They are common on 

 Douglas-fir, white fir, 

 lodgepole pine, Jeffrey 

 pine, western hemlock, 

 and mountain hemlock 

 and less frequent on pon- 

 derosa pine and other 

 species. 



Trees infected with 

 dwarf mistletoes have 

 been removed during 

 timber harvest and stand 

 cleaning in some portions 

 of the region. Many ar- 

 eas, however, probably 

 have more dwarf mistle- 

 toe-infected trees now 

 than they had before fire 

 exclusion. Where ground 

 fires were once frequent, 

 higher proportions of in- 

 fected trees were killed 

 because ground fuels 

 and large brooms carried 

 fire into the crowns. In 

 many areas with selective 

 harvests, healthy trees 

 were removed, leaving 

 behind infected trees, or 

 heavily infected trees 

 were removed and infec- 

 tion intensified in lightly 

 infected trees when those 



Root Disease 



Pon-Orford<edar (green) and Port-Orford<edar root disease (red) have 

 been mapped on the Siskiyou National Forest. The disease is found in 

 wet areas along streams and in riparian areas. Source, usda Forest Service surveys. 



trees were exposed to increased light. 



Port-Orford-Cedar 

 Erotic pest kills Port-Orford-cedar on wet 

 sites — ^Port-Orford-cedar grows from Just north 

 of Coos Bay, Oregon, into northern California 

 in a narrow coastal strip. It grows on a wide 

 variety of sites including streambanks, bogs, 

 coastal sand dunes, deep productive soils, and 

 dry sites. Port-Orford-cedar needs a consis- 

 tent water supply and is an important species 

 in riparian ecosystems. Its snags and logs are 

 long-lived components of terrestrial and 

 aquatic wildlife habitat. It has important cul- 

 tural value to the indigenous people of north- 



western California. Although its domestic 

 market is limited, for decades the export mar- 

 ket for Port-Orford-cedar has been substan- 

 tial, making it one of the most valuable spe- 

 cies in North America. 



In 1952, an introduced disease caused by 

 a waterborne fungus, was reported within 

 the native range of Port-Orford-cedar at Coos 

 Bay, Oregon. Cedar mortality soon became 

 conspicuous in coastal towns and along ma- 

 jor roads. The fungus is now present 

 throughout much of the range of Port- 

 Orford-cedar. Infested and healthy Port 

 Orford-cedar are intermingled. Where the 

 disease has been present for several decades. 



Oregon — 4 1 



