Voung men, employed by the Civilian Conservation 

 Corps in the 1 930s, were set to work pulling 

 Ribes bushes, the alternate host to the rust, in an 

 attempt to eradicate the disease. Photo courtesy of the 



National Archives. 



Blister rust is aptly named, 

 causing blister-like swellings 

 and eruptions of yellow 

 spores on branches and 

 stems of five-needle 

 pines. Once the entire 

 circumference of the branch 

 or trunk is infected, the 

 portion above dies. 



White Pine Blister Rust: White pine blister rust was first found in the West in the 

 summer of 1921. The disease was identified on eastern white pine seedlings, imported 

 in 191 Ofrom France and then planted at Point Grey near Vancouver, British Columbia. 

 By 1 922, rust infections had been discovered at many points along the Washington 

 coast from the Columbia River north well into British Columbia. From that small begin- 

 ning, this rust spread and infected all species of white pine found in the Pacific North- 

 west, including western white pine, sugar pine, and whitebark pine. 



One early attempt at control was to eradicate the alternate host, currant or gooseberry 

 plants fl^bes spp.). Many men were hired by the Civilian Conservation Corps (CCC) 

 and Works Progress Administration (WPA) during the Great Depression years to pull 

 and burn ribes bushes in Northwest forests. As recently as the early 1 950s, many 

 students worked their way through college pulling ribes. The cost of this program was 

 almost $100 million nationwide, with $62 million spent in the West. 



By 1 956, the rust had spread to most of the white pine forests in the United States, 

 and control efforts turned from ribes eradication and quarantine to managing the 

 disease, recognizing that it had now become a permanent part of many western for- 

 ests. Management concentrated on developing pines resistant to the disease and 

 trying to return white and sugar pines to their previous roles in forested ecosystems. 



Overview — 17 



