1931 Iris Verna

Addisonia page 15, plate 520, 1931

IRIS VERNA
Violet-iris

Native of the Coastal Plain and adjacent Piedmont of the southeastern United States

Family Iridaceae, Iris Family

Iris verna L. Sp. PI. 38. 1753.

Compared with the eastern North American tall irises, the dwarf ones are now kno^\^l to be in a striking minority. When Linnaeus published his "Species Plantarum" in 1753, only two North American species of iris were known. One of these, the common blue-flag, which he named Iris versicolor, has already been figured in Addisonia (Plate 316), and the other is here described. Both had been collected by John Clayton on the Coastal Plain of Virginia, and catalogued in Gronovius' Flora Virginica in 1737.

Although no fossil irises are knoTvn, so that it is not possible to trace the genus far back into the geologic past, the more recent history of some of the species can be inferred from their present day distribution. Prior to the Tertiary epoch, the Coastal Plain as we now know it was non-existent, and plant species which now occur upon it must represent descendants from those which at that time grew in other provinces, especially in the southern Alleghenies and in the Piedmont plateau. As the newly deposited strata gradually emerged from the sea, seeds of many of the upland plants became dispersed over the fresh laud surface, and in cases where the soil and climatic conditions proved favorable, new colonies were developed. In some cases the descendants which proved adapted to the strange surroundings are morphologically indistinguishable from those which remained behind. In others, the diiferences in physiological influences which made survival in the new territory possible were accompanied by differences in morphology as well.

The violet iris group appears to represent an instance of the latter type of relationship.

On comparing the plants of violet iris which at present grow in the Piedmont of North Carolina and adjoining states with those found on the Coastal Plain, it is found that the latter have developed a more lax habit, with slender, long jointed rootstocks, and a smaller, usually more fragrant flower which has narrower-clawed sepals and longer-clawed petals. These features persist throughout its known range, which extends from central Georgia to southeastern Pennsylvania, on the Coastal Plain and rarely just above the Fall Line on the Piedmont.

Iris verna occurs native in sandy or peaty soil which is strongly acid in reaction, and attempts to cultivate it in ordinary non-acid

For more information on historic Irises visit the Historic Iris Preservation Society at

-- BobPries - 2014-12-09