Armatage Alder Amendment Study
A major goal of the partnership between the University of Minnesota and the Minneapolis Park & Recreation board is to research new varieties of trees that can survive and thrive in harsh city boulevards. One such tree is Prairie Horizon® Manchurian alder. While relatively new to the Twin Cities area, Prairie Horizon cut its teeth on the tough, dry plains in North Dakota at NDSU's woody plant breeding program led by Dr. Dale Hermann. Previous success with Prairie Horizon in Armatage encouraged expanding its use from one small planting to a neighborhood-level research trial. Small-statured and fast-growing make this a great new potential tree for Minneapolis. Additionally, Armatage is known for its high concentration of green ash, making preparation for ash removals even more critical. With results from this research we hope to find more trees that will fill open planting sites and create soil conditions that will enhance their long-term survival and establishment.
In the growing season prior to installing the project, all trees were established into two different root types. Half were held in both a gravel bed containing 3/8in washed river rock and the other half were containerized into #15 RootTrapper® fabric containers. In the fall of 2012, trees were planted in typical Minneapolis boulevard conditions with different combinations of an organic matter product. This product is produced by a Minnesota company and is made from composted wood waste adjusted to a carbon to nitrogen ratio (C:N) of 20:1. Trees received one of the following treatments, replicated six times for each root type: organic matter topdress (3ft x 2in), organic matter incorporation (added to backfill 1:1 with existing soil), organic matter topdress + incorporation, or no treatment (planted using existing soil only).