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Task B. Production Sampling (cont.) <br /> <br />vary per vegetation type. A square quadrat 1 m2 in area will be used in I ~~- <br />the meadow vegetation type while quadrats 1 m x 3 m may be employed in the ~ <br />xeric pinyon vegetation type. Within each quadrat the current year's <br />growth of herbaceous plants will be clipped. Craminoids will be sorted <br />by species and forbs will be combined except for those forbs which have <br />a significant cover. Cacti, cushion plants, trees, and shrubs will not <br />be clipped. The clipped material will be oven dried (105°C for 24 hours) <br />in our laboratory and weighed to the nearest tenth of a gram. Production <br />will be expressed in grams per square meter and pounds per acre. <br />Task 9. 1Joody Density Sampling <br />A quadrat system would be used for sampling woody plant density. <br />We will use a rectangular shaped quadrat 1 m by 50 m in areas for shrubs <br />and 5 m by 50 m for tree species. We will record the number of individual <br />woody plants rooted within the quadrat by species. We will express density <br />for each species and for the total of all species per vegetation type <br />and reference area as the number per quadrat, the number per acre, and <br />the number per hectare. We will either achieve sample adequacy or take <br />50 samples (quadrats) in both affected and reference areas. <br />Task 10. Sample Adequacy <br />Sample adequacy for cover, production, and density will be <br />calculated separately for the affected and reference areas in each <br />vegetation type. He will test sample adequacy for cover, woody plant <br />density, and production per the following formula: <br />2 2 <br />t s <br />nmin = d2x2 <br />where nmin = minimum sample size <br />t = t value for 2-tailed test at 90X confidence for herbaceous <br />vegetation types (t=1.645) or 80~ confidence for woody <br />vegetation types (t=1.282) <br />s = sample standard deviation (n-1) <br />d = detectable change in the mean (lOL, d = 0.1) <br />8 = sample mean <br />All parameters will be tested at the 90 percent confidence level <br />with 10 percent change in the mean (d = 0.1) for herbaceous vegetation <br />types and with 80 percent confidence for woody vegetation types. <br />-3- <br />