Can Rhizosphaera spread through the soil?

[HeyNow]

Last year at this time I planted 4 Colorado Spruce trees. Within the past 9 months one of them has steadily lost needles from the bottom up. I took a sample in to the local nursery where they looked under a microscope to find fungus. I don’t know for sure but I suspect Rhizosphaera. Shortly after noticing I begin spraying all the trees with chlorothalonil during the growing season. As of last week I conceded the battle and removed the tree. The other trees appear to be unaffected. Despite my best efforts to remove every trace of the diseased tree, countless dead needles and small twigs became mixed with the soil where the old tree was planted. My question is, is it safe to plant a new tree in this location? According to all the articles I’ve read on this, the fungus is transmitted through the needles. Is it also spread underground through the roots? I want to make sure I am not going to have the same results by planting in contaminated soil. If so, is there a way to treat the soil for this?


Any advice would be appreciated.

 

[ATH]

It is not spread through the roots. The spores need to land on a newly forming needle. However, there could still be fungal spores mixed in the soil. You will never get rid of all of them...it is in the air - that is how it got there in the first place. Maintain tree health, good air flow and keep sprinklers off of the tree.