Adam Dick M.Sc.F. Candidate, University of New Brunswick 2007 Western Mensurationists Meeting June 24-26, 2007 Kelowna, B.C.

Introduction  A Google example: 15 September 2015Adam Dick ~ Western Mensurationists Meeting2

Introduction 15 September 2015Adam Dick ~ Western Mensurationists Meeting3

Introduction 15 September 2015Adam Dick ~ Western Mensurationists Meeting4

Introduction 15 September 2015Adam Dick ~ Western Mensurationists Meeting5

Introduction 15 September 2015Adam Dick ~ Western Mensurationists Meeting6

Introduction 15 September 2015Adam Dick ~ Western Mensurationists Meeting7

Introduction  Photography has been an important tool used by foresters for many years  Satellite/ aerial photography underpins most large scale inventories  What if we could have an in-stand perspective to help interpret collected data?  Assist by making data collection more efficient? 15 September 2015Adam Dick ~ Western Mensurationists Meeting8

15 September 2015Adam Dick ~ Western Mensurationists Meeting9

360- degree photography  Equipment  Digital camera  Tripod  Tripod mount  Ensures nodal point of lens is above rotational axis of tripod  Eliminates parallax errors 15 September 2015Adam Dick ~ Western Mensurationists Meeting10

360- degree photography  Camera mounted vertically  Photo every 15-degrees  24 photos per plot  Ensures adequate overlap between adjacent images  Focus, flash settings the same around plot 15 September 2015Adam Dick ~ Western Mensurationists Meeting11

360- degree photography 15 September 2015Adam Dick ~ Western Mensurationists Meeting12  Software (Panorama Factory v4.5)  Automates stitching process  Automatically corrects barrel distortion, detects focal length

360- degree photography 15 September 2015Adam Dick ~ Western Mensurationists Meeting13

360- degree photography  Unwrap and print out flat stand  Distortion free  Consistent scale 15 September 2015Adam Dick ~ Western Mensurationists Meeting14

 So………  How can we use these photographs? 15 September 2015Adam Dick ~ Western Mensurationists Meeting15

Using photography 15 September 2015Adam Dick ~ Western Mensurationists Meeting16

Spatial tree mapping  To calculate distance to object  Dimension of the tree (or surrogate)  And camera focal length 15 September 2015Adam Dick ~ Western Mensurationists Meeting17

Spatial tree mapping  Calculate azimuth to object 15 September 2015Adam Dick ~ Western Mensurationists Meeting18

Spatial tree mapping  Azimuth of first tree measured used as reference  Could arbitrarily start at zero if only relative position of trees is required 15 September 2015Adam Dick ~ Western Mensurationists Meeting19

Using photography 15 September 2015Adam Dick ~ Western Mensurationists Meeting20

Angle count sampling (ACS)  Bitterlich 1948  “basal area density of a unit area of area can be estimated by counting those trees whose diameter at breast height (dbh) subtended angles appearing larger than the horizontal angle-gauge” (Grosenbaugh 1958) 15 September 2015Adam Dick ~ Western Mensurationists Meeting21

Angle count sampling (ACS)  Using a camera  Decourt, N Utilisation de la photographie pour mesurer les surfaces terriers. Revue forestière française, Vol 8. No.7 pp  Adaptation of Bitterlich to use photographs 15 September 2015Adam Dick ~ Western Mensurationists Meeting22

Angle count sampling (ACS)  Several methods identified to do ACS  Measure width of trees in photograph  Calculate the BAF of each tree  Apply desired BAF constant (e.g. mBAF2) 15 September 2015Adam Dick ~ Western Mensurationists Meeting23

Angle count sampling (ACS)  Calibrate gauge width for photograph  Count trees larger than gauge width 15 September 2015Adam Dick ~ Western Mensurationists Meeting24

Angle count sampling (ACS)  Do as a prism does  Shift the tree at breast height by gauge width  Tree overlaps: in  Tree cut: out 15 September 2015Adam Dick ~ Western Mensurationists Meeting25

15 September 2015Adam Dick ~ Western Mensurationists Meeting26

 49 plots  Sampled trees with a mBAF1 prism  1400 trees sampled ▪ Measured tree DBH ▪ Distance and azimuth to each tree ▪ Took photographs at each plot 15 September 2015Adam Dick ~ Western Mensurationists Meeting27

15 September 2015Adam Dick ~ Western Mensurationists Meeting28  Sampled across range of densities  Stand types  2 camera models  Olympus D550Z, 3 megapixels  Canon PowerShot SD200, 3.2 megapixels

Spatial tree mapping  Azimuth calculations  Linear regression  Field measurements vs. measurements from photo 15 September 2015Adam Dick ~ Western Mensurationists Meeting29

Spatial tree mapping 15 September 2015Adam Dick ~ Western Mensurationists Meeting30  Distance calculations  Linear regression  Field measurements vs. measurements from photo

Spatial tree mapping  Photography is underestimating the distance  Azimuth is generally good  Relative positions of the trees is good  Need to adjust the focal length 15 September 2015Adam Dick ~ Western Mensurationists Meeting31

Angle count sampling (ACS) TREE VISIBILITY BY BAF SELECTION TREE VISIBILITY BY DISTANCE 15 September 2015Adam Dick ~ Western Mensurationists Meeting32

Angle count sampling (ACS) 15 September 2015Adam Dick ~ Western Mensurationists Meeting33

 BAF calculations  Field measurements vs. measurements from photo 15 September 2015Adam Dick ~ Western Mensurationists Meeting34

 Other Applications  As a monitoring tool  Repeated measures 15 September 2015Adam Dick ~ Western Mensurationists Meeting35 Plot 52 – Pre Harvest Plot 52 – Post Harvest  Maintain data integrity  Prescription training tool