Establishing Quercus.

We have a 12ft Quercus Suber feathered 20/25cm girth which we bought at that height a year ago.We have a south facing garden.It does not appear to have grown at all since then and now in the last month,the leaves are going yellow with black spots on them and the tree is looking very sick.
Quercus are very hard to establish at the size you have and do not transplant well and can take some time to establish.This is because Quercus team up with a number of other soil organisms including bacteria and fungi.Then transplanting or planting from a pot large Quercus can take time to re-establish these relationships.The only thing I can suggest is to make sure the soil around the tree has a lot of organic matter incorporated into it. For More information.
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