The brown tail moth can be a common sight in Southend-on-Sea. From May through to early July, the Brown Tail will typically be at caterpillar stage, often feeding in large numbers.
If the caterpillars come into contact with people, the hairs from the caterpillar can cause a painful skin rash.
Brown Tail Moth Caterpillars have been found in some isolated areas within the City. This page gives general information on how you can help limit its spread and prevent you and your family possibly suffering from the painful rash that the moth's caterpillars can cause.
Although the caterpillars prefer hawthorn and blackberry, it will eat any type of bush. In big numbers these caterpillars can cause the entire de-foliage of trees and bushes and can be a problem for gardeners. Despite this, trees and bushes affected will almost always survive.
Where the population is being seen to spread to neighbouring council owned sites, we may carry control methods to try to contain the population either by cutting out the nests or vacuuming the caterpillars. In both cases the caterpillars are destroyed. Sometimes it might not be practically possible to control the population. Read below for advice on private property.
When are they active?
The caterpillars become active in the spring. During March, caterpillars can be found in their winter tents. By April the caterpillars have begun to emerge from their tents and begin to feed.
They expand the area of defoliation around their winter tents during May so that by June the caterpillars have moved away from the tents and become solitary. They spin a cocoon and pupate, at which point they will disappear before emerging as adult moths emerge in July/August when they mate. Moths are important pollinators.
Females lay eggs near the tip of shoots and then they spin a tent at the end of the shoot in readiness for winter.
What do they look like?
These caterpillars are between 7mm and 38mm in length (depending on age), dark brown in colour with a distinctive white line down each side.
The whole body is covered in tufts of brown hairs and two distinct orange/red dots are noticeable on the caterpillars back towards the tail. The caterpillars carry spiked and barbed hairs, which can penetrate skin, causing an irritant reaction.
For asthmatics and hay fever sufferers, it is important that the hairs are not inhaled as these may cause breathing difficulties.
What should I do if I have an infestation?
Where these caterpillars are found on private property the council is unable to take any action to remove them. Local pest control companies are available and can remove the tents or use chemical control methods.
Great care should be taken to avoid touching the caterpillars and in cases of large infestations, it would be wise to keep windows closed to prevent caterpillars entering into your house.
The only certain way of eliminating any infestation is by pruning out and burning the tents during the autumn/winter period, when the caterpillars are inside them.
During the summer months when the caterpillars are active, contact chemical sprays may give some immediate control, but as only some 10% of the caterpillars leave the confines of the tents at most times, this is not a totally effective option.
It is possible to self-treat for these caterpillars, but there is a risk of irritation so precautions must be taken.
If you are uncertain of the chemicals to use and are not aware of the safety and application requirements, do not attempt to use chemical control. If you are happy to undertake this, various pesticides are available from most good garden centres where further advice can also be sought.
It is important to closely follow the manufacturer's methods of application and to use protective clothing.
If attempting to prune out winter tents:
- wear appropriate protective clothing, which will ensure that there is no contact between the irritant hairs and the skin. If possible garments should be made tight at the wrists and ankles.
- use gloves, a hood, goggles, boots and a dust mask to ensure that bare skin is covered
- if you are using a ladder, make sure that it is fit for purpose and that someone can hold it steady
- the caterpillars emerge particularly during warm weather and can be treated when they are out of their nests using a chemical spray. The most suitable and widely available chemical is called a Pyrethoid and is sold under various names at garden centres and chain stores. It is not effective when the caterpillars return to their nests in the evening and during bad weather. At these times it is much better to physically remove the nest using secateurs to cut them and drop them into a plastic bag. The bag should then be sealed and either burnt, if it is safe to do so, or sealed in a second plastic bag and put in your bin
You are advised not to attempt to deal with an infestation if you are:
- asthmatic
- suffer from hay fever
- have sensitive skin or eczema
- do not have adequate protective clothing
- not comfortable working at heights
What if I get a rash?
If you are affected, the rash will be similar to severe nettle rash. The discomfort should subside after a few hours. It is best not to scratch at rashes and certainly inadvisable to touch the caterpillars.
A warm bath, with the application of calamine lotion or antihistamine cream may ease the itching.
If any other symptoms are experienced or the irritation persists, medical advice should be sought without delay. Please visit NHS.UK for further allergy advice.
If you have any queries, please email parks@southend.gov.uk