Lumpers Or Splitters
F. C. Galle
Callaway Gardens, Pine Mountain, Ga.
In pursuit of native azaleas, one soon finds many exciting, colorful plants that do not fit the 'norm.' For the 'splitter,' this may be a stumbling block to find new names and to substantiate a 'new species,' with no regard to the existing taxonomic problems. For the 'lumper,' these intra-specific natural hybrids are accepted, without attempt to name the unlimited color forms.
In Georgia, one can find several species of native azaleas and concurrently natural hybrids growing in the same area. The color slides will show the variations found in an area which is predominately Rhododendron speciosum Oconee Azalea, and where R. canescens and R. viscosum are also nearby. While these three species usually do not flower at the same time, synchronous flowering had been observed three years in ten. In one area of northwestern Georgia, I have also observed a fourth species, R. alabamense, also in flower with the other three species mentioned.
R. speciosum Oconee Azalea, is typically orange to orange-red. In the same area, one will often find, in lesser number, natural hybrids, varying from deep pink to peach and shades of yellows. R. speciosum has eglandular flower tubes and glabrous flower buds. Many of the hybrids will have glandular flower tubes and semi-glabrous buds. Usually pubescense will be observed on the lower bud scales.
To the 'lumper,' this offers a challenge to duplicate, by hybridizing, these colorful plants found in nature. With slides, I wish to show a few of the resulting hybrids. Our first crosses were made in 1954 and 1958, with additional crosses made each year.
1. 61 x 2, R. speciosum x R. canescens moderate pink flowers, fragrant, winter floral buds pubescent.
2. 54 x 4, R. alabamense x R. calendulaceum. All seedlings are yellow and fragrant. The best is vivid yellow, white throat and pink tube. Several sister seedlings are light yellow, with the same white throat, pink tube and with pinkish stamens. One is all yellow. All flower intermediate between the parents.
3. 54 x 1, R. prunifolium x R. arborescens and 54 x 3 R. arborescens x R. prunifolium. There were no advantages noted in the reciprocal cross. Flower color varies from light yellowish pink to deep pink. All plants varying in color from the two parents were noted to have some degree of fragrance. Of the 175 seedlings, ten had the appearance of R. prunifolium, being orange-red, with no fragrance. Some of the color variations were observed to have attractive candy striped flower buds. Plants flower in early to mid July.
4. 60 x 36, R. prunifolium x R. serrulatum. All seedlings have varying shades of orange yellow flowers, slight fragrance, and some with distinct pink tubes. All flower in later April-early May, before either of the two parents.
At Callaway Gardens, we have been unable to grow for any length of time named cultivars of the Mollis, Ghent, Exbury, and Knap Hill azaleas. The exceptions noted are 'Pallas', 'Daviesi', and 'Hugo Koster'. This same observation has been made in other areas of the Lower South. However, some of my friends in Atlanta and North Georgia are reporting varying success.
5. 58 x 11 'Hugo Koster' x R. speciosum. Four seedlings now eight years old with flowers intermediate in size, being 1½ to 1¾ inches across, varying in color from yellowish orange to orange-red. All have slight musty fragrance.
6. 54 x 5 'Narcissiflora' (Ghent) x R. alabamense. All seedlings are vigorous, fragrant and vary from a 'dirty' pink to pure white. One has large white flowers 1½ inches across with a strong yellow spot.
Before this distinguished group, I hesitate to report this last seedling as a true hybrid. 61 x 1 'Treasure' x R. alabamense. Have only one weak seedling to survive. The deciduous plant flowered for the first time this spring, with fragrant pink flowers. The flower bud is not typical of a native azalea.
We have only F1 plants flowering to date, with many other intraspecific seedlings, crosses and F2 hybrids, coming on.
We are layering some of these selected plants for further observation. The final slide shows a method of propagating native azaleas by root cuttings.
For the 'lumper,' hybridizing deciduous azaleas for the South has exciting possibilities.