AusBonsai

Whats up everyone.

I just purchased an approximately 40yo English Elm with an awesome hollow and great balance and design. It has spent most of its life in Victoria. 2 years ago it's former owner moved up here and recently put it on the market.

Since its a deciduous tree and my maples and Chinese elms don't really go through the cycles properly I'm wondering if the climate up here isn't very suitable for English Elm and it may not thrive and may tend to keep rotting away?

I don't have many years experience as I only got into bonsai early 2019 and only really took it serious in the last 12 months.

Any advice/information would be greatly appreciated.

Wood rotting away has very little to do with the tree's health or the climate. Conversely, rotting heart wood also has little bearing on the tree's health. Trees can live and stay healthy for many years with a hollow core as all the life processes occur in the sapwood which is the outer layers just under the bark.
Exposed heart wood will always rot. We can slow that process somewhat by using wood preservatives. The best known and traditional bonsai wood preservative is lime sulphur. It is painted onto any exposed wood. It bleaches the wood and kills fungi and bacteria that would otherwise cause rot. Needs to be reapplied every year, sometimes more often.
I have not used any of the modern wood preservative/hardeners but have read that others do use them successfully. Earl's Wood hardener is on brand.

The question of climate is more related to tree health and vitality. I'm not sure how English elms cope with the Qld climate. Chinese elms seem to manage and don't care much about dormancy and cold winters but not sure about English Elm. Your pictures seem to show the tree without leaves so it is either cool enough for it to drop leaves or the tree is dead?

Hoping someone else has more direct experience with EE in QLD for your guidance.