Spotted lanternflies go through several stages of growth after hatching from eggs. The first stages are called nymphs, which are incapable of flight.
Young nymphs are black with bright white spots and are roughly the size of a pencil eraser. The next stages of growth are similar, but the nymphs become larger.
Prior to adulthood, the spotted lanternflies is vibrantly red with distinct patches of black and equally distinct bright white spots.
The adult spotted lanternfly is about 1" long. Adults have gray wings with black spots. When the spotted lanternfly opens its wings, it reveals a bright red underwing.
The spotted lanternfly adult is approximately 1" long and 1/2" wide at rest. The forewing is grey with black spots and the wings tips are reticulated black blocks outlined in grey. The hind wings have contrasting patches of red and black with a white band. The legs and head are black; the abdomen is yellow with broad black bands. Immature stages are black with white spots, and develop red patches as they grow. (Pennsylvania Dept. of Agriculture)
Spotted lanternflies live through the winter only as eggs. Adults lay eggs in masses in the late fall on trees, under bark, posts, lawn furniture, cars, trailers, outdoor grills, and on many other surfaces.
Despite the name, Spotted Lanternflies don’t fly, they jump. The Spotted Lanternfly is a notorious hitchhiker and will lay egg masses anywhere they can, including campers, bikes, tires and tire wells, trailers, and anything else that provides a solid surface.
Where to look for the spotted lanternfly?
SLF can be found on a wide variety of host plants and lay eggs on almost any tree.
Young nymphs can be found in numbers, usually on new plant growth, do not yet fly but can jump long distances, are black with white dots, and are smaller than half an inch.
Adults prefer to lay eggs and are commonly found in high numbers on Black Walnut and Ailanthus trees (aka tree of heaven).