2007 Annual Report 1a.Objectives (from AD-416) Develop control method for tarnished plant bug in cotton based on use of insecticides. Examine the buildup of plant bugs in early wild hosts, movement to other wild hosts or corn, and the subsequent movement of plant bugs from these hosts into cotton. Determine if reducing the number of early-season wild hosts will decrease the number that eventually move into cotton. 1b.Approach (from AD-416) Replicated field experiments will be conducted in which early-season host plants found near corn and cotton fields will be reduced in number by use of herbicides. Plant bug populations found on wild hosts in treated and untreated areas will be measured along with host density and host species composition prior to and after treatment. Numbers of plant bugs found in corn and cotton in treated and untreated areas will be meausred during the growing season. Numbers of insecticide treatments needed to control plant bugs and other pests in cotton fields in treated and untreated areas will be recorded along with other pertinent field data such as cotton variety, yield, irrigation, and fertilizer use. 3.Progress Report This report serves to document research conducted under a Specific Cooperative Agreement between the Southern Insect Management Research Unit, USDA-ARS, Stoneville, MS, and the Louisiana State University, Northeast Research Station, St. Joseph, LA. Additional details for this project may be found in the in-house project 0500-00044-013-00D, "Area-Wide Pest Management of the Tarnished Plant Bug in Cotton in Absence of the Boll Weevil." The research was conducted on commercial farms near Newellton, LA, during 2000-2005. Two areas, a treated and a non-treated area, were established each year. During 2004-2006 the sites were ca. 800 ha. During 2005, the treated site was ca. 1,554 ha and the non-treated site was 2,331 ha. In the treated area, marginal areas near roads, fields, and ditches were treated with the herbicide in March to kill broadleaf host plants of the tarnished plant bug. Weed hosts in marginal areas were sampled for plant bugs prior to and after treatment. Cotton grown in the areas was sampled weekly for plant bugs during June and July. The early season herbicide treatment caused a significant reduction in numbers of plant bugs found in marginal areas of the treated area as compared to the check area. Tarnished plant bug adult densities were low in cotton in the treated and non-treated sites during 2004-2006. During 2005, plant bug densities were high in cotton fields in the non-treated site with nymphs having densities two fold higher in cotton fields in the non-treated site. During 2006, densities of adults were ca. 2.6 fold higher in cotton fields in the non-treated site during early July. Densities of nymphs were 1.1 to 2.2 fold lower in cotton fields in treated site from mid June to late July. Results from the study indicated that the management strategy could reduce plant bug infestations in cotton in the growing conditions found in northeastern Louisiana. Samples of runoff water taken in March 2005 and 2006 after the herbicide application were analyzed for the presence of 2, 4-D and Dicamba, both of which are found in the herbicide used in the treat area. No residues were found. The analyses were performed by ANALAB, Corporate Laboratory, Kilgore, TX, using EPA method 8,151 for the analyses. This agreement was monitored by one conference call and two site visits.