2011 Annual Report 1a.Objectives (from AD-416) The objectives of this cooperative research is to develop mass rearing methods for the Arundo wasp, a key candidate biological control agent of the invasive weed, giant reed, Arundo donax. 1b.Approach (from AD-416) Greenhouse rearing facilities at the USDA-APHIS-CPHST Biological Control Laboratory at Moore Airbase (Edinburg, TX) to develop rearing techniques for the Arundo scale and/or other arundo biological control agents. 3.Progress Report Arundo scale were imported from 13 locations in Spain and France for processing in the quarantine facility. University of Texas at Pan American student workers assisted ARS staff in removing the mature female scale from the field-harvested rhizomes into gelatin capsules for isolation of 1st instar crawlers. Crawlers were released onto local rhizomes grown in 60-gallon tanks. Rearing studies showed that scale survival was higher on rhizomes grown in sub-irrigated vermiculite overlain with pea gravel as compared to surface irrigated mixed gravel and river silt. Studies are underway to determine the survival of scale released on field planted, sub-irrigated rhizomes. The ADODR and cooperator are in contact via email and phone on a weekly basis.