Where we are headed Map reading and compass use Species identification (FOR 219) Tree measurement (diameters and heights) Defect recognition and determination Quality determination (grading) Use of timber cruising tools Traverses Elementary use of aerial photography Compass and GPS Loggers tape Dendrometer and Hypsometer Increment Borer Flagging and Stakes Maps, Aerial Photos, Cruising plan Axe and paint Data recording device (electronic or manual) Prism Calculator Boots Chaps First aid kit Hard Hat Safety glasses Vest Radio Water supply Part 1 - Diameter An instrument used to measure trees Diameter Breast Height Average diameter at 4.5 feet (1.4 meters) Easiest to measure, less taper, not height of cut Outside bark Uphill side of tree Circumference: = Radius: = /2 Area: = 2 Basal Area(ft2)= .005454 DBH2 basal area of a forest stand can be found by adding the basal areas of all of the trees in an area and dividing by the area of land in which the trees were measured. Basal area is generally expressed as ft2/acre Held 25” from eye One-inch diameter class examples 5-inch class = 4.6 to 5.5 inches 9-inch class = 8.6 to 9.5 inches Two-inch diameter class examples 12-inch class = 11.0 to 12.9 inches 14-inch class = 13.0 to 14.9 inches Can average DBH for stand and/or by species After calculating Basal Areas for all trees. You can average the BA for the stand and/or by species The square root of the mean BA/.005454 is the quadratic mean diameter or the diameter of the tree of mean basal area. = /.005454 Needed for tree form, taper, and volume. Can determine merchantable height. Need to be able to do this easily, quickly and safely. Review To use the one-half diameter method, make two marks opposite each other on the stem at 4.5 feet. Measure the distance between the marks with the diameter tape and double the measurement to determine DBH. Repeat the process for the other tree. If these measurements are at equal distance from 4.5 feet, average A and C to arrive at DBH measurement. If point A and point C are at unequal distances from 4.5 feet, interpolate the distances to arrive at DBH measurement a. Measure diameter above DBH where shape is normal, point A in diagram at right. b. Measure height to the point where DBH was taken. c. Determine average taper from comparable trees of the same species in immediate area. d. Interpolate DBH measurement "C" based on diameter measurement "A", the estimated average taper, and length "B". For split trees, measure DBH with calipers or use the one-half diameter technique. Make two marks opposite each other on the stem at 4.5 feet. Measure the distance between the two marks with a diameter tape and double the measurement to determine the diameter Since DBH includes bark you must estimate what the measurement would be including the missing bark. If all bark is missing, try to get a measure from similar nearby trees. -- Diameter tape (D-Tape). Adjust the tape at a normally rounded position to allow for the catface portion missing. If the tape is not adjusted but is pulled tight, the tape will be straight across the missing portion and the diameter read will be less than it should be. -- Calipers. Measure DBH at right angle to catface. -- One-half Diameter Technique. Use this technique on trees growing together. Crown Width Highly correlated to tree vigor and other measurable parameters. Helps predict response from silviculture treatments like thinning or fertilization Useful in ecological studies 1. Average of Maximum and Minimum diameters 2. Average of Maximum diameter and the one perpendicular to that axis 3. Average of some random width and the perpendicular axis width 4. For highly irregular crowns more than 2 measurements may be averaged How, What, Where, Why Easily seen from a distance Type of mark may be distinctive for type of tree (i.e. diagonal line for boundary, horizontal line for pulp tree, etc. Boundary trees marks visible from three sides. Boundary trees visible from each other. Survives after operation Downhill side Remove loose bark, etc first Paint into bark furrows and between root swellings Include tree and soil Law enforcement ramifications Black paint used first to hide old paint All forest service paint contains tracers - Thus USFS paint requires tight supervision, inventory, security. May be used when need to identify this tree is temporary or short lived. Cruise ID number painted on tree Cruiser initials also Paint applied towards plot center if part of sample point.