Refining rates and treatment sequences for cogongrass (Imperata Cylindrica) control with imazapyr and glyphosate
Cogongrass (Imperata cylindrica (L.) Palisot) is an aggressive invasive plant on all continents and has been spreading northward in the Southeast's Gulf Coastal Plain and into Florida for 80 years. It spreads by prolific windblown seeds and with movement of infested soils while infestations increase in size and become more dense by rhizome spread. Much research has been reported worldwide on cogongrass control, while especialiy crucial in our region has been that performed by the team led by Dr. Donn Shilling at the University of Florida. The research by Schilling's teamhas found that the mosteffective forestry herbicides for cogongrass control are Accord (glyphosate) and Arsenal (imazapyr); the most effective application times for both herbicides are in late summer; and that the total application volume is best at 5 gallons peracre (gpa) for Accord and 25 gpa for Arsenal. All research has shown that repeated applications are needed for eradication.