Syngrapha celsa, the plain silver Y or western conifer looper, is a moth of the Noctuidae family. It is found in from British Columbia to California, Idaho, Nevada, Arizona and New Mexico. The wingspan is 34–38 mm. Adults fly from July to September depending on the location. The larvae feed on Abies lasiocarpa, Abies grandis, Abies concolor, Picea egelmannii, Picea glauca, Pinus monticola and Tsuga heterophylla.