Brown Marmorated Stink Bug
The brown marmorated stink bug, Halyomorpha halys (Stål), is a voracious plant-eating pest that is damaging fruit, vegetable, and ornamental crops in North America. BMSB was accidentally imported from Asia to North America in the late 1990s. The earliest sightings were in Allentown, PA. This bug quickly became a nuisance pest, overwintering in homes, office buildings, sheds, warehouses and in wooded areas. With few natural predators and an abundance of food sources, the invasive insect spread quickly. By 2004 the stink bug was widely identified on farms and in forests. In 2010, the invader caused catastrophic damage in many mid-Atlantic states, with some growers of sweet corn, peppers, tomatoes, apples, and peaches reporting total losses that year. In 2011 the stink bug continued to present season-long and significant problems for growers in that region. Sightings and trap captures of BMSB have been increasing in states to the north as well.
Extension scientists in MA have been setting out traps baited with pheromones since 2012, with fairly sporadic, low numbers of captures. In the early years of an area’s invasion, the most sightings and captures come from private dwellings, sheds, roadsides, and automobiles. The insect populations build up for a few years in the woods, feeding on seeds and fruits (any source of carbohydrate or protein) and move into crop lands later in the season as they exhaust food supplies where they are. In Fall 2012, a few were trapped in peaches in Hampden County, MA, near Springfield, and others were sighted near-by in apples. In May 2013, using an improved pheromone being developed by the USDA, entomologists in the NY Hudson Valley trapped higher numbers in the edges of woods next to tree fruit. In MA we expanded our network of trapping sites (to about 17 sites across the state each year) and have been using the improved pheromone. This has been a joint effort of the UMass EIP project, Barstable County Extension, MDAR, and private crop consultants. In 2013 the total BMSB trap captures and positive ID sightings were 22, followed by 27 in 2014, and 37 in 2015. So far in 2016, 17 have been reported. During the same time period, the numbers have been higher in CT and in the Hudson Valley. At some orchards, insecticide applications have been made against this bug. So far we have been spared in MA.
Trap captures will be a good indication of BMSB activity in the environment of the orchard edge, but they are not yet reliable indicators of insect damage in the crop. Direct observation of bugs and feeding damage is necessary for that. Scouting in peaches and cherries (and later in apples, sweet corn, peppers) at the wooded edges of fields is recommended. The robust qualities of BMSB and the ecological niches in which they are thriving here make them very hard to kill with reduced-risk insecticides. A return to harsher chemicals has been necessary in many agricultural settings. An extensive team of scientists is studying stink bug behavior in order to deploy sustainable controls such as traps and lures, biopesticides, and natural enemies against BMSB (see the StopBMSB website).