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9/7/2010 Forester's Report Prepared for: Senior Housing Partners Prepared by: Stephen Nicholson CF Site Location: 3220 Lake Johanna Blvd., Arden Hills, Minnesota In early August, 2010 a tree inventory update and assessment was performed at wooded and landscaped property on Lake Johanna. A previous tree inventory was prepared by Sunde Land Surveying some years earlier. All field work and identification was performed by International Society of Arboriculture Certified Arborists Using the City of Arden Hills definition of Significant Tree found in Zoning Code Chapter 13, Subd.167, our current inventory finds 329 trees on the property that meet this definition. Since the original survey site conditions have changed. Our update found: 1. Many trees in the original survey were too small to meet the minimum size limit defined in City Code, 2. Many trees have died since that survey, 3. Some trees have been damaged by storms to the point they are not structurally sound, 4. Some trees are now diseased and declining that were once healthy. We also found some trees misidentified (incorrect species) and added twelve that were not found in the original survey. At least three tree diseases are active on this site and account for many of the dead, dying and declining trees we culled from the earlier survey. One area on the north facing hillside has a soil borne disease, armillaria that is affecting many trees, killing some and causing dieback in the crowns of others. This naturally occurring disease is part of natural decay process that returns dead and dying trees back into soil. However, when under stress, such as from drought, otherwise healthy trees succumb to this disease. Drought from years past may be the stressor that has lead to the armillaria induced decline and death of so many trees at this site. Young, healthy and vigorous trees are not likely to be at risk from this disease. Also present are Oak wilt and Dutch elm disease. Only a couple of oaks appear affected which indicates it may be new to the area. Dutch elm disease has likely been on site and in the neighborhood for years and will continue to kill elms here and throughout Arden Hills. Most of the wooded areas of this site are heavily invaded with European buckthorn. Some invasive honeysuckle can also be found. More than 50 ash trees were identified but none appear to have Emerald Ash Borer (EAB) at this time nor is it confirmed to be present in the City of Arden Hills. However, this area is close to the original EAB find in Saint Paul, so it will be important to monitor for this pest as long as these trees remain on site. Inspection of an historic 1957 aerial photo of this area indicates that the east and north facing wooded hillsides were largely open at that time and that the current woods are relatively young 1