Chromosome Numbers of Cultivated Junipers

Abstract

Of 31 cultivars and five varieties in six species of Juniperus, 20 are diploids (2n = 22); three, triploids; 13, tetraploids. Juniperus communis, J. horizontalis, and J. sabina are diploid; and J. squamata is tetraploid. Cultivars of J. chinensis are diploid, triploid, and tetraploid, and of J. virginiana, diploid and triploid. The triploids, J. chinensis `Blue Cloud' and `Hetzii' and J. virginiana `Grey Owl,' appear to be hybrids between the tetraploid J. chinensis `Pfitzeriana' and diploid J. virginiana `Glauca.'