ARCHIVED REPORTS 2009 YEAR 3 PHYTOEMEDIATION TREE MONITORING REPORT

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SECTION 4:YEAR 3 TREE MONITORING RESULTS ' The average health and vigor score for 2008 was 1.3, slightly lower than the average calculated for 2007 (1.6). Health and vigor scores of both species contributed to the decline. This health and vigor score was the lowest of all six sub areas. , Year 3 (2009) The rate of survivorship in Planting Area C in Year 3 (2009) increased to 93 percent from ' 80 percent as recorded in both monitoring Years 1 and 2 (Table 4-1). One Fremont cottonwood died in Year 3 (2009) (Appendix A)compared to three trees in Years 1 and 2 (2007 and 2008). ' The heath and vigor scores for trees within this planting area in Years 1, 2,and 3 are below a rank of 2 (or in between"low" and "medium' health and vigor ranks) (Table 4-2). The ' health and vigor scores calculated in Year 3 (2009) increased slightly compared to the scores in Year 1 (1.6) and Year 2(1.3).The Year 3 (2009) score of 1.9 is only slightly between a "medium" rank (Table 4-2). The trees within this planting area are short for their age and it , is likely that the roots are still confined to the engineered fill zone. Tree growth and health and vigor scores are expected to increase once tree roots extend beyond this compacted layer. , 4.6 Area D ' The south end of Planting Area D abuts Whiskey Slough Road, and the site gently slopes down to the slough levee at the north end (Figures 1-3 and 1-4). This planting area is composed of two distinct planting zones (the middle and the higher planting zones) , (Figure 1-3). Fifty trees,composed of four species in roughly equal proportions (box elder, Fremont cottonwood,valley oak, and black willow),were installed in this area. ' Year 1 (2007) Eleven trees died in Area D (or 22 percent) during Year 1 (2007). Black willow had the t highest mortality rate at this site,followed by box elder.One Fremont cottonwood and one valley oak also died. The average percent survivorship in this planting area is 78 percent. h1 2007,this was the only planting sub area with a percent survivorship lower than the 80 ' percent threshold. The average heath and vigor score was 1.5, about halfway between"low" and "medium' ranks. This health and vigor score was the lowest of all six sub areas. Year 2 (2008) Limited replanting was conducted in Area D during Year 1 (2007) but mortality in Year 2 still remained high in Area D. Nine trees in this planting sub area (or 18 percent) died in ' Year 2(2008).Similar to 2007,black willow had the highest mortality rate,followed by box elder. One Fremont cottonwood and one valley oak also died. In 2007, survivorship dropped below the 80 percent threshold,but it increased slightly to 82 percent,just above the threshold,in Year 2 (2008). The average heath and vigor score was 1.4,about halfway between"low" and "medium' ranks.This health and vigor score was the second lowest of all six sub areas. 1 46 SAC/1667491PANAGON(YEAR3 2009_HOLTTREE MONITORING_REPORT.DOC)