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4-37 <br />breast height (DBH) of the first two individuals of each tree <br />• species with canopies overlapping the transect line were mea- <br />sured. Tree DBH's were recorded to the nearest centimeter and <br />heights were estimated to the nearest meter. Accuracy of tree <br />height estimates was improved through the occasional use of <br />an Abney inclinometer, tape measure, and geometry calculations. <br />When the appropriate number of tree or shrub species was not <br />present along the transect for measurement, those individual <br />tree and shrub species nearest the transect line were selected <br />and measured. <br />Quadrats were used to collect density data. For trees, a <br />rectangular quadrat 25 meters by 5 meters was established <br />along the cover transect and the number of mature (greater <br />than 1.3 meters in height) individuals rooted within the quadrat <br />was recorded by species. Likewise, a rectangular quadrat 1 <br />meter by 25 meters was located along the cover transect and <br />the number of shrubs rooted within the quadrat recorded by <br />• species. This method was used in the Shadscale Cheatgrass and <br />Shadscale Wildrye vegetation types. A circular quadrat 2.5 <br />meters radius (19.6 m2) centered at the end of the cover tran- <br />sect was employed to determine shrub density for the Greasewood <br />vegetation as sampled in 1980. Finally, a rectangular quadrat <br />25 meters by 5 meters was used for shrub density in the Juniper <br />Woodland. <br />Tree densities are expressed as the number of individuals per <br />125 m2, per hectare (ha), and per acre (ac). Similarly, shrub <br />densities are recorded as the number of individuals per 125 m2, <br />19.6 m2, hectare (ha), and acre (ac). <br />4.5.1.4 Sample Adequacy <br />Sample adequacy for cover, production, and density was calculated <br />using the formula below. <br />• = 2s2t2 <br />nmin (dx)2 <br />