Sycamore lace bug
About sycamore lace bug
Sycamore lace bug (Corythucha ciliata) (SLB) is a native North American insect that feeds only on sycamore and plane trees (Platanus spp.). It was first recorded in Australia at Sydney, NSW in March 2007.
Adult SLBs are about 3 mm long and white in colour. They have a lace-like pattern on their wings, head and thorax.
SLB adult from above (left) and underside view (right)
Immature SLBs (nymphs) are smaller than adults and have light and dark bands or patches.
Several consecutive years of severe SLB damage, combined with other stress factors, may kill host trees. Heavy infestations are more common in urban areas than in natural settings and damage is more severe during dry weather.
The bugs overwinter as adults, either under loose bark of the trees, or in nearby cracks and crevices. They are extremely tolerant of cold weather.
SLB occurs throughout the eastern USA and eastern Canada and is common in most of the places that sycamores grow in Florida. It was discovered in Italy in 1964 and has since spread through much of southern and central Europe. In northern Italy, SLB is associated with two fungi which, in combination with the bugs, cause decline and death of the trees. It is suspected that the bugs may serve as vectors for these fungi.
The major host of SLB overseas is the American sycamore tree, Platanus occidentalis. Other Platanus species may also be affected. SLB has been found on a range of Platanus species in NSW.
SLB feeds on the undersides of the leaves, initially causing a white stippling that can eventually progress into chlorotic or bronzed foliage and premature senescence of leaves. In cases of severe infestations, trees may be defoliated.
Early symptoms of SLB on a plane tree (Platanus sp.) (left) and later symptoms (right)
All life stages occur together on the undersurfaces of the leaves, which become marked with black varnish-like excrement spots and cast skins of previous developmental stages.
Although the flying wings of SLB adults are very delicate, adults have been found to be very mobile. Supported by wind they can fly over many kilometres. However, the majority of long distance distribution results from human activity.
In NSW, SLB has been found across the Sydney Central Business District, as far north as Brookvale and south to Wollongong. Damage is relatively severe, with very large numbers of lace bugs present in all trees inspected.
The first Victorian detections of sycamore lace bug (SLB) were made in several towns in the north-east of the State in March 2012.
SLB is not a declared pest in Victoria and responsibility for its control rests with affected land managers, both public and private.
A variety of insecticides and application methods can be used against SLB - please refer to the Australian Pesticides and Veterinary Medicines Authority website.
In North America, there are several parasites and pathogenic fungi that attack SLB, but these seldom reduce populations enough to prevent significant damage to sycamore trees
If you suspect you may have found SLB on public land, contact the local council responsible for the location.
Detections of sycamore lace bug on private land are the responsibility of the landholder.
Halbert, S.E. and Meeker, J.R. 2001. Sycamore Lace Bug, Corythucha ciliata (Say) Insecta: Hemiptera: Tingidae