Rhododendron 'Pink Ember', which is a Earl Sommerville hybrid documented as (Rhododendron cumberlandense x Rhododendron viscosum) x Rhododendron arborescens, has been determined to be a diploid using flow cytometry by
Dr. João Loureiro, Dr. Silvia Castro, José Cerca Oliveira, and Mariana Castro
Plant Ecology and Evolution Group,
Centre for Functional Ecology,
Department of Life Sciences,
Faculty of Science and Technology,
University of Coimbra, Portugal.
Summary of Ploidy Levels
Diploid Rhododendron arborescens,
Diploid Rhododendron cumberlandense,
Diploid Rhododendron viscosum,
Diploid Rhododendron 'Pink Ember'
Source: Planview Nursery
John and Sally Perkins
