Landsford Canal State Park lilies

Exclusive and gorgeous plant

During the ice ages, the rivers of the southeast of the United States served as refugia for diverse species of plants and animals and today have very high biological diversity. Many of these plants and animals are unique to this area. Unfortunately, much of this was lost during the 19th and 20th centuries due to logging, dams, agriculture, and pollution.

Hymenocallis genus

We know more than 60 species of spider lilies. All of them grow in the central part of the Americas from the United States to Peru. Many species of these flowers grow in marshes and banks of rivers. All spider lilies have large, white, and fragrant flowers. Flowers of some species have a green or yellowish tint. Most of these 60-plus species are very rare and some, unfortunately, are extinct by now.

Shoals spider lily (Hymenocallis coronaria) was discovered in 1783 in Savannah River (Georgia) by William Bartram. It is one of the most impressive endemic plants of the southeast states of the United States.

Habitat

This plant grows only in shoals – shallow sections of fast-flowing streams. Streams should be clean and shoals – sunlit. Of course, there are not too many places with such a set of specific conditions. Thus the shoals spider lily is rare by its nature. Humans have not been helpful in this, to say it mildly. They inundated the fast-flowing rivers with dams and agricultural run-off silted the formerly clean rivers.

As a result in 1997, specialists knew only 65 populations, most of them quite small, with less than 10 plants. But in some locations, thousands upon thousands of these beautiful flowers grow. The three largest populations are in the Cahaba River National Wildlife Refuge (Alabama), Flint River (Georgia) and Landsford Canal State Park (South Carolina).

Flowers in the water

Shoals spider lily has quite large seeds: 3 by 4 cm and larger. These seeds fall in the stream and are brought by its force to some crevice between the stones, where it stops and can start growing.

In April flower stalks appear above the water and flowers open in late May-early June. Lily rises up to 1 m above the water but flower stalks are up to 1.25 m tall. The flower stalk has some 3-12 buds. Each flower lasts only for one day. It opens in the late evening – and this is the best time to admire these fragrant, absolutely unique “meadows”.

Research shows that these plants are pollinated by diverse insects. Much of this work could be done by Plebeian Sphinx Moth (Paratrea plebeja)) and other moths during the night but many insects (and also hummingbirds) come also during the day. Flowers are beloved by the gorgeous pipevine swallowtail (Battus philenor) and tiger swallowtail (Papilio glaucus).

Landsford State Park

Catawba River near Lancaster has rapids (remember – shoals serve as a habitat of spider lilies!) which prevented the navigation in the river. Thus in 1820-1835, there was built a canal system to bypass these rapids. Of course, as it was usual in these times, much slave labor was involved.

Soon after came another transport technology – the railroad. The use of the canal was not feasible anymore and it was abandoned. Now we can admire the remaining structures – but nature has taken over.

Now there is a state park. For the most part of the year, people just walk in the forest and look at the ruins of canal structures and often take a boat trip in the fast stream of the Catawba River. But every year in May-June comes the great flowering… If you have a chance to be there, don’t miss it!

References

1. Scott H. Markwith, Michael J. Scanlon. Multiscale analysis of Hymenocallis coronaria (Amaryllidaceae) genetic diversity, genetic structure, and gene movement under the influence of unidirectional stream flow. American Journal of Botany 94(2): 151–160. 2007. Visited on 23rd November 2019.
2. Scott H. Markwith, Kathleen C. Parker. Conservation of Hymenocallis coronaria genetic diversityin the presence of disturbance and a disjunct distribution. Conserv Genet (2007), 8:949–963DOI 10.1007/s10592-006-9249-z. Visited on 23rd November 2019.