Article of the Month - September 2007 - Identification and Control of Coral Ardisia (Ardisia crenata)

Figure 1. Coral ardisia in a hardwood hammock.
Photograph by Michael Meisenburg Coral ardisia (Figure 1), also known as coral berry, spice berry, and scratchthroat was introduced into Florida in the early 1900's for ornamental purposes. It has since escaped cultivation and is found in hardwood hammocks, and other moist woods of natural areas and grazing lands. Documented herbarium specimens have been collected from 19 western and south-central Florida counties (Wunderlin and Hansen 2004). It is considered invasive by the Florida Exotic Pest Plant Council (www.fleppc.org) and the IFAS Assessment (http://plants.ifas.ufl.edu/assessment/pdfs/concl_genus.pdf) (Fox et al. 2005).

Figure 2. Coral ardisia leaves are waxy with a bright, shiny appearance.
The leaves may contain substances that are toxic to cattle and other livestock. Photograph
by Brent Sellers. Identification. Coral ardisia is an evergreen sub-shrub reaching heights of 1.5 to 6 feet. It tends to grow in multi-stemmed clumps. Leaves (Figure 2) are alternate, 8 inches long, dark green above, waxy, without hairs, scalloped margins and calluses in the margin notches. Flowers (Figure 3) are typically pink to white in stalked axillary clusters, usually drooping below the foliage. The fruit (Figure 4) is a bright red, globose, 1-seeded berry, measuring approximately 0.25 inches in diameter. White-berried populations also exist.

Figure 3. Coral ardisia has pink to white flowers in
axillary stalks that tend to hang underneath the foliage. Photograph by Michael Meisenburg. Toxicity. There is no published literature supporting that coral ardisia is toxic. However, there are two cases in Florida where this plant was suspected to be the causal agent for the death of livestock in 2001 and 2007. Berries tend to persist on the plant nearly year-round. It is suspected that the berries and/or foliage are poisonous to livestock, pets, and humans.

Control. Control of coral ardisia can be accomplished by two methods. Low-volume foliar applications of 5% v/v of Garlon 4 or Remedy provides suppression of this plant, but complete foliar coverage is essential. Basal bark applications with an 18% v/v solution of Garlon 4 or Remedy in an oil carrier can also be utilized for suppressing this invasive weed. Do not apply more than 8 quarts of Remedy or Garlon 4 per acre and treat no more than 10% of the total grazed area if applying greater than 2 quarts per acre. Use care when applying high rates of these herbicides when temperatures exceed 90oF as these formulations can volatilize under such conditions. Regardless of application method, retreatment will be necessary for complete control. For more information on basal bark applications, see EDIS publication entitled 'Herbicide application techniques for woody plant control' (http://edis.ifas.ufl.edu/AG245).

Figure 4. Bright red berries of coral ardisia. It is thought
that consumption of the berries has resulted in death of livestock in 2001 and 2007 in Florida.
Photograph by Michael Meisenburg.
Literature Cited:

Fox, A. M., D. R. Gordon, J. A. Dusky, L. Tyson, and R. K. Stocker. 2005. IFAS Assessment of the Status of Non-native Plants in Florida's Natural Areas. Cited from the Internet (June 8, 2007), http://plants.ifas.ufl.edu/assessment/.

Wunderlin, R. P., and B. F. Hansen. 2004. Atlas of Florida Vascular Plants (http://www.plantatlas.usf.edu/). [S. M. Landry and K. N. Campbell (application development), Florida Center for Community Design and Research.] Institute for Systematic Botany, University of South Florida, Tampa.