It seems like sesbania is popping up everywhere you turn.
Sesbania punicea or “rattlebox,” has been widely used as an ornamental plant for its attractive compound leaves and bright red colored flowers. Unfortunately, this invasive species has found its way into natural areas as there are dense patches of sesbania in both coastal and upland areas of Gulf County. Sesbania punicea is native to South America. It is a woody shrub that can grow up to 15 feet in height. The fruit and flowers of “rattlebox” are characteristic of those in the legume family. Flowers are half to one long, are orange-red in color, and hang in clusters. Seed pods are three to four inches long and dark brown with longitudinal wings. There are three to nine seeds per pod and make a rattling sound when shaken.
Sesbania is prolific, as it easily spreads by seed. Many seeds are produced per plant, which are readily dispersed by wind and water. Seed pods may also persist on the plant through the winter. Sesbania is able to produce thousands of seeds and fully mature in one year. Germination rate for seed is very high and seed are able to remain dormant for several years in the soil.
Sesbania has several forms. Species herbacea or “coffeeweed”, is a native weed of the U.S. It is a much shorter species with yellow blooms. Sesbania grandiflora or “scarlett wisteria” is a native of Asia. This species falls into the tree category, and has white, red or pink flowers. Both herbacea and punicea species have levels of toxicity, and grazing livestock can be affected.
Sesbania displaces native vegetation and wildlife by forming dense thickets. The greatest environmental impacts are in water bodies or in lower elevations, especially wetland areas. This can cause an aquatic weed concern, as sesbania can decrease water flow and quality, and reduce recreation for boaters, fishers, and other activities in creeks.
How do you control sesbania?
Chemical options are available, but the first step should be cultural or preventative control of sesbania by limiting seed germination through physical removal of existing plants within the landscape and pasture. Removal should occur before seeds are produced. Care must be exercised to prevent seed spread and dispersal during the removal process.
Contact Gulf County Extension Office at 639-3200 for more information.
Supporting information for this article provided by the UF/IFAS Center for Aquatic and Invasive Plants: https://plants.ifas.ufl.edu/plant-directory/sesbania-punicea/ and the USDA website: https://plants.usda.gov/plantguide/pdf/pg_sehe8.pdf
UF/IFAS Extension is an Equal Opportunity Institution.