Roseau Cane Scale on the Delta

A small insect, or scale, known as the Roseau Cane Mealy Bug has decimated thousands of acres of Roseau cane in southern Plaquemines Parish and continues unabated.  The scale, native from China and Japan, has been identified as Nipponaclerda biwakoensis, commonly referred to as Phragmites Scale or Roseau Cane Mealy Bug. It has had severe effects on the dominant vegetation of the Mississippi River Delta. The rate at which it seems to be expanding and the severity of its impacts is alarming.

Roseau cane is a tall wetland grass that helps protect Louisiana’s bird foot delta.  More than 100,000 acres of Roseau cane dominated wetlands in the Mississippi River Bird Foot Delta has been affected by the scale as biologists continue to look for ways to stop its spread.  Unlike some marsh vegetation, Roseau cane stands up well to tropical storm events. It is one of the most erosion-resistant marsh plants on the bird foot delta. It also assists in building land by trapping sediment from the Mississippi River. The loss of it could lead to even more rapid land loss in the delta, turning what is now marsh into open water.

What also concerns biologists is that the scale could impact agriculture crops such as sugar cane and sorghum, according to Dr. Rodrigo Diaz, Assistant Professor in LSU’s Department of Entomology. He said it could have significant economic impacts to agriculture crops and native vegetation. 

Presentations by Leading Biologists from LSU and LDWF


Roseau Cane Scale Impacts on MS River Delta, D. Todd Baker – June 14, 2017 Biology and Ecology of the Roseau Cane Scale Rodrigo Diaz, LAWF Roseau Cane and Herbivory on the Delta Jim Cronin, LSU
Development of an integrated management program for control of the roseau cane scale, Rodrigo Diaz, JimCronin and Blake Wilson 

Photos of the Scale and its Damage





Video and B-Roll