Are Tree Species Diversity and Water Quality Related?

Summary

How important is tree species diversity? Does species diversity affect water quality? How is it related to stormwater management? This presentation will show how the 1970’s outbreak of Dutch Elm Disease (DED) correlates to declining water quality in Minneapolis’ Chain of Lakes. After canopy cover decreased dramatically, over 15 square miles in 20 years, in Minneapolis following the 1970’s DED outbreak, water quality also significantly declined. It took tens of millions of dollars to turn the water quality clock back to 1970, pre-DED. If Minneapolis’ 1970’s urban forest had been more diverse, canopy cover would not have changed as dramatically due to DED. How will Minneapolis’ urban forest be affected by Emerald Ash Borer? How can we protect the Chain of Lakes, Minneapolis’ crown jewel, from future impacts of massive loss of tree canopy? This presentation will present strategies to increase urban forest species diversity to minimize canopy cover loss from major pest and disease outbreaks, thereby also minimizing the effects of canopy cover loss on surface water quality.