Curtis's Botanical Magazine Vol. 42, Nº3423 (1835)
RHODODENDRON ARBOREUM (hybridum), ALTA-CLERENSE.
High-clere hybrid var. of the TREE RHODODENDRON.
Class and Order.
( Nat. Ord.-ERICEAE)
Cal. 5-partitus. Cor. infundibuliformis, 5-loba. Stam. 5-10, declinata: antheris apice biporosis. Capsula 5-locularis, 5-valvis, ab apice dehiscens, valvaum marginibus inflexis dissepimenta formantibus: Receptaculum centrale, 5-angulare. Semina membrana involuta.
(For Specific Character and Synonyms of the Species, see tab. 3290.)
RHODODENDRON alta-clerense. Lindl. Bot. Reg. t. 1414.
For this truly splendid ornament of our gardens, it seems we are indebted to Lord CAERNARVON, who suggested the idea, as stated in the Bot. Register, that "if a hybrid variety could be obtained between RHODODENDRON arboreum and some one of the hardy American species, the result would be a more robust constitution on the one hand, and a greater brilliancy of colour on the other; and also, that if the pollen of R. arboreum could be employed, the stature of the hybrid would also be increased." Such has been the consequence of numerous experiments that have since been tried by various persons who have fertilized the pistil of RHODODENDRON Ponticum, or some of the equally hardy American species with the pollen of R. arboreum, and our shrubberies and open borders can now boast of these favourite and highly ornamental shrubs, equally hardy with the R. ponticum, equally splendid in regard to the size and colour of the flowers with R. arboreum, and blossoming earlier by nearly six weeks than our common hardy sorts. The specimen here figured was in perfection in the Glasgow Botanic Garden the latter end of April, notwithstanding that the season was more unpropitious than usual. The underside of the leaves presents more of the rusty hue of the East Indian parent than the ALTA-CLERENSE of the Bot.Register.