Brown Marmorated Stink Bug Spreads in Sacramento County

(WB) - New finds of brown marmorated stink bugs (BMSB) (Halyomorpha halys) in Sacramento County have been reported by UC Cooperative Extension (UCCE) Sacramento County viticulture and pomology farm advisor Chuck Ingels. Finds were confirmed at two residential properties in Citrus Heights in the northeast county in October 2013, and one was confirmed in December 2013 at an Elk Grove residence in the southern part of the county—within the northern boundary of the Lodi American Viticultural Area.

Ingels previously reported in September 2013 that a well-established population of BMSB exists in a residential and light commercial area in midtown Sacramento covering 42 city blocks that may have been there for one to two years. This is the first known reproducing BMSB population in California outside of Los Angeles County. The recent outlying finds in Sacramento County are on residential properties of people who work in, or frequently visit, midtown or downtown Sacramento. “Anyone who visited this area in summer or fall 2013 (or earlier) may have inadvertently spread BMSB to other regions,” Ingels said in his January 2014 “Tree and Vine Newsletter,” posted at http://cesacramento.ucanr.edu/news/Tree_-_Vine_News/.

The bugs can travel long distances by hitching rides in vehicles, and as stowaways when furniture is moved. As a result, new infestations are commonly found in urban areas. BMSB seeks winter shelter, and large numbers can congregate on outside walls or inside homes. BMSBs migrate seasonally as populations grow and weather warms, most commonly in summer and fall. They are strong fliers, capable of traveling more than one mile a day, with some studies measuring flights of 20 miles and more in one day.

With the Unified Wine & Grape Symposium and trade show scheduled to bring in thousands of wine industry professionals and grape growers to downtown Sacramento next week, Ingels was asked about the possible threat of BMSB spread via individuals who park their cars in the downtown area. “It’s not an issue this time of year, because the bugs are dormant and not moving,” Ingels said. “In summer and fall when the bugs are migrating is when the main threat for spread exists,” he added.

The main Sacramento infestation is bounded by O and V Streets and 11th and 17th Streets. However, 14 other finds of one or more bugs were recorded during Fall 2013 in the downtown/midtown area north or east of the area described above, and one find in Old Sacramento. A map and a list of recorded finds can be accessed through the UCCE Sacramento County website at http://cesacramento.ucanr.edu.

Another infestation was confirmed in fall 2013 in Yuba City in Sutter County (40 miles north of Sacramento) in several commercial buildings, and one or more bugs in the Northern California counties of Butte, Glenn, and Siskiyou. Individual BMSBs were found in Davis in Yolo County in 2012.