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2.04.10 Vegetation Information <br />COLLECTION AND ANALYSIS OF SHRUB AND TREE DATA <br />Shrub heights and densities and tree heights, densities, and diameters at breast <br />height (DBH) were measured at each cover transect location. In some vegetation types <br />additional sample sites were randomly located to meet sample requirements. <br />The crown height of the first two individuals of each shrub species with a canopy <br />overlapping the transect line were measured to the nearest centimeter. Likewise the <br />height and DBH of the first two individuals of each tree species with canopies <br />overlapping the transect line were measured. DBH's were recorded to the nearest <br />meter. Accuracy of tree height estimates was improved through the occasional use of <br />an Abney inclinometer, tape measure, and geometry calculations. When the appropriate <br />number of tree shrub species was not present along the transect for measurement, <br />those individual tree and shrub species nearest the transect line were selected and <br />measured. <br />Quadrats were used to collect density data. A rectangular quadrat 50 meters by 5 <br />meters was established along the cover transect. The number of mature (greater than <br />1.3 meters in height) trees rooted within the quadrat were recorded by species. A <br />circular quadrat with a 2.5 meter radius (19.6 m2 in area) was centered at the end of the <br />line transect and shrubs counted by species. A square quadrat 5 meters by 5 meters <br />located at the end of the line transect was used in the Juniper Woodland affected and <br />reference areas. Shrub and tree data were analyzed statistically using the same OSM <br />formula for cover, and value with density used for the mean. <br />COLLECTION AND ANALYSIS OF PRODUCTION DATA <br />Circular plots in one meter square in area were used for production estimates. <br />The current year's growth of all herbaceous plants was clipped. All graminoids were cut <br />and sorted by individual species while forbs were combined into a single category. Each <br />production plot yielded on composite sample. <br />In the laboratory, clippings were over -dried at 1050 for 24 hours and weighed to <br />the nearest tenth of a gram. Data were recorded as grams per square meter (g/m2) and <br />converted to pounds per acre Ib/ac) using the multiplier of 8.91. Statistical adequacy <br />requirements for production were calculated using the OSM formula above, except that <br />mean production was used in place of mean cover. <br />PR -02 2.04-54 10/12 <br />