Types of Cedar

• "Cedar" is a generic term that refers to either "true" cedar, wood from the Cedrus genus, or "false" cedar, trees from other genus with strongly-scented wood. The term "aromatic" cedar typically refers to the eastern redcedar (Juniperus virginiana), a false cedar. It does not refer to other false cedar, such as the western redcedar (Thuja plicata), northern white cedar (Thuja occidentalis) and the Atlantic white cedar (Chamaecyparis thyoides).
  
  

Believed Dangers

• Some types of false cedar are believed to be dangerous because they contain aromatic or volatile compounds. The primary irritant is plicatic acid, although cedrene and cardol are also problematic. These compounds can irritate the skin, increase infection rates and cause respiratory tract infections. Birds that have been overexposed to cedar show sign of respiratory tract infections such as sneezing and discharge from the eyes and nostrils.
  
  

Experts for Cedar

• According to the Purple Martin Conservation Association (PMCA), the Environmental Protection Agency and a wildlife toxicologist with the U.S. Fish and Wildlife lab found no data that cedar was toxic or harmful to birds. Nor did the PMCA observe any symptoms caused by the overexposure to cedar in birds exposed to cedar shavings. Claims that eastern redcedar is more toxic than western redcedar have also not been proven and seem unlikely since plicatic acid is most concentrated in western redcedar.
  
  

Experts Against Cedar

• Dr. Richard Evans, a veterinary pathologist associated with the Orange County Department of Public Health, reported in 1994 that that the compounds in cedar have had ill effects on poultry and pet birds. He goes on to say that evidence indicates that cedar may affect reproductive rates and cause cancer after prolonged contact. But those effects were seen in situations with poor air circulation, which is not present outside. Gary Springer, a naturalist with Real Bird Homes.com, is also against using cedar for birdhouses because he feels its effect on birds is unclear. But that could be said about other woods, too.