Houser, J.S. 1908 The more important insects affecting Ohio trees.. Bulletin of the Ohio Agricultural Experiment Station 194: 173-181.

Notes: Lepidosaphes ulmi, Aspidiotus perniciosus, Chionaspis furfura, A. ancylus, Aulacaspis rosae, Ch. americana, Pulvinaria innumerabilis, Eulecanium nigrofasciatum, Gossyparia spuria, E. tulipiferae, Ch. pinifolae, Asterolecanium variolosum and Chermes pinicorticis.