While the plant pictured below at the Dawes Arboretum refers to the plant a 'chinensis', 'Humphrey Welch and Gordon Haddow' in 'The World Checklist of Conifers' refer to the plant as X media which is probably correct. They state that the plant is a strong-growing mutation from 'Pfitzeriana Glauca', with flecks of pale yellow with an unrecorded origin.
I would add that, in my opinion, the plant that I saw at the Dawes Arboretum during the Conifer Society tour in 2004 was quite attractive and where zonally appropriate is more worthy of planting and of similar merit (if not better) than the much more common Juniperus sabina Variegata.
