1. Agency Report: University of NW/College of Natural Resources/Department of Forest Resources.

   A. The research project that utilized both aerial photography and ground-truthing data to track the health of the bur oaks subjected to construction damage in 1997 at Minnehaha Falls Park will be concluded this summer. Following the final aerial photography flight and data analysis, a summary report will be included in the Shade Tree Advocate.

   B. A new research study on stem-girdling roots (SGRS) will begin this spring, in cooperation with the TRE nursery at the University of MN. In this study, we will investigate two items: 1. How quickly do SGRs begin stem tissue compression, and 2. Does grafting of the root to the stem ever occur, or is it strictly a matter of the stem including the conflicting root.

   C. The Nicollet Island, brownfield tree performance study has had its first monitoring/data collection visit. The trees experienced a fairly low mortality rate for the first winter, and oddly enough, no critter damage to any notable degree. These trees will be monitored two times a year, and monitoring reports will be given to MPRB and Tree Trust.

   D. The Forest Resources Extension web site (http://www.cnr.umn.edu/FR/extension) has two, very appropriate and graphic sites for this time of the year: Tree Planting 101, and How to Prevent Storm Damage. Visit them.

   E. The MNSTAC web site http://www.mnstac.org has had 1584 hits in the last 10 days. Also, every Shade Tree Advocate issue is now available to view and/or print, on this web site.

2. Research and Education Committee.

   A. At our last meeting, we reviewed the draft of the planting specifications being developed by the Department of Natural Resources. It is the opinion of the group (by unanimous vote) that MNSTAC Research and Education Committee should promote the development of Minnesota guidelines/specifications for tree selection and planting, based in part on the review of this draft, the MNDOT specifications, and new research in planting/long-term health.

   B. The spring issue of the Advocate should be mailed out in early June.

3. Field reports.

   The big issue this spring has been the winter damage to evergreens around the state. Extensive browning of conifers has become more obvious, almost on a daily basis. From my observations and reports to me, the primary causes were:

   A. Extended period of snow cover, especially late into the winter, combined with exposure to southern sun. The heat from the sun (direct) and reflection off the snow resulted in extensive desiccation of the foliage. As temperatures warmed, the dying needles have become more obvious.

   B. Exposure to winter winds, and subsequent desiccation.

   C. Record amounts of deicing salts used not only on highways and streets, but also sidewalks and parking lots. The spray salt drift has caused extensive needle and bud death on those conifers close to major roads. Also, I can't remember the last time that the death of turf adjacent to sidewalks -and parking lots has been as extensive and chronic as it has been this spring.

   The big issue is to prevent people from running out and cutting back all of those "dead" evergreens. I have been monitoring the conifers on the campuses of the University and in the field nursery, and the vast majority of the damage has been restricted to the foliage. Buds and candles and needles are already expanding, and will cover the denuded areas after the dead foliage falls.

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