Year 12 | 28 January 2020 | TO ENTER | TO REGISTER

The silent but innocuous invasion of shield bugs

Against these tiresome insects, which are innocuous but emit irritating stinks, we have to provide for insect screens and vacuum cleaners

In the last weeks a number of shield bugs have it in for many houses and flats in Italy. The experts advise against the use of pesticides inside houses or along external walls since these products are ineffective against such bugs.

These bugs are mainly of two species: the Western conifer seed bug (Leptoglossus occidentalis) and the Elm bug (Arocatus melanocephalus). As a matter of fact, because of the climate change, these species greatly enhanced their diffusion in our territory.

L. occidentalis, known as the Western conifer seed bug, is an invasive species coming from the North America. The young and adults specimens eat conifer cones but this can cause damages only to the conifer hoods for seed production or to pine nuts or pistachios cultures. During the fall the adults leave the plants to winter in hot and dry places.

A. melanocephalus, known as elm bug, is a species that appeared on the Italian territory in the second half of the nineteen century. This heteropterus does its biological cycle on different plants of the Ulmus family and, at the end of the development, adults tinker in natural refuges or in houses where they spend the summer and the winter time. Because of both the young and the adult specimens eat the elm samaras, there are not known damages to plants.

“Both the bugs during the winter time do not eat or reproduce but survive in a dormant condition” say Cristina Salvadori and Federico Pedrazzoli of the plant pathology unit of the Technology transfer center of San Michele dell’Adige, Italy.

However, people that live close to pine or elm woods can implement some precautionary measures to prevent the entrance of these bugs in their houses. This can be done by a better frame insulation or by the shielding of windows by insect screens. The adult specimens can be easily removed from the houses by using a vacuum cleaner in order not to elicit the production of stinking substances.

Moreover, in the future could also be useful the spotting of specific repellents that can be used in the most critical months.

Source: Iasma

by Ernesto Vania
07 december 2009, Technical Area > Science News