Broader Understanding of Biodiversity and Genetic Diversity In Landscape Plantings Is Needed

Many researchers and practitioners have been aware of the importance of landscape plant biodiversity and genetic diversity for decades.  The Irish potato famine and Dutch elm disease are classic examples of problems resulting from lack of diversity.  Recent pest outbreaks, such as emerald ash borer and Asian longhorned beetle, have renewed concerns over these issues, yet little headway has been made in increasing diversity in landscape plantings.  New research indicates that urban trees are becoming more uniform genetically due to cloning of a few preferred cultivars; thus, they are losing potential resiliency to pest and environmental stresses at a time when these threats are increasing due to climate change.  To address this, it is important to know the level of understanding of these issues in the green industry.  A survey distributed to Washington wholesale nurseries on plant species diversity issues showed that most respondents were aware of the issue, but lacked an in-depth understanding of it.  More education is needed on why plant species diversity among landscape plants is important.