Basal Root Rot Olive Tree

5te

my 3m olive tree leaves are constantly falling off, few dead branches and bark peeling off in areas. The tree is still grows new leaves.
Could I have basal rot?
 What fungicide treatment do you recommend I put in the soil to help reduce the rot? 
Has anyone used copper fungicide or humic acid?
Anyone has experience in agriculture?
Thanks

Dustyevsky

This is a UK website. What country are you living in? Basal root rot in the UK usually relates to bulbs and corms, not woody trees.

In the UK, fungal diseases called Phytophthora and Honey fungus are problems, but chemicals like copper fungicides aren't available to home gardeners as treatments, so few will have any experience of using them.

5te

Thanks for your reply. I am outside m25 London. Basal rot was suggested to me by a tree surgeon based on this photo I sent. The whole trunk has given way following windy weather and there are always leaves falling off after I sweep it up. 

Has anyone experience something similar with their olive tree? 

Could anyone recommend any good fungicides I can use in the soil? 
Copper fungicide is available online. 

5te

more photos of leaves

Dustyevsky

I referred to the sort of root/stem rots we experience in the UK as listed by the RHS, who also state: "No chemical treatments are available to gardeners for the control of Phytophthora root rot." and "There are no chemicals available for control of honey fungus. If honey fungus is confirmed, the only effective remedy is to excavate and destroy, by burning or landfill, all of the infected root and stump material. This will destroy the food base on which the rhizomorphs feed and they are unable to grow in the soil when detached from infected material."

While true, these statements ignore the possible use of patio cleaners to control fungus and rots caused by organisms in the soil. Technically, it's unlawful to use them for that purpose. I suggest going back to your tree surgeon for more specific advice.

Now you have included a picture and location, two other things occur to me:

Firstly, you are quite likely to be on London clay, so the soil will be heavy and not the best for olives.

Secondly, the soil is buried under decking, so never sees much light and air; ideal conditions for soil borne pathogens.