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(LTI) Tips for Using the Latest Technology for Timber Cruising

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(LTI) Tips for Using the Latest Technology for Timber Cruising Laser Technology, Inc. (LTI) (http://www.lasertech.com) Tips for Using the Latest Technology for Timber Cruising Timber Measurements Society - 2010 Bill Carr June 9, 1958 I began my timber cruising career as a GS-3 employee ($3,495 per annum) with the U.S. Forest Service, NE Forest Experiment Station ($891.14 gross pay for 3 months) Early Traditional Cruising Tools Biltmore stick and Abney level 1992 Tree Height Significance Tree height is used for volume, value and growth & yield determination. Volume (cf) of immature Douglas fir in British Columbia: log V = 2.85805 + 1.739925 log D + 1.133187 log H So calling a 20" DBH tree that's 120 ft. tall (5% error in height) results in a 5.5% error in volume. Measure from a point perpendicular to the lean – tangent solution Timber cruisers have been trained to measure heights from a location that is perpendicular to the lean. This would solve most of the problem except that topography and perception often prevents an accurate measurement. The tree may appear to lean to the right or left but really quarters to you or away from you. Height error when lean is towards the cruiser Tree Height = 100 feet Degree of lean Distance from base of tree 50 feet 100 feet 1 degree 3.6% 1.8% 2 degrees 7.5% 3.6% 5 degrees 33.3% 9.5% 10 degrees 53.2% 21.0% 15 degrees 107.3% 34.9% Leaning Tree Height Improper technique Tangent Height Distance Leaning Tree Height Proper technique Tangent Height Distance Impulse 200 (1996) Main Features: Range: +0.1 foot To a tree 450 to 3,600 feet Tilt accuracy +0.1 degree Tree Heights 3- shot tangent solution Impulse 200 Evaluation by the U.S. Service Forest TruPulse 200 / 200B (2004) Accuracy: Distance + 1 ft ; Inclination + 0.25 degrees Range: 0 to 3,280 ft (6,560 ft to reflective target) Operating Modes: Slope, horizontal and vertical distance, 3-point height routine, closest, farthest and continuous target acquisition The most accurate method to measure tree heights is with a laser instrument developed before 2007. First, determine the horizontal distance (HD) to the central axis of the tree under the top. HD Then shoot the angle to the base of the tree to determine the vertical distance from the horizontal to the base of the tree. Vertical Distance to BASE Then shoot the angle to the top of the tree to determine the Vertical Distance vertical distance to from the TOP horizontal to the top of the tree. The next push of the firing button solves for tree height. HEIGHT The Next Best Procedure Place a reflector directly under the top of the tree, at the parallel to the base. With the electronic filter turned ON, scan back and forth until the laser locks onto the reflector, fire the Height laser again to get the base angle and then shoot the angle to the top of the tree. Sine-based tree height measurement Tree height = a + a´ = [(sin A) × c] The sine method + [(sin A´) × c´] requires a physical target-not just an angle to the top and base of the tree!! c a A b A´ c´ a´ Cosine-based tree height measurement Tree height = a = b2+c2-2bcCosA The cosine method requires a range c measurement (b and c) and an angle (A) to the top and base of the tree!! a Accurate if the tree leans directly towards or away A from you. b The “Leaning Pine” was a recognizable symbol of a forestry school in the Northeast but also a mensuration course challenge. Tilted Tree Hypsometry by L.R. Grosenbaugh Two Observation Points per Tree are Required TruPulse 360 / 360B (2007) Main Features: Range: Accuracy + 1 foot Maximum range 3,280 feet to typical target (6,560 feet to a reflective target Inclination accuracy: + 0.25 degrees Azimuth accuracy: + 1 degree Height determination: 3-shot tangent solution for height determination 2-shot coordinate solution for height, displacement and length determination Using a TruPulse 360 to Measure Displacement of Top from Base, Vertical Height, Length of Tree Bole and Azimuth from Tree Top to Base The solution requires two shots and X, Y, Z is accurate regardless of which way the tree Leans. X, Y, Z x, y, z TruPulse 360 / 360B VD SD Shot 2 Missing Line (ML) Routine INC HD (AZ) x, y, z Shot 1 Missing Line HD Solution Missing Line VD Solution Missing Line SD Solution TruPulse, Reflector and Foliage Filter Battery Duration • AA: Approximately 7,500 measurements • (6,000 with Bluetooth enabled) • CRV3: Approximately 15,000 measurements • (12,000 with Bluetooth enabled) Crown Width Missing Line Mode – Shoot a branch on one side of the crown and then one on the other. Immediately the horizontal distance between the two points is displayed. Determine Tree Spacing Angle Gauges Angle Gauge - 1948 Prism - 1948 Spiegelrelaskop - 1950 Dendrometers Barr & Stroud - 1945 Criterion - 1992 Criterion RD 1000 - Electronic Angle Gauge (2005) BAF range: 1 to 127 ft2/acre (0.3 to 29.1 M2 / Hectare) Solid Bar vs. Gap Bar Illumination Brightness Adjustment BAF 20 Mode Measurement bar length adjusted for slope Point Sampling Trees/acre = BAF / 0.005454 x DBH2 Trees/acre = 20 / 0.005454 x 82 = 57.3 trees/acre Setting Imperial BAF’s to Tenths • Change measurement unit’s to METRIC • Return to BAF Mode and EDIT in the metric equivalent: – Multiply Imperial BAF by 0.22957 – (example: 17.5 BAF x 0.22957=4.0 metric) IN / OUT Tree Mode Enter DBH either by measuring with the instrument (in DIAMETER mode) or manually Enter horizontal distance from plot center (instrument) to the face of the tree at DBH manually or automatically with LTI laser (Since the Limiting Distance is to the face of the tree at DBH the Plot Radius Factor has been adjusted by the radius at DBH. So the PRF has been reduced by one-half the DBH, expressed in feet (0.5/12 = 0.04167). Press ENTER and the LCD and HUD will indicate if the tree is “IN” or “OUT” of the plot DIAMETER Mode LCD HUD Display shows DIAMETER when the trigger is released Diameter resolution With Magnifier Without Magnifier + ¼ inch at 80 feet + 5/8 inch at 80 feet + 1/8 inch at 40 feet + 3/8 inch at 40 feet Computation of Diameter S= D2L D/2 L+D S D/2 L D/2 2 2 2 D= S + S (S +4L ) SINCE: 4L2 >> S2 2L D __ (S2 + 2SL) / 2L D ___S( 1 + S/2L) Diameter (D) Range / Distance Distance to Face-of-Tree W/O Magnifier With Magnifier @ Point of Measurement Min. D Max. D Min. D Max. D 20’ 2.3” 27.7” 1.0” 11.8” 30’ 3.4” 41.5” 1.4” 17.3” 40’ 4.5” 55.3” 1.9” 22.8” 50’ 5.7” 69.1” 2.3” 28.4” 60’ 6.8” 83.0” 2.8” 33.0” 70’ 7.9” 96.8” 3.2” 39.5” 80’ 9.1” 110.7” 3.7” 45.1” 90’ 10.2” 124.5” 4.2” 50.7” 100’ 11.4” 138.3” 4.6” 56.3” 110’ 12.5” 152.1” 5.1” 61.9” 120’ 13.6” 166.0” 5.5” 67.5” HEIGHT / DIAMETER Mode Determining Tree Cull Percentage Approximate Percent of Tree Volume by 16-Foot Logs Scribner Dec. C or Cubic Reference Log Height Height 1 2 3 4 5 6 7 8 9 10 9 – 25 1 100 26 – 42 2 68 32 43 – 59 3 47 36 17 60 – 75 4 38 29 22 11 76 – 92 5 33 27 20 14 6 93 – 108 6 28 25 20 16 7 4 109 – 125 7 26 23 19 17 8 4 3 126 – 141 8 24 21 18 15 10 6 4 2 142 – 158 9 19 17 15 14 13 10 6 4 2 159 – 174 10 19 17 15 14 13 9 6 4 2 1 i.e.-If a tree is 86 feet to a 6.0-inch top and has a fire scar in the 1st log requiring a 2- foot deduction, the tree is 4 % cull. Accessories for the Impulse Lasers MapStar Compass Module MapStar Angle Encoder Accuracy: +0.3° Accuracy: +0.05° MapStar Compass Field Test and Overview: by Robert Schroeter, Jack Fetterman and Robert Pierle Conclusion of Field Test Integrated Set-up for Tree Modeling with a TruPulse Laser Inventory Plot - Jilove, Czech Republic European Countries Using LTI Products for Forest Inventory • NFI – Ireland • Czech Republic • Slovakia • Iceland • Hungary • Ukraine • Russia • Most Forest Reserves Throughout Europe Happy Trails! 28 Year Old Eastern White Pine (Pinus strobus) Duroflora Company Near Piracicaba, Brazil 1-year old Eucalyptus grandis stand 2-year old E. grandis stand 3-year old stand of E. grandis 21 –year old E. grandis stand 10-year old Pinus radiata stand near Conception, Chile 5 1/2 –inch pen Inventory Plot - Pinus radiata Cooma, New South Wales, Australia Pinus radiata Stands Near Ballarat, Victoria, Australia 25-year old stand 40-year old stand 55 year old Redwood (S. sempervirens) stand – Ballarat, Australia 25 Year Old Sitka Spruce Plantation - Moffett, Scotland Forest Expo – Soustons, France Area Near Schmallenberg, Germany Demonstration Plot - Ministry of Forestry Hdqts.Fontainelleau, France (Napoleon’s Estate) Traditional Surveying Tools- Mid 1950’s Staff compass, chain, Abney level, and Reinhardt Redy Mapper Skull Creek Timber Sale (113 MMBF) Preparation - 1965 Traditional Cruising Tools Used from the mid 1960’s Until Early 1990’s Introduced the First Laser Designed for Forestry (1992) Criterion 400 Ceased production Features: about 10 years ago.
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