Japan had a government policy of only reforesting with two types of trees for economic purposes, in some cases replacing natural forest, and as a result there's a lack of biodiversity and Japan now has allergy seasons that are estimated to cost $2B a year: https://ensia.com/features/japan-reforestation-deforestation...

To add insult to injury, the economic rationale for planting lots of fast-growing wood never really panned out, because it turned out with even Japanese oversupply of timber that it was cheaper to import it from SEA.