Description:
Patch of Aneilima (Murdannia keisak) Weeds.
Murdannia keisak has no common name and is generally known as aneilema from its former scientific name, Aneilema keisak. It is a member of the spiderwort family (Commelinaceae) with weak, prostrate stems 12 to 30 inches long, rooting at the lower nodes, with upturned tips. The alternate leaves taper rapidly from the sheath to a very narrow blade 1 to 2½ inches long. In Virginia the three-petalled, white to bluish-purple, perfect flowers extend from the upper axils in late August to late September.
Habitat:
Found in freshwater marshes and along the edges of ponds and streams, aneilema is associated with rice culture in East Asia. It was probably first brought to South Carolina or Louisiana in rice imported for growth in this country. While the earliest records of existence in the United States date to the 1920s and early 1930s, circumstantial evidence suggests that it could have been associated with our rice industry many years earlier.
Distribution:
Aneilema is found today throughout Asia but is generally considered native to China, Japan, Korea and Tibet. In the United States, it is found in all coastal states from Delaware to Louisiana, and in Kentucky and Tennessee. It is also found in a freshwater tidal marsh in the Columbia River estuary between Washington and Oregon. Initially thought to be restricted to the coastal plain, aneilema is increasing in the Piedmont and Ridge and Valley Provinces of Virginia, Tennessee, northern Alabama and northern Mississippi. In Virginia, it is present in all Coastal Plain counties except the Eastern Shore, most of the central and northern Piedmont, and in Augusta County of the Shenandoah Valley. Aneilema seeds are a favored food of ducks and other waterfowl, which may be an important dispersal vector for the plant.
Distribution Map:
Distribution of Aneilima (Murdannia keisak) shown in Green.
Threat:
The aggressive nature of this plant has now been clearly displayed by its ability to establish itself in freshwater wetlands and crowd out native
Close up of Aneilima (Murdannia keisak)
vegetation by forming a solid mat of vegetation. Even in its native region, this species is a troublesome weed. Not only does it produce thousands of very small seeds, it can reproduce vegetatively.
Control:
Mechanical removal of aneilema is not recommended even when on ground that will support the equipment because remaining stem fragments will root and re-establish the plant. Only a biodegradable herbicide licensed for use in wetlands can be used. Consult an agricultural extension agent or natural resource specialist to determine the appropriate control method for your situation.
