ARCHIVED REPORTS_YEAR SIX (2013) PHYTOREMEDIATION TREE MONITORING REPORT

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SECTION 4:TREE MONITORING RESULTS This could be caused by high boron,salinity or plant pathogens;however,the cause is g uncertain. Year 5 (2011) Area AA had a tree survivorship rate of 100 percent in Year 5 (2011) (Appendix A).This is the same as Year 4 (2010).The survivorship rate in Years 1 (2007),2 (2008) and 3 (2009) was also high(96 percent in all three monitoring years). Area AA is one of two planting sub areas onsite with 100 percent survivorship for more than one consecutive year. The average health and vigor score recorded in 2011 was 2.3 (Appendix A),slightly lower than the value calculated in 2009 and 2010 (2.4 in both years) (Table 4-2).This score is roughly in between a"medium' and"high" rank.In Year 5 (2011) the Fremont cottonwood in this planting sub area had a slightly lower health and vigor score (2.2) compared to black willow (2.3) (Appendix A). The lower health and vigor score for the cottonwood in this planting area is mainly due to"leaf scorch" (leaf margins that appeared"burned"). This could be caused by high boron, salinity or plant pathogens;however,the cause is uncertain. Year 6 (2012) , Area AA had a tree survivorship rate of 100 percent in Year 6 (2012) (Appendix A). This is the same rate as Year 4 (2010) and Year 5 (2011).The survivorship rate in Years 1 (2007), 2 (2008) and 3 (2009) was also high(96 percent in these three monitoring years). Area AA is the only planting sub area onsite with 100 percent survivorship for more than three consecutive years (Table 4-2). The average health and vigor score recorded in Year 6 (2012)was 2.5 (Appendix A). A score ' of 2.5 is in between a "medium' and"high" rank.This rank is slightly higher than scores calculated in all previous monitoring years (scores ranged between 2.2 and 2.4) (Table 4-2). Leaf scorch (leaf margins that appeared"burned")was noted on cottonwood and willow in this planting sub area in Year 6 (2012). Fremont cottonwood and black willow both had the same vigor score of 2.5 (Appendix A). The leaf scorch could be caused by high boron, salinity or plant pathogens;however,the cause is uncertain. 4.4 Area B Area B is composed of lower and middle planting zones (Figures 1-3 and 1-4).A total of 49 trees were installed in this area. Three tree species (box elder,Fremont cottonwood, and black willow) were planted according to these zones. 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 4-8