* Cave GL, Randall-Schadel B & Redlin SC (2008) Risk analysis for Phytophthora ramorum Werres, de Cock & Man inβt Veld, causal agent of sudden oak death, ramorum leaf blight, and ramorum dieback. US Department of Agriculture, Animal and Plant Health Inspection Service, Raleigh, NC.
* Davidson JM, Werres S, Garbelotto M, Hansen M & Rizzo DM (2003) Sudden oak death and associated diseases caused by Phytophthora ramorum. Plant Health Progress 4(1), 12.
* Yee WL, Goughnour RB (2005) New hosts of western cherry fruit fly, Rhagoletis indifferens (Diptera: Tephritidae), and their relationship to life history characteristics of this fly. Annals of the Entomological Society of America 98, 703β710.
------- confirmed host (as Rhamnus purshiana)
* Yee WL, Goughnour RB (2008) Host plant use by and new host records of apple maggot, western cherry fruit fly, and other Rhagoletis species (Diptera: Tephritidae) in western Washington state. The Pan-Pacific Entomologist 84, 179β193.
------- rare host (as cascara).