Olson Memorial Highway
The Olson Memorial Highway (OMH) elm evaluation study is a cooperative study between the Minneapolis Park and Recreation Board and the University of Minnesota, Department of Forest Resources. The study was designed to test lesser known Dutch elm disease (DED) resistant elm varieties. At the time of planting, there was little performance information on different DED resistant elm varieties for the Twin Cities.
In 2003, 10 varieties of Ulmus spp. thought to be resistant to Ophiostoma ulmi and Ophiostoma novo-ulmi (Dutch Elm Disease) were planted in North Minneapolis for assessment. The study area spans the median of Olson Memorial Highway from the Van White Memorial Boulevard to Thomas Avenue North. Annual developmental pruning was performed for three years before data was collected. The varieties that were included in the study were Accolade, Cathedral, Danada Charm, Discovery, New Horizon, Pioneer, Princeton, Triumph, and Vanguard. In 2007, 2008, 2010, 2011, and 2012, condition ratings and caliper data were collected. The condition rating system assigns a numeric value 0 - 4 with 0 being dead, and 4 being no obvious defects for both stem and canopy.
The study is being concluded in 2017. Due to expansion of the Metro blue line, the trees in the study area will need to be removed. Over the summer, trees were assessed again for growth, survival, and condition. Recommendations for transplant will be made for trees with a DBH under 10 inches and a condition rating no lower than 2.75 for the crown and stem.
Click here to view our interactive story map.