SPECIAL SAMPLE-PLOT GUIDE TAPES 351 



Other Plots. — Strip plots, known as transects and bisects, 

 are sometimes used to advantage in revegetation studies. A 

 transect is merely a narrow, much-elongated sample plot; 

 whereas, a bisect, also much elongated, aims to show the ver- 

 tical relation or cross-section, as it were, of associated plants, 

 the underground parts as well as the aerial growth often being 

 shown (Fig. 127). The width of the bisect, like that of the 

 transect, is never great, varying from a mere line to a few inches. 

 The advantage in the use of transects and bisects lies in the 

 fact that they may run from one plant community or society 

 into another, or from one exposure or gradient into quite a 

 different one. 



The mapping of the transect or bisect is done much the same 

 as that of a chart plot. Special tapes of varying length, con- 

 veniently segregated, are used. Because of the great length of 

 the average " belt " transect, that is, one whose width is more 

 than that of a mere line, it is most convenient to map the vege- 

 tation in strips or segments on the same sheet. These strips 

 appear on the chart at regular intervals, the first one being placed 

 to the extreme left on the sheet and running from top to bottom, 

 the second to the right of the first, the third to the right of the 

 second, and so on. 



Special Sample-Plot Guide Tapes. — Accurately constructed 

 and otherwise satisfactory plot guide tapes are not obtainable on 

 the market. Accordingly special metal tapes have been devised.^ 

 Although the sketch (Fig. 128) is designed on the basis of a 

 meter unit, any length desired may be made up according to 

 the following description. Inches and feet may be substi- 

 tuted for the metric scale. 



Each set consists of four boundary tapes, as shown by " A," 

 and two di\dsion tapes, as shown by " B." The boundary tapes 

 are 13 millimeters wide, and their total length is 1.113 meters. 

 A satisfactory thickness of material is approximately .025 of an 

 inch, as that weight affords the convenience of rolling up the 

 tapes for transportation. To insure ample strength for much 



* Sampson, Arthur W., "The Quadrat Method as Applied to Investigations in 

 Forestry." Forest Club Annual, Univ. of Nebr., Vol. 6, pp. 7-10, 1915. 



