[1] The adult fall webworm has a wingspan of approximately 30 mm and is generally white-colored, although some individuals may have dark-colored marks.

[3] Introduced to what was formerly Yugoslavia in the 1940s (firstly recorded in 1949[4]), it now has occupied probably its entire range in Europe from France to the Caspian Sea in the east as well as penetrated into Central Asia: Turkmenistan (from 1990 to 1993), Uzbekistan (Fergana valley from 1996 to 1997), Kyrgyzstan, and southeastern Kazakhstan.

[1] One generation per year emerges in the northern part of North America, with larvae appearing in late summer through early fall.

[8] The adult is mostly white in the North America regions, but in the south it may be marked with black or brown spots on the forewings.

Additional host plant examples include madrone (Arbutus menziesii Pursh), mulberry, ailanthus, American sycamore (Platanus occidentalis L.), and Asian white birch (Betula platyphylla).

[2][11] For example, for an insect that needs energy for processes like dispersal or diapause, consuming plants that provide a lot of carbohydrates could be beneficial; for a female insect that is producing eggs, consuming plants that provide a lot of protein could be beneficial.

[13] Groups of larvae live in self-created large webs that are found on tree branches.

Some examples of protective behavior or defense are shaking and jerking together, repellant scent, and irritants on hairs or spines.

[2][16] Due to this, the fall webworm (which is an ectotherm) is able to maintain a warm temperature of about 40-50 °C, which allows the larvae to grow and develop faster.

[17][18] There are many predators of the fall webworm, such as Monomorium minimum, Vespula spp., Coleomegilla maculata, and Rogas hyphantriae.

[23] The fall webworm’s interaction with humans is important because of how adaptable this species is, which is one of the main reasons that it spread so widely across the world.

[2][25][16][26][3] In addition, the fall webworm tends to create many webs or defoliate plants in places that humans spend time, such as recreational areas and parks; fall webworms tend to create their webs on branches and therefore defoliate parts of the tree that are very visible and draw attention.

[2][3][16][25] There have been methods with trying to control this organism, such as physical removal or chemical methods; however, there are some issues with these options because physical removal can be challenging with certain types of trees (based on factors like how tall the tree is, what its function is, where it is located), and the side effects of chemicals (such as important pollinators dying and therefore not being able to perform their functions).