Pressure washing costs in Allentown

Allentown met the spotted lanternfly early. The insect was first found in Pennsylvania in Berks County in 2014. In October 2016, the state widened its quarantine zone to take in the city after an isolated pocket turned up here.

For your house, the trouble is what the bug leaves behind. Lanternflies feed on sap and get rid of the excess as a sugary liquid called honeydew. Penn State Extension says it builds up below the feeding insects, and on sunny days you can see it falling from trees like a light rain. Sooty mold often moves in on it, and the stains turn up on decks, patios and cars parked under infested trees.

The bug keeps a calendar. Adults come out in July and stay active until hard freezes kill them. Eggs go down from September to December, on trees, decks, houses, rocks and outdoor gear, and they hatch from late April to June.

That timing matters for a wash. If a sticky black film builds up on the deck or patio under your trees in late summer, honeydew is one suspect, and the insects that made it can keep dripping until the first hard freeze.

A fall wash is a good time to look over deck boards and siding for egg masses, too. The state Department of Agriculture says destroying the egg masses helps bring the population down.