American Rose Annual pp. 41-43 (1917)
On the 1916 Rose Firing-Line
By W. VAN FLEET
Department of Agriculture, Washington, D. C.
Editor's Note.—Among several thoughtful articles upon rose-breeding printed in the 1916 Rose Annual, Dr. Van Fleet's presentation on "Possibilities in the Production of American Garden Roses" was particularly interesting and important. Several careful breeders of roses have written of their conception of its valuable suggestions, and it was undoubtedly one of the most important record statements on the rose ever presented. The paper which follows brings the reader up to date with Dr. Van Fleet's progress.
It will be remembered that Dr. Van Fleet has produced many of our best hardy climbing roses. One just being introduced, "Alida Lovett," is pictured on Plate V, facing page 40.
THE past season did not prove especially favorable for rose pollination among hardy roses in the open, but a fair proportion of hand-fertilized seeds was secured from most of the species and varieties worked with. In March many pollinations of the Cherokee rose, Rosa laevigata, in its typical form and in its pink-flowered varieties Anemone and Ramona, of R. Banksiae, R. xanthina, R. rugosa, R. multiflora, in newly imported types, and a few other species, with a considerable variety of Tea and Hybrid Tea roses, were made at the United States Plant Introduction Garden, Chico, Cal., with very flattering immediate results; but early drought unfavorably affected the development of the hips and only a small proportion came to maturity.
Some sound seeds of most of the crosses were secured, however, R. Banksiae giving the smallest yield, and a few have already germinated. Only double-flowered varieties of the Banksia rose are available at Chico, and they are rarely fruitful. It is to be hoped that the primitive single forms can be secured for breeding purposes, but they appear exceedingly rare in cultivation.
The typical Cherokee yielded a satisfactory crop, considering the adverse conditions. No fruits matured in the pink varieties, though the pollen of Anemone appeared effectual on other species.
During May and June, though much hampered by rain, very numerous cross-pollinations were made at Glenn Dale, Md., between new hardy Chinese species, including R. setipoda, R. Moyesii, and R. sertata, and promising garden and bedding varieties from the American Rose Society's test-garden at Arlington, Va. The fruits of the Chinese species, with few exceptions, were unfavorably affected by the great humidity of the late summer months, but pollen-crosses of all the new species were secured. More than the usual number of pollinations of the older exotic and native species were made, with very fair success in the outcome. Some very striking hybrids of R. Wichuraiana, R. rugosa, R. Soulieana, and R. pomifera, the results of crosses made in 1913-14, were bloomed, and propagations made from the most promising for future trials.
Among second-generation crosses of R. Soulieana and Hybrid Teas there appeared a dwarf, compact plant bearing a profusion of double, fragrant blooms, white with creamy centers, throughout the entire growing season. This newcomer is of the general character of R. Pissardii (R. moschata var. nastarana), favorably known in European rose-gardens, but appears to be a more profuse bloomer as grown here. The original form of R. Soulieana, imported about 1904, winterkills about Washington, but seedlings are quite hardy. A few hybrids with varieties of R. gallica have handsome double blooms, white or clear pink in color. A plant of the type, maintained in a greenhouse, makes tremendous growth but does not bloom, and the same is to be said of R. Leschenaultii, a native of northern India, which throws canes twenty feet long but produces no blooms. This latter is attractive in foliage and habit, but is too tender for northern localities.
After many years of effort and the sowing of innumerable seeds, there has at last appeared two fairly vigorous seedlings of the prized Harison's Yellow rose. They are from chance or self-fertilized hips, all seeds from controlled pollinations having consistently failed to grow, and strongly resemble their parent. Blooms are awaited with interest, as some influence of R. spinosissima or species other than the yellow-flowered R. lutea may be looked for.
Rosa Hugonis up to this time yields seedlings inferior in vigor and attractiveness to the species, both from chance and carefully controlled pollinations. The seeds, though abundantly produced, are low in germinative powers, scarcely one in a thousand coming up the first season after planting. It is to be hoped that this unusually attractive introduction will in time prove amenable to breeding influences, and give us some of the hardy, constant blooming, yellow varieties we are all waiting for.
Rosa Fargesii, mentioned on page 36 of the 1916 Rose Annual, turns out, on no less authority than Dr. E. H. Wilson, to be a deeply colored variety of the very handsome R. Moyesii, but is well worth preservation for its horticultural value.
Two new double-flowered white varieties of R. rugosa that seed with some freedom have been developed, and much progress has been made with dwarf everblooming seedlings of R. Wichuraiana in the third and fourth generations of dilution from the wild type. It appears as if much can be looked for from this particular line of breeding work.