Beet Armyworm Pheromone Trap Captures in Northwest Louisiana, 1999-2012

In Northwest Louisiana, the beet armyworm, Spodoptera exigua (Hubner), is a sporadic pest of cotton.  Since 1999, acreage infested in Louisiana has varied from 172,281 in 2004 to less than 5000 in 2011.  The results reported here are from surveys conducted from 1999 to 2012 to determine the abundance of the beet armyworm in the cotton growing areas of Northwest Louisiana.  Adult populations of the beet armyworm were monitored using 9 pheromone traps (green bucket style traps) located adjacent to cotton fields from northern Caddo Parish near the Arkansas line to Natchitoches, LA.  Pheromone septa were changed every two weeks and pesticide strips every four weeks.  Traps were checked weekly from April through October each year.  In general, fewer beet armyworm male moths were captured in the southern traps compared to the northern traps.   This may be the result of more cotton acreage being grown in the vicinity of the northern traps compared with the southern traps.  The southern traps were located in more isolated areas with less cotton nearby than the northern traps.