There is some suspicious data indeed, but the vast majority is correct. The official cadastre of trees is updated every two years by manually visiting each tree.

As for this one tree - maybe there is a decimal point missing in the original data? The tree might have been plantet at an already older age.

Actually I am thinking about updating this data regularly, but never came to that.
The idea is to use the history of the database to identify bogus trees in the original data to not let them be re-imported.