The Orange Underwing Moth, like so many moths, is named after its appearance - its bright orange underwings, clearly shown in these photos. It's not always so obvious, as they tend to tuck the bright coloured underwings under their dull forewings. It is very similar to the Light Orange Underwing, which has darker forewings with much fewer white patches. This moth flies during the daytime and is a woodland moth. The caterpillars initially feed on birch catkins, and then on the new leaves.