JARS v48n2 - Subsection Taliensia

Subsection Taliensia
Represented by R. bureavii
Warren Berg
Port Ludlow, Washington

The following article by Warren Berg on the subsection Taliensia was written for publication in an upcoming book on the 45 sections of rhododendron species, with full color illustrations by Marianna Kneller. Miss Kneller is a RHS gold medalist and has received many awards for her exceptional botanical illustrations. This very promising book will be published by David & Charles, G.B., with distribution in America.

The Taliensia subsection is a large, complex group of plants, with uncertain relationships. With the addition of the former Lacteum series and 13 new species, it is even more obscured, making a total of more than 60 species. Horticulturally speaking, these species include some of the most beautiful in the genus. Many have outstanding foliage, with variations of indumentum and tomentum to enhance their charm, as well as many other fine qualities, including hardiness, form, and often compactness. They are usually long-lived and are quite free flowering when mature. In the past, this subsection was rather looked down upon, especially by Kingdon Ward, because they were so slow to bloom and rather difficult to root. However, with improved propagation methods and a greater tolerance for the time it takes to flower, their popularity in the garden has mushroomed considerably.
Of the 13 new Taliensia that Peter Cox mentions in The Larger Rhododendron Species , I have been fortunate enough to find several in my explorations. These include bhutanense which was found in Bhutan on the top of the Rudong La at 13,600 feet. This is a very fine new species, and is probably the most westerly representative of this subsection. While in the upper Wolong Panda Reserve in Szechwan in 1983,1 found balangense. It is a very handsome plant with white flowers and white indumentum, growing at nearly 10,000 feet. As Peter mentions in his book, the classification may be a little suspect, but the Chinese consider it to be a Taliensia. Another new one which happens to be particularly attractive is coeloneuron . We found it on two different expeditions on the east side of the Erlang Shan in southeast Szechwan at about 9,300 feet. It is closely related to wiltonii , but with more bullate leaves and a much thicker indumentum. It may be the most easterly Taliensia and possibly the least hardy, because of the elevation at which it grows. However, it is certainly well worth having.
It's very difficult to pick the finest member of this very interesting subsection, but for me it probably comes down to bureavii or proteoides . Since my years of searching for the latter in Yunnan, Szechwan, and Tibet have been to no avail, I have chosen the former as the best overall representative. I have found it both in Yunnan and Szechwan. I believe there would be very little disagreement that a properly grown, mature bureavii , in its best form, such as the Exbury A.M., is about as handsome as any species in the genus. It normally is easy to grow, when given partial shade. The dark, shiny, bullate foliage, with the rich, rusty red indumentum is absolutely outstanding, even for the most discriminating. When mature, it is free flowering with flushed rose or white suffused rose blooms, fading to white and most often with crimson spots, which enhance its beauty. There are usually 10 to 15 flowers in the truss.
Rhododendron bureavii is found both in Yunnan and Szechwan at altitudes from as low as 9,000 feet, up to over 14,500 feet. The Chinese consider the ones in Szechwan to be bureavioides , but these have been merged into bureavii . The difference is not significant. In 1983, I found a large population of bureavioides in northwest Szechwan near Mt. Sigunion. These were growing only along the rivers and streams at about 12,000 feet, with many fine forms having a heavy indumentum. Some of the bushes were as high as 25 feet. This trip was made in the fall, so I am unable to report on the flower. On another expedition in 1989, just north of Kanding in western Szechwan, we found another fine population. It was in a forest preserve called Chi-Sa-Hi. Again the bureavii were growing mostly along the river and lake shore. Because this was a reserve, many of the plants were very large. One in particular, the best form I have seen in the wild, was at least 20 feet in diameter and about 25 feet high. It was very heavily indumentumed, with a layer of tomentum on the upper surface of the leaves.
It is only in recent years that bureavii has been used much in hybridization. Halfdan Lem was one of the first in the United States to use it in his crosses. This was with 'Fabia' of which he named one 'Hansel'* and the other 'Gretsel'*. These hybrids, and many since by other hybridizers, all have beautiful foliage and habit, inherited from the bureavii . I used it with yakushimanum in 1965. Others have also made this cross, all with good results. But I must admit, some are slow to bloom.
As perhaps you have surmised from the above, R. bureavii is probably my favorite species and is therefore well represented in my garden.

Editor's Note: * Name unregistered, but not in conflict with a registered name.