They are huge as can be seen in the picture with my hand as a measure, about 5 inches and as fat as my thumb.
The color is unmistakable and so easily recognizable.
Outbreaks of these caterpillars can cause defoliation of shrubs.
As I often find the larvae but not the moth itself, I have brought two home but this takes a long time and the moths will only emerge next summer.
For more information, please click here as this is a most interesting critter. :)