Trees seem to die off
We have a semi bush block in the Mid Blue Mountains, NSW. When we moved in, the entire garden and bush area were overgrown with agapanthus and privet, which I’m making my way through with some pretty good success.
What I’ve noticed is that in the bush area there is a very large concentration of standing dead wood, which was mostly there before we bought the property about five years ago. I know some of the plants, like the giant Acacia in the foreground are furious growers and short lived, but it seems that a lot of the dead trees are Allocasurinas and Eucalyptus.
In the second pic, you can see what I think is a heartwood destroying fungi on a current living tree, so I’ll be saying goodbye to that tree soon I guess.
The block is pretty much a set of sandstone shelves and in a lot of areas the soil is about 20cm deep - there are fissures but it’s quite shallow mostly.
Could it be that the combination of consistent rain and shallow soil just makes all the roots rot? Or is it likely something else? Do privet and agapanthus cause too much competition and starve native trees out?
Any advice would be appreciated, I’d love to make sure my native regeneration is successful.