'Bear Facts' on Gregory Bald
F. C. Galle, Callaway Gardens, Pine Mountain, Ga.
The azaleas of Gregory Bald are a bewildering, bizarre collection. Thousands of plants can be found in every imaginable color, ranging from pure white to pale yellow, salmon yellow, clear pink, and orange-red to red. Many of the flowers are yellow blotched. Many plants are upright, while others are stoloniferous. Foliage varies from normal to deep green, often glaucous beneath, presenting a problem for the taxonomist.
My interest in this complex problem dates back to 1947, while a young staff member of the Horticulture Department at the University of Tennessee in search for a challenging dissertation problem. I realized the potential of this azalea problem after a visit to Gregory Bald with Dr. Aaron ('Jack') Sharpe, former head of the U. T. Botany Department.
Horticulturally these plants are very beautiful, as best described in a letter written by the late Dr. Wendell Camp, "Azaleas, characteristically, are able to pick up and absorb genes from other azaleas and thereby increase their genetic diversity and so on around and around the genetic circle. But aren't they lovely things when they get mixed up and assume the pastel shades or go into the more flamboyant color combinations?"
The eastern treeless mountain balds including Gregory (4,948 ft.), are complex ecological systems. Most of the important ecological factors have been used to explain how a bald comes into existence and how it is maintained. These factors include ice, soil acidity, fire, moisture, parasites and man (cattle).
The azaleas on Gregory are obviously a complex hybrid swarm, as confirmed by Camp1, Skinner3, and other botanists. Basically, there are probably three species involved in the hybridization: Rhododendron cumberlandense, the red and orange-red flowered species; Rhododendron arborescens, which is white flowered with glossy leaves and glabrous stems, and Rhododendron viscosum, with white to light pink flowers, dwarf and stoloniferous.
Cytological studies were made to reveal the chromosome count of various plants on the Bald. The chromosomes of azaleas are inordinately small. Tannin granules and other inclusions make counting very difficult. Meiotic counts from pollen mother cells were attempted, but the proper stage to take the material was not determined. After two years, working with Dr. Taylor of the University of Tennessee and Dr. Alan Conger of Oak Ridge, counts were made from somatic cells of the young growing tips. The total number of counts made were about twenty and all were diploids, 2n=26.
The following was taken from Dr. Hui-Lin Li's2 article, "Chromosome Studies in the Azaleas of Eastern North America,": "Eight collections were made from Gregory Bald, Blount County, Tennessee, which are quite diverse and which, according to Skinner and Camp (1952), intergrade between Rhododendron arborescens, Rhododendron viscosum, and what appeared to be Rhododendron calendulaceum. These plants are all diploids. n=13 (one collection), 2n=26."
Rhododendron calendulaceum is the only reported tetraploid species 2n=52 and is often described as a derived rather than a basic species. Typical forms of the species Rhododendron calendulaceum are thought to be in areas below Gregory Bald, such as Rich Gap, and in other areas of the Smoky Mountains.
A detailed morphological study of the plants was also underway. A map of the area was made and numerous plants were tagged. Originally, about 35 plants in one small sector were tagged, but, later, plants were tagged around the entire area, totaling over 100. The ultimate plan was to sample every plant on the Bald to have a survey of the total gene complex. Information and date to be collected was, briefly, as follows:
- Each specimen tagged according to area or section.
- Flower color and blotch recorded. Florets counted (not less than five groups).
- Fragrance - present or not.
- Size of plant.
- Habit of growth, stoloniferous or not.
- Flower widths measured, not less than five measurements.
- Color of style and glands.
- Leaf color and underside.
- Small specimens pressed for examination.
The plan was then set up indices as suggested by Anderson in "Introgressive Hybridization."
A larger quantity of notes and observations were accumulated over a seven year span. Most of the records were on the 100 or more plants in the Tellico and Nanthahala National Forests. Total number of visits were not recorded, however, seven trips to Gregory were made in one season (a hike of over nine miles round trip).
Unfortunately, I had not considered making notes in duplicate, but today I recommend it strongly for all graduate students. In 1954, on a two-day trip to the Bald, I lost my pack to a bear, including the back notebook of data, records and the map. The real shock over the loss of this data was not felt immediately. Unfortunately, I could not repeat all this information, but I realized that azaleas were a real part of my life, due to the many hours spent with them, plus the knowledge received from my friends and associates. Thus, with a continued interest, I have made repeated visits to Gregory since 1954 and hope to continue in the future. There are indications, some confirmed by botanists, that the plant communities of the balds are ever changing. Only time will tell us the answer to their future. The control of fire, the rutting of wild boars, the increase in brambles and other plants are all factors in these observed changes.
Thus, in 'bear facts', the complete story of the azaleas on Gregory Bald is yet untold and hopefully offers a challenge and intrinsic beauty to the future.
1Camp, W. H., The Grassy Balds of the Great Smoky Mountains of Tennessee and North Carolina, Ohio Journal Science, 31: 157-164. 1931
2Li, Hui-Lin., Chromosome Studies of the Azaleas of Eastern North America, American Journal of Botany, 44: No. 1, 8-14. 1957
3Skinner, H. T., In Search of Native Azaleas, Morris Arboretum Bulletin, 6:3-10, 15-22. 1955
On Appalachian Trails, N. Y. Botanic Garden Journal, 37: 249-265. 1936.