City Forestry staff performs weekly, if not daily observations of the Grandfather Tree.  One thing we look for is how the Grandfather Tree is doing compared to other “undisturbed” bur oak trees.  Fortunately, the oak woodland where the Grandfather Tree was moved from serves as an excellent “control area” for our comparisons.  Observations are recorded relating to leaf formation and drop, leaf size and color, twig growth, and other tree reactions from a variety of environmental factors including diseases and insect damage.  In summary, our observations from this past growing season include:

1.                   The Grandfather Tree began 2002 bud break (new leaves began to unfold) on May 15, about a week behind other bur oaks.  Budbreak for 2003 occurred on April 23.  This date is considerably earlier than what occurred in 2002, and again the tree was about a week or so behind other “natural” bur oaks in the same area.  Leaf development for 2003 was slower than normal, so full leaf out took place in late May, the same as most other years. 

2.                  The Grandfather Tree’s leaf size and color was consistent to what is normal for this tree species.  Leaf samples have been collected and analyzed since 1999 for comparison purposes.  Leaf color is observed as it indicates overall tree health and any deficiencies that may be occurring internally to the tree.

3.                  During summer 2002, the Grandfather Tree had a minor case of jumping oak gall, an insect caused reaction that slightly deforms the leaf surface.  This condition (see more details and photos in the July 2002 update) is not life threatening and was controlled through a  2003 insecticide application that took place on April 23.

4.                  Also on April 23, 2003, the Grandfather Tree was treated by Rainbow TreeCare with a growth inhibitor, Cambistat This material helps trees adjust to changes in their environment (i.e. transplanting) by reducing canopy growth and redirecting this energy to other, more critical, parts of the tree’s system such as roots, defense mechanisms, and energy storage.  Benefits of this application may not be seen immediately, but should result in an enhanced root system, a higher tolerance to insects and disease, and improved drought and heat resistance.

5.                  The Grandfather Tree has received adequate natural moisture during most of 2002 as the summer and fall months were very wet.  The excessive rainfall did not adversely affect this tree as it sits in an area that is relatively high compared to surrounding land; therefore drainage off this site was good.  Actually, this high amount of rainfall was just what this recovering tree needed, as artificial watering by staff did not have to occur more than a half a dozen times.  Likewise, the spring of 2003 has received adequate rainfall.  When installed soil moisture tensiometers indicate a drying of subsoil, the tree is watered by city forestry staff. 

Physical changes that have occurred in the vicinity of the Grandfather Tree include final site grading and landscape installation.  The protective fence previously around the tree has been removed, but the large organic mulch area will remain to assist the tree’s recovery.  Upon completion of construction at this site, during summer of 2003, the grounds near the Grandfather Tree will be comprised of a short grass prairie area with scattered small trees and shrubs.   

Visitors to the City of Eagan web site are encouraged to stop by and check on the Grandfather Tree’s condition.  Please keep in mind however, that this large tree has gone through a dramatic change during the transplant process.  Even though all necessary steps have been taken by city forestry staff, as well as by consulting arborists, to ensure the survival of this huge bur oak tree, it will take several years before the tree is expected to fully recover.  The good news is that to date, all conditions indicate that this big oak tree is on its’ way to getting settled into its’ new home. 

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