| Author | Parks & Hardin | |
| Distribution | Throughout the Mountains and Piedmont, as well as in the extreme western Coastal Plain, and sparingly in the southern Coastal Plain. Essentially absent from the eastern two-thirds of the Coastal Plain, and absent from the Sandhills proper.
This is the Southern species of the former Erythronium americanum (broad sense) complex. It occurs north to MD, WV, and KY south to western FL and central AL. As there is still confusion between the two, at least determining which of the large number of specimens of "E. americanum" now belong to E. umbilicatum, the BONAP range map is a bit uncertain in some parts of the range.
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| Abundance | Common to locally abundant, especially in the central and northern Piedmont. Generally fairly common to common in the Mountains and the southwestern Piedmont; the lack of SERNEC specimens from several southwestern counties is certainly an oversight, as the BONAP map shows records for essentially all counties there. Fairly common to locally common in the extreme northwestern Coastal Plain, but local in the southern Coastal Plain, where mostly limited to brownwater sites such as the Cape Fear River floodplain. It is nearly always much more common and widespread than the very similar E. americanum in all counties where both occur, except perhaps along the upper Roanoke River floodplain in Halifax and Northampton counties. | |
| Habitat | This species occurs in a wide variety of moist to somewhat mesic forest sites, usually under hardwoods. It is widespread in bottomland forests, other streamside forests, wooded slopes, and gentle slopes; it can be a dominant species in Mesic Mixed Hardwood Forests. One subspecies -- E. umbilicatum ssp. monostolum -- grows in "High elevation coves, slopes, and grassy balds, moist forests" (Weakley 2018). Even though the Mountains contain large amounts of very rich forested slopes, it is this species and not the "rich soil" E. americanum that is the common species in that province. | |
| Phenology | Blooms mostly from February into April, and rarely even in January. It blooms around 1-2 weeks earlier at a given site than does E. americanum, where both occur together. | |
| Identification | The leaves of both species of trout-lilies are easily identified by anyone who spends much time in the woods in spring. Each plant has two basal leaves, each about 5 inches long and 1 inch wide, quite thick, fleshy, and pale green, with a mottling of purple-brown. Both species grow in very extensive colonies, and thus you must have the flowers and capsules to make the identification, though Weakley (2018) indicates that the stolons can be used for separation. When in bloom, each species has a single flower atop a roughly 6 inches tall naked flowering stalk. This species has the 6 yellow tepals about 1-1.2 inches long, with each tepal strongly recurved. If you check the inner 3 tepals, this species tapers to the base without an auricle; E. americanum inner tepals have an auricle ("ear") at the base. E. umbilicatum has slightly smaller flowers, with tepals about 1 inch long, and they are a medium yellow. E. americanum flowers are a richer yellow, to an almost golden-yellow, and the tepals can be about 1.2 inches long. (However, flower size and color can be tricky to use for identification.) As most folks are familiar, when E. umbilicatum is finished blooming, the flower stalk flops to the ground, seemingly not strong enough to keep the capsule off the ground. After blooming, E. americanum has a graceful, "swan-like" appearance, as the flower stalk remains erect, with a slight nod at the top such that the capsule is held horizontally or somewhat ascending. Also, the end of the capsule is indented or "dimpled" in E. umbilicatum, as opposed to rounded or pointed in E. americanum. For most biologists, 95% or more of your encounters with a trout-lily colony will be E. umbilicatum, but you must always be careful before you claim a colony as the relatively scarce E. americanum. As a reminder, this latter species always requires high pH soil, which should eliminate most forested habitats in the Piedmont and upper Coastal Plain. What frustrates many a biologist is the fact he or she may see hundreds or thousands of leaves, but with nary a single flowering stalk. For every plant that flowers, most seemingly do not in a given year. However, given the right time and place, a colony of hundreds or thousands of trout-lilies in full bloom is quite a spectacle. | |
| Taxonomic Comments | Several decades ago, this species was pulled out of the former E. americanum and described as a new species, as botanists recognized the differences in the capsule shape and shape of the inner tepals. It is split into two subspecies, the widespread nominate form -- E. umbilicatum ssp. umbilicatum, and a high elevation one -- E. umbilicatum ssp. monostolum. The range map on this website for that subspecies is almost certainly incomplete.
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| Other Common Name(s) | Dimpled Dogtooth Violet (a very poor and misleading name) | |
| State Rank | S5 | |
| Global Rank | G5 | |
| State Status | | |
| US Status | | |
| USACE-agcp | FAC link |
| USACE-emp | FAC link |
