This beautiful moth was on the yellow onion plant that I had grown from the kitchen. We never thought it was a moth until we identified it. Below you will see a photograph from bugguide.net of the larva of this moth. This moth belongs to the genus Atteva and it is the only species of this genus that lives in North America! According to bugguide.net:
Larvae live in communal webs (3). One generation a year (4). The main larval food plant (Ailanthus altissima) is also known as Tree of Heaven, Stinking Sumac, Copal Tree, or Varnish Tree, and occurs throughout most of United States and southern Canada, often planted as an ornamental in urban areas. The tree is native to Asia, and is an invasive species in North America, but the moth is native, and its range has increased, presumably, since the introduction of the tree.