The East Asia box hedge caterpillar is spreading fast. There are a lot in the south east of england but it’s spreading north rapidly.
The box caterpillar is greenish and yellow. It has a large black head. They are 1.5cm to 2cm long.
You may see pale yellow eggs on the back (underside) of the leaves too. These develop a black spot.
The devastation they cause however is the real identifier, with webbing around the base of stems and all the greenery eaten away. It can eat an entire hedge very quickly, within 3 days you’ll notice significant impact to your hedge and then within 2 weeks the entire hedge (assuming a large hedge or multiple box hedges) will be eaten.
The moths have wings that have a dark brown border and are around 4cm in width.