Laminated root rot is a disease caused by a naturally occuring fungus called Phellinus weirri (or P. sulphurascens), found through many ecosystems in the Pacific northwest. It can cause the death or decline of evergreen species such as Douglas-fir, grand fir, Sitka spruce and Western Hemlock. In addition to impacting the health of the Forest, root rot also poses a risk to public safety by increasing the number of hazardous trees near trails, and exacerbating wildfire conditions by increasing fuel. Root rot was first identified as a forest health concern in 1999, and after extensive research and public consultation, root rot management activities began in the Sunnyside Acres Urban Forest in 2003.

 

The disease spreads by root contact at the rate of over 100cm per year.  The City of Surrey's management plan called for the felling of trees near afflicted areas to create a ten metre quarantine belt; the goal was to ensure that the roots of any diseased trees would not contact the roots of any remaining non-infected healthy trees.  These quarantined areas were then replanted with deciduous trees, such as alder, which can act as a natural "sanitizing" agent against the fungus. Unfortunately, prior to the establishment of the Urban Forest most alder trees were removed for firewood.

Laminated root rot continues to pose a significant threat to the health of Sunnyside Acres Urban Forest.  The efforts to try and contain the disease were not successful and the new cases of laminated root rot have been found outside of the quarantine belt that was created.  

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To guide future management practices of Sunnyside Acres Urban Forest, especially regarding challenges like laminated root-rot, our society view affirms the original preservation principles of Sunnyside Acres:
 

“Aside from invasive species removal and compensatory planting of native species, allow nature to take its course with minimal intervention implemented only for public safety reasons.” 

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We recommend no further destructive intervention to try and further quarantine the disease; instead, nature should be allowed to take its course, with action only for public safety.  

Residents can continue to enjoy the forest as a living, evolving ecosystem as it was meant to be - a natural story of adaption over the years.