ARCHIVED REPORTS 2009 YEAR 3 PHYTOEMEDIATION TREE MONITORING REPORT

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' SECTION 4:YEAR 3 TREE MONITORING RESULTS ' Year 1 (2007) Five Fremont cottonwood trees, out of a total of 49 trees (or 10 percent), died in this planting area during Year 1 (2007). The average percent survivorship in this planting area was 90 percent.The average heath and vigor score in 2007 was 1.8,which is slightly lower than a "medium' rank. Year 2 (2008) ' Seven out of 49 trees (or 14 percent) died in this planting sub area.Six of these trees were Fremont cottonwoods,and one was a black willow. The average percent survivorship in this planting area is 86 percent. The average heath and vigor score is 1.6,slightly lower than the ' score of 1.8 calculated in Year 2 (2007).A score of 1.6 is roughly half-way between "medium' and "low' ranks (Table 4-1). ' Year 3 (2009) Tree mortality in this planting area decreased about 10 percent in monitoring Year 3 (2009) compared to Year 2 (2008) (Table 4-1).Two Fremont cottonwood trees (out of 49 trees) died in this planting area in Year 3 (2009) (Appendix A). The average percent survivorship in this planting area in Year 3 (2009) is 96 percent. The average percent survivorship calculated in Year 2 (2008) was 86 percent. The percent survivorship in Year 1 (2007) was 90 percent, about six percent lower than Year 3 (2009). The average heath and vigor score in Year 3 (2009) increased from scores of 1.8 and 1.6 in Years 1 and 2,respectively, to 2.3 (Table 4-2). A health and vigor score of 2.3 corresponds to a slightly higher than a"medium' rank. 4.5 Area C ' Planting Area C is the location of the former groundwater treatment system, and it is underlain by engineered fill (Figures 1-3 and 1-4). Within the compacted horizons,soil texture and fertility are very poor. Fifteen Fremont cottonwood and black willow trees were planted in this area. Year 1 (2007) ' Three Fremont cottonwood trees (or 20 percent) died in this planting area during Year 1 (2007). The average health and vigor score in 2007 was 1.6,which fell in between the"low' and"medium' ranks.This was the second lowest health and vigor score of all the planting areas during Year 1 (2007) monitoring. Year 2 (2008) Survivorship in Year 2 (2008) (80 percent)was the same as Year 1 (2007).This planting area contained the same three Fremont cottonwoods that died during 2007.These trees were replanted in late November,2008, subsequent to the Year 2 (2008) annual tree monitoring. ' Survivorship of these replanted trees will be assessed in Year 3 (2009). SAC11667491PANAGON(YEAR3_2009_HOLTTREE MONITORING_REPORT.DOC) 4.5