Rhododendron 'Tang', which is a 1952 David Leach hybrid documented as Rhododendron cumberlandense 'Scarlet Salute' x 'Red King' 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.
Rhododendron 'Red King' is documented to be a mollis hybrid.
Summary of Ploidy Levels
Diploid Rhododendron cumberlandense,
Diploid Rhododendron molle,
Diploid 'Tang'
Source: Barlett Arboretum
John and Sally Perkins
