Kudzu, Old World climbing fern, and tropical soda apple are all widely known as invaders which were introduced into the region from faraway and exotic locations. Each has its own story of how it arrived here and escaped into a welcoming environment.
Once established, these and other alien plant interlopers have aggressively pushed out native species and changed the landscape. Wildlife habitats have been altered and millions, if not billions, of dollars have been spent in an effort to control these destructive intruders.
However, not all plants with aggressive and intrusive characteristics are offshore invaders. Brazil pusley, Richardia brasiliensis, is an excellent example of a homegrown (despite its name) vegetative conquistador with a propensity to overtake less dominant species.
Like its relative Florida pusley, this plant is low growing with leaves which are symmetrically located on the opposite sides of the stem. The stems are hairy and can be up to 30 inches long in extreme examples.
Brazil pusley is an aggressive native which will colonize easily in sandy soils. Once established with its deep and secure taproot, it is difficult to completely remove and eradicate.
Unlike Florida pusley, Brazil pusley is a perennial. Its roots penetrate into the subsoil, making it difficult to remove completely.
The leaves can be almost smooth to rough on both the upper and lower surfaces. They may reach 2.5 inches in length and tend to be oval to elliptical shaped.
The blooms are usually white but can occasionally be pink to lavender. The flowers emerge at the end of a head-like cluster which potentially can produce 20 or more blooms.
These plants bloom most months of the year, but they are killed by heavy frost and extreme sub-freezing weather. The blooms usually produce three nutlets covered with wart-like bumps and are the genesis of the next generation.
The nutlets are spread by animals and water flow from heavy rains. They may be unintentionally scattered by mowing or transported on equipment to new sites.
Brazil pusley is frequently found in sandy soils which are common in panhandle Florida. The plant is a tenacious competitor for soil nutrients and space on agricultural lands, roadsides and lawns.
The scientific name, Richardia brasiliensis, refers to Richard Richardson, a wealthy 18th century English physician and botanist. The term brasiliensis relates to its frequent appearance in Brazil.
Richardson practiced medicine in northern England but had studied botany in Holland during his formative years. He had a particular interest in mosses and lichens, but he also focused on vascular plants such as Brazil pusley and is credited with cataloguing this species.
He corresponded widely with other notable botanists of the day and built the largest contemporary collection of plants at his botanical garden at North Bierley, England. Greenhouses at his estate allowed him to collect and propagate plants from warmer areas.
Brazil pusley is considered native to the southeastern U.S., Central America and northern South America, but has travelled to other locations. This plant has made appearances in Asia and Africa.
Land managers have been challenged to control this native with conventional techniques. Post emergent spraying with herbicides provides minimal to no effect unless the plants are very small.
The most successful technique is the application of a pre-emergent herbicide to suspected infestations, but this chemical will affect other seeds, too. This method is practical for heavily managed areas, but wild sites will continue to produce this aggressive native plant.
To make matters worse, this species hosts some destructive insects. Unfortunately, even modern science has not brought a quick solution to this native problem species.
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