A Report From The A.R.S. Species Committee
Milton Walker, M.D., Creswell, Oregon
In the late afternoon of a wet day, a grower of many years' experience was beard to remark-"I didn't expect to get anything out of today's trip except pneumonia, but I've learned something, and it was fun too."
Such remarks are not unusual among Species Committee members who often have gone out on inspection trips with one foot dragging, only to find that visiting gardens in search of unusual or better forms of the species Rhododendron is both instructive and fun indeed. There seems to be still a great many unanswered species questions, at least for some of us. Here are a couple.
R. haematodes (Fig. 31) is usually considered to have a rather obovate or oblong leaf with the apex quite rounded. However, we have found in many gardens, a form called by the owners, 'Exbury haematodes' that differs in leaf shape. It is actually more elliptic than obovate with an acute apex, some leaves being almost lanceolate in their narrow tapering.
Fig. 31. R. haematodes
We find on checking The Species of Rhododendron, 2nd. ed., that the leaf is described as oblong and obovate, with the apex obtuse to rounded. No statement is found of variations in the leaf shape that might be construed to fit the elliptic shape and acute apex of the so-called 'Exbury' form.
The question therefore arises should we who are growing this 'Exbury' form consider it a hybrid, or is it possible that it is a form of R. haematodes with a leaf shape differing from that described as typical? It seems almost sacrilegious to question such an authoritative book as The Species of Rhododendron, yet when published some thirty-two years ago, the editor himself said in his introduction to this monumental work, "It is therefore with no idea of finality that the present books appears."
The efforts of the Species Committees, in the four selected areas, have been limited these first few months, to just locating the ten species under study. No attempt has been made as yet to evaluate the plants recorded. While it is hoped to uncover 'better' forms of the species and eventually make them available to everybody, at the present time we are concerned with just being able to recognize plants that are representative of the species. This in itself presents problems.
In the garden of Halfdan Lem of Seattle is a plant that in most respects fits the description of the species R. cardiobasis and yet we had thought that R. cardiobasis was no longer in cultivation. This beautiful mature plant, standing eight feet tall, and as much across, looks like a huge R. orbiculare. In fact it was so labeled in the garden of James Barto of Junction City, from whom Mr. Lem secured the plant. Mr. Barto must have prized this plant because "it was in his private garden close to the steps leading into his home," according to Mr. Lem. So many unusual species have come from Mr. Barto's collection, that it is quite within the realm of possibility that we have stumbled onto a species that was thought not to have been in cultivation.
As we search for descriptions of this plant, we find that it is not described in The Species of Rhododendrons, 2nd. ed., but that the Rhododendron Handbook 1956 describes it as follows, "A shrub up to ten feet, resembling R. orbiculare, with round stiff leathery leaves, heart-shaped at the base. The flowers with 7 lobed corollas are large, white or rose colored, 6-7 in a loose truss." Mr. Lem's plant fits the above description perfectly, except that every truss has 15-18 flowers, not 6-7.
This question of a species having more flowers in a truss than the described plant was discussed with Ben Nelson in Seattle, and a trip was made by the writer to the Nelson garden in Suquamish. There, Mr. Nelson pointed out a plant labeled R. argyrophyllum. We counted 23 flowers in every truss on this plant, which certainly had all the other outward appearance of R. argyrophyllum, but which the Species book says should have only 6-12 flowers in a truss. These are examples of some of the interesting problems that have presented themselves to the members of the Species Committees. Even the recognition of plants truly representative of their species is not always a simple matter. It may be that there are certain variations from the described characteristics of a species that we will have to recognize by describing different forms of the typical species. But just how much variation from the published botanical description will be permissible? These and other questions that have arisen are making the species study stimulating and exciting.