14th July 1999

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A young Coleraine couple has uncovered colonies of a mystery bug in their garden that they say is the size of a spider but which at night uses its massive wings to take flight.

Environmental experts at the University of Ulster have identified the problem and say the species, which is common to the forests of central Europe, is so rare to Northern Ireland that they have seen it only once in the last 25 years.

The experts were first alerted to the problem after seven year old Jack Ferris discovered an unusual amount of wasps in the garden of the family home at Gorgranagh Drive.

When Jack's father, Peter, went to investigate the problem he was left with more questions than answers:

"The wasps were not at all aggressive and would just fly around us aimlessly. When I looked at the bark of the pine trees they appeared to be covered in black dots. The University experts have told me that these are aphids. They are slightly smaller than a spider and fly about at night."

Dr Keith Day from the University's Environmental Research Group is a specialist on greenfly and other inspects. He says the bug is an unusual aphid, or greenfly, which is feeding on plant sap in the bark of the family's ornamental firs:

"The aphids are large, brown and gather in huge colonies on tree trunks and branches, where they produce large amounts of sugary honeydew. As this rains down on the grass and other plants it encourages a sooty mould to grow.

"The honeydew is attracting huge numbers of wasps. It ferments rapidly and the wasps are getting intoxicated."
The common name for the aphid is Large Fir Lachnid. In Europe similar species on Spruce trees are used to attract wasps for the production of forest honey - honey produced in forests is often considered to have outstanding nutritional properties.

The Ferris family garden is one of the most mature in the area, with a number of well-established trees. This may partially explain the problem:

"The situation may have also arisen through a lack of normal woodland predators in the suburban environment and by the recent warm weather," explained Dr Day.

Now that the source of the problem has been established, defestation experts are due to be called in shortly.

For further information, please contact:

Press Office Department of Communication and Development
Telephone: 028 9036 6178
Email: pressoffice@ulster.ac.uk