The larvae (caterpillars) of the “Oak Processionary Moth” (Thaumetopoea processionea) predominantly feed on oak, but also hornbeam, hazel, beech, chestnut and birch.
Although the leaf damage can be servere, Oak Processionary caterpillars pose a serious risk to human health. The caterpillars are covered in bristle-like hairs containing a chemical toxin. Human contact with the hairs can provoke allergic reactions manifested as skin rashes, conjunctivitis and respiratory problems such as pharyngitis and asthma. Health problems can occur even if the larvae are not handled as the hairs break off readily and are dispersed in air currents. Abandoned caterpillar nests contain shed caterpillar skins, pupal.
The likelihood of human contact is increased as OPM are most abundant on urban trees, along forest edges and in amenity woodlands.
Moth populations are well established and increasing in northern Europe in response to climate change. OPM is spreading in London and has been detected further afield and as far North as Sheffield.
So what is the solution? The biological insecticide “Dipel DF” contains naturally occurring bacteria which is highly effective at controlling caterpillars. Dipel DF is approved for use in 190 different crop types including vegetables, fruit, forestry, and amenity situations.
Although lethal to caterpillar, Dipel DF is non toxic, biodegradable and safe to other insects, fish, animals and humans and permissible in organic situations. Once a caterpillar has ingested Dipel DF, it stops feeding in minutes and dies within 24-72 hours.
Dipel DF is available to purchase at www.progreen.co.uk
A 0.5kg packs is sufficient to treat 6666m2 (1.66 acres). Full instructions and a safety data sheet are available to download at the above website.