Circular 333. U.S. Dept. of Agriculture 



PLATE 3 



Instruments used in Sample-Plot Work. 



A, Surveying and height-measuring instruments: 1, Standard United States Forest Service compass; 

 2. Klaussner hypsometer; 3, Abney level; 4, steel tape and reel (a buckskin loop on the head end of the 

 tape is easier to manage under forest conditions than the handle commonly used by surveyors); 5, 

 standard United States Forest Service hypsometer. B, Other common instruments: 1, Increment- 

 core measuring device (a core is shown in the slot beneath the magnifying glass). 2, 3, 4, Diameter tapes: 

 2 has a steel pin to hold the end in place, 3 a loop, and 4 a hook. 5, Tags made by embossing numbers 

 on aluminum tape, nail hole at right end. 6, Increment borer with dagger extractor. 7, Swedish bark 

 punch. 8, Timber scribe. 9, Bark blazer or scratcher. 10, Wooden calipers, United States Forest 

 Service type. 



