|Division:||Magnoliophyta - Flowering plants|
|Class:||Magnoliopsida – Dicotyledons|
| Cnidoscolus stimulosus|
|Natural range of Cnidoscolus stimulosus from USDA NRCS Plants Database.|
Common names: Finger-rot; Spurge-nettle; Tread-softly; Bull-nettle
Synonyms: C. urens (Linnaeus) Arthur var. stimulosus (Michaux) Govaerts; Bivonea stimulosa (Michaux) Rafinesque
Cnidoscolus stimulosus is a perennial herbaceous species. It tends to grow erect from a tuberous base, and is marked by the presence of urticating hairs.
Cnidoscolus stimulosus is a herbaceous, monoecious, erect or reclining perennial, growing 0.5-10 dm tall with palmately dissected or lobed, alternate leaves. The entire plant is covered with stinging trichomes. The leaf lobes or dissections lobed or prominently dentate, very rarely entire. The inflorescence is terminal, compound, dichasial cyme, often appearing axillary because of the elongation of axillary branches with terminal inflorescence. The central flower in each dischasium is uaully pistillate, the lateral is usually staminate. The calyx is white in color, salverform, the tube grows 1-1.5 cm long, equaling or almost equalling the lobes. The petals are absent. There are 10-30 stamens, united at the base. There are 3 stigmas, each with 3-5 lobes. The capsule is 3-locular, each locule is 1-seeded. The seeds are dark-brown in color, growing 8-9 mm long, and 4-5 mm broad, with a conspicuous caruncle at the base.
Cnidoscolus stimulosus is found in sparsely canopied upland habitats that occur on deep, well drained, sandy substrate suitable for construction of Gopher tortoise burrows. It also occurs in dry sandy flatwoods, sandy barrens, mixed hardwood hammocks, sand dunes, longleaf pine-wiregrass-scrub oak sand ridges, and mesic longleaf pine savannas. Cnidoscolus stimulosus is a feature of sandhill communities with frequent occurrence in the understorey. Finally, it occurs in some disturbed areas, such as roadsides, old fields, bulldozed clearings, railways, and residential lawns.
It has three seeds fruit and produce seeds with elaiosomes.
This species has been observed to flower within three months following burning.
“In all of these species, seeds are forcefully expelled after the fruit matures and dries. Three of the ballistic euphorbs (C. stimulosus, C. argyranthemus and S. sylvatica) produce seeds with elaiosomes and all of the ballistic species are collected by ants, in particular Pogonomyrex badius Latreille (Long and Lakela 1971; N.E. Stamp and J. R. Lucas, personal observation).”  This species is thought to be dispersed by ants and/or explosive dehiscence. 
It is included in the flowering plant survery – post burn – in Heuberger’s study. Cnidoscolus stimulosus was one of the plant species to increase in abundance recovery post-fire in Rosemary scrub ecosystem. Cnidoscolus stimulosus also resprouted post-burn after fire was reinstated into the ecosystem.
It resprouts and flowers within two months of burning in the growing season.KMR In southeastern Polk County, C. stimulosus was observed blooming 54 days after a prescribed burn on December 22, 2016. Similarly, in Charlotte County, FL, it was observed blooming about 19 days post burn. Overall, the species appears to be tolerant of fire, and potentially benefits from it, but it does not seem to be dependent on the presence of fire on the landscape.
Use by animals
“Seeds were found in middens of harvester-ant nests of Pogonomyremex badius Latreille. In addition, seeds of all three plant species were observed being carried into the ant nests and then later deposited uneaten at the nest perimeter.” Gopher tortoises (juveniles and adults) feed on Cnidoscolus stimulosus. Included in gopher tortoises’ scat.
Conservation and management
Cultivation and restoration
References and notes
- Florida State University Robert K. Godfrey Herbarium database. URL: http://herbarium.bio.fsu.edu. Last accessed: June 2014. Collectors: H. E. Ahles, L. C. Anderson, W. R. Anderson, L. Baltzell, D. Burch, K. C. Burks, R. J. Campana, J. Carmichael, A. F. Clewell, D. Demaree, F. S. Earle, P. Elliot, D. L. Fichtner, T. Floyd, E. Freeman, W. B. Fox, H. Gale, M. A. Garland, H. E. Grelen, W. T. Gillis, R. K. Godfrey, J. Haesloop, B. K. Holst, C. Hudson, P. Jones, W. Kittredge, G. R. Knight, R. Komarek, R. Kral, D. W. Mather, S. McDaniel, R. S. Mitchell, S. J. Noyes, K. Oakes, G. W. Ramsey, G. W. Reinert, A. B. Seymour, D. B. Ward, J. H. Wiese, and R. L. Wilbur. States and Counties: Alabama: Geneva. Florida: Alachua, Bay, Broward, Calhoun, Citrus, Dade, Franklin, Gadsden, Hernando, Jackson, Jefferson, Lake, Leon, Liberty, Madison, Marion, Monroe, Nassau, Okaloosa, Orange, Pasco, Pinellas, Sarasota, Suwannee, and Wakulla. Georgia: Bullock, Grady, and Thomas. Mississippi: near Ocean Springs, George, and Forrest. North Carolina: Carteret, Cleveland, Cumberland, Duplin, Harnett, Hertford, and Pender.
- Radford, Albert E., Harry E. Ahles, and C. Ritchie Bell. Manual of the Vascular Flora of the Carolinas. 1964, 1968. The University of North Carolina Press. 661-2. Print.
- Glitzenstein, J. S., D. R. Streng, et al. (2003). [Abstract] Long-term seasonal burning at the St. Marks National Wildlife Refuge, north Florida: changes in the sandhill plots after 23 years. Second International Wildland Fire Ecology and Fire Management Congress and Fifth Symposium on Fire and Forest Meteorology, Orlando, FL, American Meteorological Society.
- Observation by Edwin Bridges in southeastern Polk County, FL, February 14, 2017, posted to Florida Flora and Ecosystematics Facebook Group February 15, 2017.
- Stamp, N. E. and J. R. Lucas (1990). "Spatial patterns and dispersal distances of explosively dispersing plants in Florida sandhill vegetation." Journal of Ecology 78: 589-600.
- Nelson, G. PanFlora: Plant data for the eastern United States with emphasis on the Southeastern Coastal Plains, Florida, and the Florida Panhandle. www.gilnelson.com/PanFlora/ Accessed: 7 DEC 2016
- Kevin Robertson personal observation at Pebble Hill Plantation, Georgia and Tall Timbers Research Station, Florida, July 2015.
- Kirkman, L. Katherine. Unpublished database of seed dispersal mode of plants found in Coastal Plain longleaf pine-grasslands of the Jones Ecological Research Center, Georgia.
- Heuberger, K. A. and F. E. Putz (2003). "Fire in the suburbs: ecological impacts of prescribed fire in small remnants of longleaf pine (Pinus palustris) sandhill." Restoration Ecology 11: 72-81.
- Menges, E. S. and N. M. Kohfeldt (1995). "Life History Strategies of Florida Scrub Plants in Relation to Fire." Bulletin of the Torrey Botanical Club 122(4): 282-297.
- Reinhart, K. O. and E. S. Menges (2004). "Effects of re-introducing fire to a central Florida sandhill community." Applied Vegetation Science 7: 141-150.
- Observation by Jake Antonio Heaton in Charlotte County, FL, May 22, 2016, posted to Florida Flora and Ecosystematics Facebook Group May 23, 2016.
- Birkhead, R. D., C. Guyer, et al. (2005). "Patterns of folivory and seed ingestion by gopher tortoises (Gopherus polyphemus) in a southeastern pine savanna." American Midland Naturalist 154: 143-151