan?
check for hazards
determine height and lean
escape route
notch and hinge
perform back cut
2 ways electricity harms tree workers?
direct and indirect contact
dynamic non-invasive tree support systems
cobra cabling
prior to planting a tree that’s been in a container too long to better ensure its survival, you would?
slice an inch off the rootball from top to bottom on 4 sides with sharp spade or pruning saw
root pruning results in better quality tree because?
root pruning causes denser root systems and more fibrous roots
benefits of mulching around trees?
reduced soil moisture loss and temperature fluctuations
reduced weed competition and soil compaction
reduced stem damage due to lawn maintenance and weed whipping