2009-03-12_REPORT - M1983194 - Laserfiche WebLink

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within twenty 9.6 square foot quadrates at the peak of production for most native plant species. Quadrates were protected by enclosures to prevent vegetation removal by grazers and browsers. The enclosures are relocated each growing season to prevent multiple years of protection. Above ground vegetative biomass production was measured using a double sampling procedure of estimates adjusted by actual values from representative samples. Six of the twenty quadrates were estimated then clipped to obtain an actual weight correction factor to adjust estimated weights. Clipped samples were oven dried to obtain an air dry weight correction factor for green weights. Ground cover values were made from visual observations of cover type within each quadrate and reported as a percentage of total ground cover. A summary of the data collected 2008 in comparison with data collected from previous years is presented in the tables that follow. Ground cover data is presented in Table 1, biomass production in Table 2 and species composition in Table 3. The data presented in these tables is summarized from the quantitative data collected in 2008 and presented in the Appendices. The scientific and common names of the all the plant species encountered in the study are presented in the tables in the Appendices. The ground cover data in Table 1 is summarized by class of vegetation and cover type from data presented in Appendix Table Al. The ground cover data in Table Al are shown by plant species or cover type. The production data presented in Table 2 is summarized from the annual above- ground vegetation biomass production for each plant species as shown in Appendix Table Al. The species composition data presented in Table 3 is summarized by class of vegetation from the percent composition of each plant species encountered as determined by each species contribution to total biomass production as shown in Appendix Table Al. Table 1- Ground Cover for Native Rangeland (control) Jul 2008 2004 2005 2006 2007 2008 %Cover %Cover %Cover %Cover - - %Cover Native Grasses 27.2 26.6 27.7 6.9 2 27.70 Native Forbs 10.1 12.6 6.1 5.6 6.65 Annual Grasses 0.2 1.2 0.9 1.2 1.40 Weed Forbs 1.1 3.0 0.8 0.6 0.75 Native shrubs 13.9 14.8 149 18.7 19.80 Moss/Lichens 4.5 3.6 5.8 9.1 9.40 Vegetative Litter 7.6 7.4 14.3 12.6 13.15 Bare Ground 34.0 30.3 29.1 24.5 21.15 Rock 1.4 0.5 0.4 0.80 0.00 Total 100.0 100.0 100.0 100.0 100.00 The ground cover values have held relatively consistent over the 5 year period shown. Ground cover of native grasses has remained nearly constant. A 16% increase in cover of native forbs occurred in 2008, but still remains below cover values measured in 2004 and 2005. Native shrubs continue to show increasing cover; 5% in 2008 and 30% over the 5 year period. 2008 Annual Report 15 of 28