MONTANA VEGETATION PROTOCOL
Updated 11/2009
Systematic vegetation and nest vegetation plots are used to determine habitat features
associated with nest success and non-use sites. Some of the measurements collected are
subjective; however, it is important to be as CONSISTENT as possible. If you are unsure how
to determine a particular measurement, look it up in this protocol (99% of FAQs are in
here!!!), if you are still unclear PLEASE ask a supervisor (they are your friend), DO NOT
guess.
NEVER GUESS IN RIGOROUS DATA COLLECTION, THIS IS WHY WE HAVE
PROTOCOLS!!!
This protocol is organized in sections:
1. Setting Up Systematic Vegetation, Open-Cup Vegetation, and Cavity-Nest Vegetation Plots
2. Top Of The Datasheet - Data To Collect
3. Additional Measurements Taken For Cavity Nesting Birds
4. Measuring Ground Cover
5. Stem Counts
6. Tree Counts
7. Reading The Densiometer
8. Using a Clinometer
You will need the following equipment when carrying out vegetation surveys:
(This equipment will be given to each of you by your supervisors. Make sure you (the plot
owner) have all of the following with you every day for this portion of the project)
1. vegetation protocol
2. systematic, open-cup, and cavity nest data sheets
3. tree ID guide
4. meter stick
5. small plastic ruler
6. densiometer
7. clinometer
8. compass
9. ropes marked at 5 m and 11.3 m
10. clipboard
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1. SETTING UP SYSTEMATIC VEGETATION, OPEN-CUP VEGETATION, AND
CATITY-NEST VEGETATION PLOTS
Systematic vegetation plots are used to describe general vegetation characteristics of the study
plots, differences in vegetation composition along the topographical gradient, and differences in
vegetation between nesting and non-use sites.
Systematic vegetation plots are at flagged locations that are within a 25m x 50m grid.
Refer to maps or GPS to find points, if needed.
Transect R2
Transect R1
Station 1
Center transect = X
Transect L1
Transect L2
Station 2-L1
FIGURE 1: SYSTEMATIC VEGETATION PLOT LOCATIONS RELATIVE TO
POSITION ON LANDSCAPE
To begin setting-up a vegetation plot, establish four quadrants by placing ropes parallel and
perpendicular to the slope centered on the nest (this should never be done while a nest is still
active). For the systematic vegetation surveys, the center of the plot should be the semipermanently-placed systematic survey marker (Each marker is labeled according to a grid; see
figure above). For cavity nesters, place ropes so that cavity opening is at the center (45 degrees)
of one 90-degree quadrant of the vegetation plot. Measurements are taken within two circles
centered at the nest or survey stake: 1) a 5 meter radius is used to count shrub and sapling stems
and measure ground cover, and 2) an 11.3 m radius plot is used to count the number of trees.
The 5 m plot is within and centered on the same point as the 11.3 m plot.
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FIGURE 2: 5-METER VEGETATION PLOTS (11.3m IS A CONTINUATION OF 5m.)
Downhill
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2
3
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2. TOP OF THE DATASHEET DATA TO COLLECT (some of these categories are missing
for systematic veg because they have to do with the nest location, etc)
SUBSTRATE 1 & 2 - plant species substrate the nest is in. Use plant species listed.
NEVER use >ground=. For ground nests, record the most important feature
within 30 cm of the nest (usually a plant, but occasionally rocks, logs, etc..). Use
GRASS if nest is under grass tussock of unidentified species. Leave SUBSTR. 2
blank unless there is more than one substrate supporting the nest.
TABLE 2: Possible Substrate and Concealment Codes:
DFIR
LPINE
PPINE
SPRUCE
ASPEN
RMJUNIP
JUNIPER
WILLOW
MAPLE
BUFFB
SNOWB
THIMB
RASPB
SERVB
Douglas Fir
Lodgepole Pine
Ponderosa Pine
Englemann’s Spruce
Aspen
Rocky Mountain Juniper
Common Juniper
Willow (all species)
Mountain Maple
Buffaloberry
Snowberry
Thimbleberry
Raspberry
Saskatoon Serviceberry
DFSNAG
LPSNAG
PSNAG
SSNAG
ASNAG
ROSE
DOGWOOD
CURRANT
ALDER
GRASS
FORB
LOG
ROCK
OTHER
Douglas Fir Snag
Lodgepole Pine Snag
Ponderosa Pine Snag
Spruce Snag
Aspen Snag
Rose
Dogwood
Currant
Alder
Grass
Forb
Log
Rock
Anything not listed
CONCEALMENT 1 & 2 - the plant species or other substrates that are primarily
responsible for concealing the nest. Use the same codes as for SUBSTRATE.
Leave CONCEAL 2 blank if only one type of substrate conceals the nest.
NEST HEIGHT - Measure nest height in meters. Do not estimate this value. Use any
reliable technique (clinometer, meter stick, etc..)
Note: write in 0 (zero) for ground nests.
ORIENTATION - Orientation of the nest relative to the substrate in degrees. For open
nesters, stand at the central stem OF THE NEST SUBSTRATE, face the nest and
take a compass reading. This reading is analogous to the direction the bird leaves
the nest. For plants with no central stem, use the center point of the plant as a
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reference point. If an open nest is in the exact center of the plant and has no
orientation, write “999” here to make it clear that you didn=t forget to record the
data (do not put 0 for no orientation).
* For cavity-nesters, take a compass reading in the direction that the bird would
be looking if it were looking straight out the nest hole.
SUBSTRATE HEIGHT - Measured height in meters of plant or other substrate recorded
under SUBSTRATE. Measure using same methods under NEST HEIGHT above.
DIAMETER AT BREAST HEIGHT (DBH) - Measured Diameter (cm) at Breast
Height of SUBSTRATE. If the substrate is not breast high, put “999” in box.
DISTANCE FROM STEM - Distance from the central axis of the plant to the center of
the nest in cm. If the plant has no single central stem then select a central axis
that represents the center of the plant. If the nest is on the ground, then record a
distance to the object listed under PLANT SPECIES if it is less than 30 cm from
the nest. Leave blank if nest is more than 30 cm from a plant. When making this
measurement from high nests, visualize a line extending down from the nest to the
ground, and then measure from this point to central stem.
DISTANCE OF NEST FROM FOLIAGE EDGE - Record the horizontal distance
from the nest to the nearest outer edge of the foliage (horizontal distance at the
same height as the nest). Note that the outer edge of foliage can actually be in a
different plant or species in areas of thick vegetation. Record zero (0) for cavity
nests and nests attached to the trunks of trees at a level below the nest tree’s
canopy. Use the same measuring technique described under DISTANCE FROM
STEM above for high nests.
# SUPPORT BRANCHES - Number of branches supporting an above ground nest.
This includes both twigs and larger branches. Only branches that are at least
partially under the nest, or that the nest is woven into should be counted. Don’t
count vertical trunks that may provide lateral support. If a branch or stem is
completely vertical it should not be counted. If a stem adjacent to the nest is not
completely vertical then some portion is probably under the nest, and it should be
counted (see examples in figure 3, below).
FIGURE 3. COUNTING NUMBER OF SUPPORT BRANCHES
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DIAMETER OF SUPPORT BRANCHES - Average diameter of supporting branches
or twigs in cm. Note that for high nests this will often be a visual estimate. It is
easiest to base it on your own finger diameters for comparison.
% OVERHEAD COVER - Overhead cover for low nests. Percent of the nest obscured
by vegetation from 1m over the nest looking down. Imagine a 25cm diameter
circle around the nest, and a 1-meter high vertical cone from your eye to the nest
(see figure 4 below). Estimate % cover of the circle in this cone.
FIGURE 4: ESTIMATING OVERHEAD COVER
% SIDE COVER - Side cover for low nests. Percent of nest obscured by vegetation
from 1 meter N, S, E, W of nest at nest height. Record for nests above your head
when a reasonable estimate is possible, otherwise ignore. Imagine a 25 cm
diameter circle around the nest, and a 1 meter long cone extending back from the
nest to your eye (see figure 5, below).
FIGURE 5: ESTIMATING SIDE COVER
Note: Both overhead and side cover should be measured even if nest itself has been
destroyed. If nest is too high to accurately estimate overhead or side cover than skip.
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TREE HEALTH - L=Live, MA=Mostly Alive, MD=Mostly Dead, D=Dead.
DISTANCE TO MIDDEN - Distance to the nearest red squirrel middens (cone piles).
Record distance to both nearest MAIN midden (large: with many cone scales) and
nearest SATELLITE midden (smaller midden surrounding main middens) within
25 m of nest. If no middens are within 25 m of the nest, record A>25 m@.
NEST MEASUREMENTS - ID=Inside diameter, IH=Inside height, OD=Outside
diameter, OH=Outside height. All measurements in millimeters. These
measurements are only taken on nests that can be easily reached. Meter sticks are
often too large to measure nests. Either carry a small ruler, or use a finger or twig
to measure and then place that against a meter stick to get mm.
GPS LOCATION – record the Waypoint name and the Lat/Long of the station marker.
STATION/DIR. STN TO NEST/DIST STN – these should be copied from the nest
card for this nest.
PLOT ASPECT - The direction the 5 m (not the 11.3m) vegetation plot faces in degrees.
From the top of the 5 m vegetation plot face downhill (the direction water would
flow) and take a compass reading in degrees. For cavity nests also measure
aspect at 5 m vegetation uphill from nest (not at top of 11.3 m circle; should be
cavity orientation minus 45 degrees).
SLOPE - Measure the slope across the 5 m plot from the top to the bottom of the plot in
degrees (LEFT HAND SCALE OF CLINOMETER). Be sure to choose an
object that is at the same eye level when making this measurement. See AUsing a
Clinometer at end of this handout. For cavity nests also measure slope across a 5
m radius circle centered on the nest tree (not across the 11.3 m circle).
ASPEN PATCH CONTEXT – Record one of two descriptions in this box: Conifer or
Grassland. ‘Conifer’ refers aspen patches surrounded primarily by conifers
(>50%), and ‘Grassland’ refers to aspen patches surrounded primarily by
grassland (>50%).
HIGH CANOPY - Percent canopy cover above 5 m in height. This measure is intended
to measure the upper canopy, not lower canopy layers. Stand at/under the nest
(center of the plot for systematic veg) and take 4 densiometer readings, turning
90 between readings. (leave the avg blank) This measure can be difficult if there
is a lot of low vegetation. We want an estimate of high canopy cover so try the
following methods to avoid low vegetation:
1) Step away from the nest to a more open area that is representative of the high canopy
above the nest.
2) If there is relatively little low vegetation you can sometimes ignore it when counting
densiometer dots covered and uncovered.
3) If low cover is too continuous for a good densiometer reading then make an ocular
estimate of cover above 5 m.
** See section 8 “Reading a Densiometer” at the back of this protocol
TOTAL CANOPY - Percent total canopy closure measured with a densiometer. Stand
at/under the nest (center of the plot for systematic veg) and take 4 densiometer
readings, turning 90 between readings (leave the avg blank). This variable is
intended to measure total canopy cover, including high and sub-canopy cover
Note that it is easier to measure HIGH CANOPY and TOTAL CANOPY at the
same time, noting numbers for each quadrant before moving on to the next.
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DOMINANT SHRUB SPECIES - List the plant species that is most prevalent (i.e.,
dominant) in making up the “shrub” cover that you estimate in the ground cover
section (section 4). Use the substrate codes for this (section 2). If two species are
equal, then list both. Definition of “shrub” – woody plant <1.5 m in height (not
<0.5 m like the ground cover section so we can include young aspen, willow, and
maple).
DOMINANT CANOPY SPP 1 - Dominant Plant Species In Canopy C This is a measure
of the plant species that dominates the high canopy within the 11.3m plot. Use
plant codes listed in nest Substrate section above. Record species that account for
at least 40% of the high canopy present. Leave blank if no single plant species
represents > 40% of the high canopy present.
% COV: Percent Of Dominant Canopy Species C Percent of high canopy occupied by
DOMINANT PLANT SPECIES IN CANOPY. Must be > 40%.
CAN. SPP. 2: Co-Dominant Plant Species In Canopy C Use this variable when there are
2 plant species that each represent > 40% of the high canopy present. Leave
blank if there is not a second plant species that represents > 40% of the high
canopy that is present.
% COV: Percent Of Co-Dominant Canopy Species C percent of high canopy occupied
by CO-DOMINANT CANOPY SPECIES.
AVERAGE TOP CANOPY HEIGHT - Choose a point in the canopy that represents
the typical height of the top of the canopy within 11.3 m of the center of the
vegetation plot (ignore lone trees that emerge above the main canopy when taking
this measure). Measure the height of this point with a clinometer.
LITTER DEPTH - In each of the 5 m vegetation plots we also measure the depth of
organic litter, using a ruler to dig a small hole down to where individual leaf parts
are no longer visible (leaf veins usually decompose last). We are interested in the
depth of leaf litter and partially decomposed organic matter that accumulates on
top of the mineral soil. Organic litter depth (in mm) should be measured across
the center of the plot parallel and perpendicular to the slope of the plot. Measures
should be made at 12 points as shown in the figure below in figure 6. If any of
these 12 points land on a log or a rock, or in an area that has an unusual
accumulation of litter due to wind or squirrel activity, move the meter stick
slightly to a location where you are measuring more typical litter depth.
FIGURE 6: LOCATIONS FOR LITTER DEPTH MEASUREMENTS
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3. ADDITIONAL MEASUREMENTS TAKEN FOR CAVITY NESTING BIRDS
For cavity nesting species, some of the measurements change. Much of the nest data is
deleted, and instead, we describe the tree that the cavity nester is in. The following are
measurements taken only for cavity nesters:
CAVITY AGE - New - New cavities have yellowish unweathered wood at the cavity
entrance, and sometimes wood chips at the base of the nest tree , Expanded, Old,
or Natural (a crack or natural hollow knot).
% BARK COVERAGE - Estimated % of snag covered with bark.
TOP BROKEN - Yes/No
TOTAL NUMBER OF CAVITIES - SMALL - PYNU and RBNU size
TOTAL NUMBER OF CAVITIES - MEDIUM - WISA and RNSA size
TOTAL NUMBER OF CAVITIES - LARGE – RSFL and PIWO size
OVERALL CRYPT - Rate the overall cryptic-ness of the nest on a scale of 0 - 4.
Consider vegetative concealment, bark hiding the nest, dark patches that
camouflage the nest, etc. (0 = no concealment, 4 = extremely cryptic)
OBSCURED BY BRANCHES/TREE - How well is the nest concealed by vegetation in
a 90 degree arc from 45 degrees on either side of the cavity at 10 meters from the
nest tree. Rate on a scale of 0 - 4. (0 = no concealment, 4 = extremely
concealed)
IN KNOT - Is the cavity located in a knot or broken off branch (Yes/No)
UNDER KNOT - Is the cavity located under a knot or branch (Yes/No)
DARK AREA - Is the cavity in a dark patch on the tree (Yes/No)
4. MEASURING GROUND COVER
For each of the 4 quadrants in the 5 m plot, first make an ocular estimate of the percent of the
ground covered by total green vegetation from ground level up to 50 cm above ground
(%Green). Then for each class of vegetation (grass, forb, shrub, aspen) estimate a percent value
independent of all other vegetation types (i.e. as if other vegetation types were absent). % grass,
forb, shrub and aspen can sum to more than 100% because of vertical stratification of plant
layers. However, no single category of vegetative cover should be greater than the value for
%GREEN.
FIGURE 8: GROUND COVER MEASUREMENTS IN THE 5m PLOT
Ground cover measurements in the 5m vegetation
plot. Notice that there are two types of ground
cover that affect cover estimation rules: tall sparse
cover that can overlap with low cover types, and
low dense cover that cannot overlap with other low
cover types (see figure to left). Percent cover in
high and low cover types can sum to more than
100%, but low cover types (low grass, bare
ground, moss, low dense shrubby things, leaf litter,
logs, etc..) alone must sum to 100%.
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Ground cover categories are as follows:
% ALL GREEN COVER - percentage of ground covered by green vegetation that is
below 50 cm in height (Will not be over 100%)
% GRASS COVER – live/green grass below 50 cm in height.
% SHRUB COVER - below 50 cm. Perennials are considered shrubs, and include
plants that were too small to make the stem count. Basically any foliage for
woody stemmed plants that is less than 50 cm in height.
% FORB COVER - below 50 cm. Annuals are considered forbs (green stems +
Oregon Grape and Kinnikinik).
% FERN COVER - below 50 cm.
{
These 4
added up
can equal
more than
% Green
% DOWNED LOGS - percent of ground covered by downed logs (logs >12 cm
diameter
% BARE GROUND - percent open ground not covered by leaf litter; also includes
open water.
% LEAF LITTER COVER - percent of ground covered by leaf litter. This value
should be independent of taller, sparser vegetation (litter + tall sparse
vegetation can sum to more than 100%), but is dependent on low dense
vegetation (litter + bare ground + log + low dense vegetation (aka grass)
must sum to 100%). See below.
AN EXAMPLE OF GROUND COVER MEASUREMENTS:
% green
% grass % forb % shrub % fern
% log % bare
60
30
10
10
20
20
25
% litter
25
Percent green consists of grass, forb, shrub, and fern (basically the % of ground cover that’s
green).
Percent grass, forb, shrub, and fern must sum to at least %Green, but that summation may be
more than % Green due to stratification of veg types (this means that this summation may be
over 100% and that’s fine). However, no single value of grass, forb, shrub, or fern may be more
than % Green value.
So what about percent log, bare, and litter you may ask? Well, percent log, bare, litter and
grass (because most grass is low dense vegetation) must always sum to 100%.
Lastly, check and then recheck to make sure you and your partner have done this correctly so
you don’t have to redo any plots.
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5. STEM COUNTS
Stem counts are conducted within the 5-m radius plot centered at the nest or the systematic
survey point.
There are columns for some stem species: Seed, Ram, and Brow. We are measuring new
recruitment (this year’s new plants) by counting seedlings and ramets. We are also looking at
the browsing pressure by counting how many stems have been browsed in the last year.
Seed: Count the number of seedlings for each species found within the 5 m radius plot. This is
done for every species excluding Aspen. A seedling comes from a germinated seed this year, not
a runner, that has a green, soft stem and cotyledons (cotyledons can fall off later in the season, in
which case the main distinguishing feature is a green, non-woody stem).
Ram: Count the number of ramets for each species found within the 5 m radius plot. This is
done for Aspen only. Ramets are produced by underground runners (i.e., rhizomes) from a
mother tree. They also have a green, soft stem but do not have cotyledons.
Brow: Total number of stems in that size category that have been browsed this year or in
previous years. This number must be equal to or less than Total for that size category. In other
words, Brow < ½ m is how many stems out of the total < ½ m category that have been browsed.
Browsed- If the stem looks freshly chewed (white/yellowish looking at the top of the
stem) or has leaves that have obviously been eaten off. Also, if top of stem is grey or
brown (these were probably browsed other years).
Not Browsed – If the plant looks fully intact and has all of it’s leaves, then it is not
browsed.
Stem Count size categories:
Conifers:
Deciduous:
Seed- seedlings
Seed- seedlings
<1/2- Shorter than ½ m tall
Ram- ramets
½- 3- Between ½ and 3 m tall
<2 ½ - (cm) diameter- MUST be taller than ½ m
8-23- (cm) DBH
2 ½ - 8- (cm) diameter- MUST be taller than ½ m
23-38- (cm) DBH
8-23- (cm) DBH
>38- (cm) DBH
>23- (cm) DBH
** if a conifer stem is taller than 3 meters and yet not 8cm in DBH, pick the category it is closest
to. i.e. A doug fir is 6 meters tall and 5cm DBH then put it in the 8-23 category. If a
white fir is 4 m tall and 5 cm DBH then put it in the ½ -3 tall category.
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Deciduous stem counts: Counts of deciduous stems are entered on the data sheet according
to their diameter. The procedure for measuring deciduous plants’ diameters varies by size.
There are four diameter-size categories.
 For the two smallest diameter-size categories (<2½ cm and 2½ – 8cm diameter), measure
diameter at 10cm high (approximately ankle height). Only include stems taller than 0.5
m. A stem is defined as one that originates below 10 cm above ground. For example:
If:



the plant branches in two below 10 cm that
plant should be counted as two (as shown in
the diagram to the right).
the plant branches into two above 10 cm that
plant should be counted as one (as shown in
the diagram to the right).
For the two larger diameter-size categories (8-23 cm and >23 cm), the diameter is
measured at breast height, and stem counts are the same as for smaller (above).
(We count this way because many plant species break into multiple stems fairly close to the
ground. In these situations, it is reasonable to assume that birds respond to stem densities rather
than individual plant numbers. Therefore, in these cases we count vertical stems, not individual
plants.)
Conifer stem counts: Conifer stem counts are recorded slightly differently from deciduous stem
counts. While all deciduous stem counts are recorded in categories of diameter, some conifers
are recorded by height while others are recorded by diameter. In general terms, smaller conifer
trees (i.e., 3 meters or shorter) are recorded by height, and larger conifers (i.e., taller than 3
meters) are recorded by diameter.
 For conifers 3 meters or shorter, record count in either the < ½ m or ½ m - 3m tall
category, as appropriate.
 For conifers taller than 3 meters, measure diameter at breast height and record counts in
the appropriate diameter categories on the data sheet (i.e., 8-23 cm; 23-38 cm; or >38 cm)
 In the rare instance of a conifer that branches into two or more stems use the same
technique for counting as we do above for deciduous trees (i.e., for the two smaller
classes of conifers, follow the technique for smaller deciduous trees; for the larger
classes, follow the technique for larger deciduous trees).
6. TREE COUNTS
The 11.3-meter radius plots are used to count the numbers of trees near the center of the
vegetation plot. Live trees are separated into the size classes given in the table below. Separate
counts should be made for each species of tree in the plot. Snags are counted into three size
categories when larger than 20 cm DBH. (We don't separate snags by species). Note: THE
TREE COUNTS IN THE 11.3 M PLOT INCLUDE THE TREES OF THAT SIZE FROM
THE 5 M PLOT. A system of double marking is helpful. Make dots or hash marks on the Tree
Count section of the vegetation data sheet for the larger trees in the 5 m as you count them.
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TABLE 3: TREE SIZE CLASSES
Live Trees (measure each
species separately)
Snags (combine all
species)
Small trees: 8 - 23 cm DBH
Medium trees: 23 - 38 cm DBH
Large trees: >38 cm DBH
7. READING THE DENSIOMETER
Densiometers are used to measures forest cover. The densiometer is a convex or concave mirror
with a grid etched into it. There are 24 squares in the mirror. Imagine 4 uniformly spaced dots
in each square of the grid, as illustrated (see figure 10, below), and count either the number of
dots covered by vegetation OR the number not covered by vegetation. When percent canopy
cover is high, it is easier to count dots not covered and subtract the total from 96.
When canopy cover is low, it is quicker to count covered dots and record that number. Always
record number of dots covered, not number uncovered. Do not break the squares into 4
imaginary squares and try to decide if each one has greater or less than 50% cover. The 4
squares within a square method introduces bias because individuals tend to decide close calls
more frequently in one direction than another. Deciding whether or not an imaginary dot is
covered is a simple objective decision, and is less susceptible to bias. Avoid counting trunks as
cover when possible, particularly when they make up a substantial portion of the cover. Step
away from the trunk if necessary. Dot numbers will be converted to percent canopy cover (#dots
covered/96*100) for reporting purposes, but field assistants should not do these conversions in
the field.
FIGURE 10: DIAGRAM OF DENSIOMETER SURFACE
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8. USING A CLINOMETER
A clinometer is used to measure the height of objects and slope. It=s based on basic
trigonometry, where you measure two legs of a triangle, and calculate the third, which is height.
Our clinometers have both a percent (right side, used for height) and degree (left side, used for
slope) scales.
When measuring height, pace off between 15 and 25 m from the object of interest (the further the
better). Try to keep the base and top of the object in view. It is best to walk along the slope,
rather than up or down the slope, to do this measurement. Looking through the clinometer with
one eye, and keeping the other eye open, line up the cross hair with the height of the object to be
measured and note the percent (this number will be positive). Then line up the viewing line with
the bottom of the object and note the percent. (This number may be positive, negative or zero
depending on whether or not you are standing below, above or at the same level, respectively, as
the object you are measuring.) If you have a negative number, (i.e. you are standing above the
base of the object you are measuring) ignore the negative sign and add the two numbers together.
If you have a positive number, (i.e. you are standing below the base of the object you are
measuring) subtract the base number from the height number. (This quickly becomes instinctive
once you have done it a number of times.) Measurements should be recorded as both distance
paced from object and % height. For example, 87% x 20 m. Be sure to always write the % sign
so we know which is which. Measurements of over 100% are not accurate and should be redone,
walking farther away from the object the next time.
When measuring slope, be sure to view an object that is at the same height as your own eye
level, not ground level. A bit of flagging tape or a colorful pen attached to a branch at eye height
is good for this purpose. Mark the object, then walk 5 m up or down slope and view that object
through the clinometer. Read slope from the left side of scale. Ignore positive and negative
signs.
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