Identification: How do I treat a large Arbutus tree with brown spots on all the leaves?

How do I treat a large beautiful Arbutus Tree covered in leaves with brown spots?

 

I am a fan of arbutus (madrone) - an unusual broadleaf evergreen that are
1. Unique to this part of Canada
2.extremely picky about being moved / transplanted
3. Wood crafters like the untouched log lumber should you (Heaven forbid) cut the tree down

careful - the leaves that naturally fall can be very slippery even in the dry season BC Coast so do keep it raked up

I have a few small arbutus (again - I am very keen) and sometimes a branch off the main trunk decides to wilt and die off

I just go with it and use the cut branch (no leaves remain) to hold up my summer lilies etc

also a few decades ago there was a distinct die-off of arbutus in SW BC - I don’t know the specific disease

perhaps @Garry Oak on the island has suggestion for us all

 

See this old UBC Forums thread Douglas Justice contributed to in 2005:

https://forums.botanicalgarden.ubc.ca/threads/arbutus-tree.547/

This article could be helpful too:

https://depts.washington.edu/hortlib/collections/madrone/ch07_el.pdf

Arbutus trees continue to die at a steady rate in my neighbourhood. There was a magnificent old tree on the property below us which I used to comment about to my husband that it was the most perfect Arbutus I'd ever seen. The leaves were absolutely flawless; no clusters of brown leaves that I notice as the first sign that a tree is doomed. Then the neighbour who owned the perfect tree decided to cut off a huge branch - maybe a foot in diameter - and that poor thing was completely dead within the year. Obviously it succumbed to a different pathogen than the one we normally see around here which can take years to finally weaken the tree to point that it dies.

Cutting off those clusters of brown leaves does seem to slow down the rate of decline but most of my Arbutus trees are far too tall for me to do that and hiring an arborist would be prohibitive. Maybe being a bit of a fatalist here but it seems that once a fungus takes up residence in an Arbutus, there's not much that can be done.

Margot

 

Really hoping there's a bit more hope than you shared