The White-marked Tussock Moth is a common native of North America, living throughout the eastern U.S. and Canada. The caterpillars feed on a range of host plants including birch, cherry, apple, oak, and even some coniferous trees like fir and spruce.
White-marked Tussock Moths produce two generations each year. The first generation of caterpillars emerge from their eggs in spring, and feed on foliage for 4 to 6 weeks before pupating. In two weeks the adult moth emerges from the cocoon, ready to mate and lay eggs. The cycle is repeated, with the eggs from the second generation over-wintering.
Kelly Williams from Northumberland believes that she has discovered vagrant specimens of this exclusively New World species in her garden.
I've attached the photos of the first caterpillar I found (pics 1,2 & 3); on closer inspection/comparison, it may well be the same caterpillar. The tussocks look longer on the one found yesterday (pics 4 & 5) and darker in colour but this could be because it is maturing. I'm not sure, although it has inspired me to invest in a couple of butterfly and moth books so I can investigate a little more.
The pictures of the new one aren't fantastic but I'll get some more this afternoon. It was again found on the patio salix I have growing in a pot in my back yard.
I live in Lynemouth village in Northumberland, and only moved into the property last October so this is my first spring/summer here. The previous owner had nothing in the way of plant life in the yard that I can ever recall, as it was my friend's, father's property for over 35 years. Thanks for your time.