Vireya Rhododendrons At Lyon Arboretum
University of Hawaii
The Harold L. Lyon Arboretum is an organized research unit of the University of Hawaii at Manoa dedicated to research, education and public service as related to its unique resources. The 124 acre site is located in Manoa Valley on the island of Oahu, four and a half miles inland from Waikiki. Typically the environment is one of a tropical rainforest, averaging approximately 165 inches of rainfall per year. Elevation ranges from 425 feet along its lower boundary to about 2,000 feet along the ridge tops of the Ko'olau Mountains, its upper boundary.
Photo by Robert Hirano
Its resources include approximately 8,500 plant taxa with about 4,000 species. Major collections are: Palms, 506 taxa; Heliconia, 106 taxa; Araceae, 354 taxa; Marantaceae, 199 taxa; Zingiberaceae, 113 taxa; Ficus, 99 taxa; Cordyline, 311 cultivars; native Hawaiian plants and Hawaiian Ethno-botanical Collection.
The first Vireya species and hybrids from the Royal Botanic Gardens, Kew, England, Rhododendron javanicum ssp. brookeanum var. gracile, cultivars, 'Pink Seeding', 'Red Prince', and 'Sir George Holford', were introduced to Lyon Arboretum from Longwood Gardens in 1967. Within a few years these plants began flowering: 'Pink Seedling' and 'Sir George Holford' flowered for the first time in July and August 1971 respectively; 'Red Prince' first flowered in 1973; and R. javanicum ssp. brookeanum var. gracile, received as R. brookeanum var. gracile, P.I. 257475 flowered for the first time in December of 1976. In 1972, a few more species were introduced to the Arboretum, including R. aurigeranum, R. cf. dielsianum, R. macgregoriae, and R. zoelleri. These plants were received as rooted cuttings and all flowered within two years. In a five year period, R. aurigeranum has been recorded in flower every month of the year; while R. macgregoriae has been observed in flower in every month with the exception of May and August. R. herzogii has flowered in every month except February, July and December. Since data collected was from a very small sample of plants, it appears that these species are capable of flowering in any given month here at the Arboretum. These plants have thrived and formed the nucleus of our Vireya Rhododendron Collection.
The early emphasis was placed in breeding and selecting ornamental types for Hawaii's climate. Many crosses and selfs were made and tested including many of Mr. Peter Schick's hybrid seeds and seedlings. We currently have over 35 hybrid taxa with over several hundred seedlings in various stages of evaluation. Many of these have flowered or are now coming into flowering. These hybrids are greatly contributing to the beauty of the islands with their bright colors.
|R. aurigeranum x R. herzogii
Photo by Robert Hirano
|(R. zoelleri x R. lochiae) x R. zoelleri
Photo by George Ring
Today, emphasis is on the development of a Vireya species collection in order that we may preserve the existing germ plasm of this extremely valuable group of plants for research and posterity. In November 1987, I was fortunate in collecting a Vireya species from the mountains near Banaue, Ifugao, Luzon, Philippines. The plant is now growing in our greenhouse and we are eagerly awaiting its first flowers. Only through plant collecting, exchanges, gifts, and purchases, will we attain our goal of establishing as complete a living outdoor collection of Vireya rhododendron at Lyon Arboretum. We now have a total of 29 species in the collection (see attached list). With help from the American Rhododendron Society and its members, this dream will become a reality and we will reach our goal of the 300 plus species listed by John Womersley in, A Census of the Species of Rhododendron, sect. Vireya. Many of the species growing today are clones, coming to the Arboretum as a vegetative cutting. It is our wish that someday, seedling populations of all the Vireya species will prosper on the grounds at Lyon Arboretum.
Vireya Rhododendron Species At Lyon Arboretum
26 February 1988
Accne# Species 72.203 R. aurigeranum 75.274 R. aurigeranum 82.701 R. aurigeranum 81.197 R. buxifolium var. robustum 82.699 R. christianae 72.207 R. cf. dielsianum 88.069 R. dielsianum 88.063 R. goodenoughii 73.232 R. herzogii 75.406 R. inconspicuum 75.407 R. inconspicuum 82.689 R. jasminiflorum 88.066 R. javanicum 67.142 R. javanicum ssp. brookeanum var. gracile 88.067 R. kawakamii 75.404 R. konori 82.631 R. konori 88.079 R. laetum 82.698 R. leptanthum 82.710 R. leptanthum 77.1038 R. leucogigas 88.070 R. lochiae 88.071 R. longiflorum 88.072 R. loranthiflorum 72.204 R. macgregoriae 88.073 R. pauciflorum 82.705 R. phaeochitum 88.074 R. retivenium 88.076 R. rhodoleucum 82.692 R. robinsonii 81.198 R. rugosum var. corifolium 82.700 R. scabridibracteum 88.077 R. solitarium 82.704 R. superbum 88.078 R. wrightianum var. wrightianum 72.205 R. zoelleri 72.206 R. zoelleri
Mr. Hirano has a long standing interest in growing Vireya rhododendrons in Hawaii. The ARS Research Foundation recently awarded an additional grant to the Lyon Arboretum for continuation of their work with Vireyas.