This soft, furry creature is a Forest Tent Caterpillar moth. Every ten years or so, there is a huge increase in the population of the caterpillar stage of this species. They are voracious eaters of leaves, especially those of the aspen tree. This population explosion results in widespread defoliation of trees in the north woods. The trees usually grow another set of leaves and most of them do survive. This moth has a wingspan of about 1¼”.